organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoSTRUCTURAL
CHEMISTRY
ISSN: 2053-2296

Conformations of three heterocyclic perhydro­pyrrolobenzo­furans and polymeric assembly via co-operative inter­molecular C—H⋯O hydrogen bonds

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aDepartment of Studies in Chemistry, University of Mysore, Mysore 570 006, India, bFaculty of Health and Life Sciences, Coventry University, Coventry CV1 5FB, England, cD210, Indian Institute of Science, Bangalore 560 012, India, and dOriental Organization of Molecular and Structural Biology, 203 Agarwal Bhavan, Malleshwaram, Bangalore 560 055, India
*Correspondence e-mail: ravindranath_rathore@yahoo.com

(Received 23 March 2006; accepted 28 March 2006; online 13 April 2006)

In 1-cyclo­hexyl-6,6,8a-trimethyl-3a,6,7,8a-tetra­hydro-1H-1-benzofuro[2,3-b]pyrrole-2,4(3H,5H)-dione, C19H27NO3, (I)[link], and the isomorphous compounds 6,6,8a-trimethyl-1-phenyl-3a,6,7,8a-tetra­hydro-1H-1-benzofuro[2,3-b]pyrrole-2,4(3H,5H)-dione, C19H21NO3, (II)[link], and 6,6,8a-trimethyl-1-(3-pyridyl)-3a,6,7,8a-tetra­hydro-1H-1-benzofuro[2,3-b]pyrrole-2,4(3H,5H)-dione, C18H20N2O3, (III)[link], the tetra­hydro­benzo–dihydro­furo–pyrrolidine ring systems are folded at the cis junction of the five-membered rings, giving rise to a non-planar shape of the tricyclic cores. The dihydro­furan and pyrrolidine rings in (I)[link] are puckered and adopt an envelope conformation. The cyclo­hexene rings adopt a half-chair conformation in all the mol­ecules, while the substituent N-cyclo­hexyl ring in (I)[link] assumes a chair form. Short intra­molecular C—H⋯O contacts form S(5) and S(6) motifs. The isomorphous compounds (II)[link] and (III)[link] are effectively isostructural, and aggregate into chains via inter­molecular C—H⋯O hydrogen bonds.

Comment

Co-operativity is an important property of inter­molecular inter­actions and, thereby, mol­ecules assemble into polymers with distinct patterns of inter­actions. By the process of mutual polarization within a polymeric assembly, weaker inter­actions acquire greater strength than they otherwise possess. A dimer of two mol­ecules inter­molecularly connected by symmetrical hydrogen bonds is more stable than if they are connected by an isolated hydrogen bond, the stability of a tetra­mer is greater than that of a pair of dimers, and so on (Desiraju & Steiner, 1999[Desiraju, G. R. & Steiner, T. (1999). The Weak Hydrogen Bond in Structural Chemistry and Biology. New York: Oxford University Press Inc.]; Sharma & Desiraju, 1994[Sharma, C. V. K. & Desiraju, G. R. (1994). J. Chem. Soc. Perkin Trans. 2, pp. 2345-2352.]). Polymeric assemblies formed by co-operative weak inter­actions are the subject of the present discussion. In this report, we present examples of a new class of tricyclic benzofuran derivatives with a benzo­furopyrrolidine ring skeleton. The structural and conformational analyses of three compounds have been undertaken, namely 1-cyclo­hexyl-6,6,8a-trimethyl-3a,6,7,8a-tetra­hydro-1H-1-­benzo­furo[2,3-b]pyrrole-2,4(3H,5H)-dione, (I)[link], 1-phenyl-6,6,8a-trimethyl-3a,6,7,8a-tetra­hydro-1H-1-benzofuro[2,3-b]­pyrrole-2,4(3H,5H)-dione, (II)[link], and 1-pyridin-3-yl-6,6,8a-trimethyl-3a,6,7,8a-tetra­hydro-1H-1-benzofuro[2,3-b]pyrrole-2,4(3H,5H)-dione, (III)[link]. These chiral mol­ecules are formally derived from a perhydro­furo(or -pyrrolo)benzofuran system, and they have previously been shown to exhibit hypoglycaemic activity (Nagarajan et al., 1988[Nagarajan, K., Talwalker, P. K., Nagana Goud, A., Shah, R. K., Shenoy, S. J. & Desai, N. D. (1988). Indian J. Chem. Sect. B, 27, 1113-1123.]).

[Scheme 1]

The stereogenic centres C3a and C8a in compounds (I)[link]–(III)[link] (Figs. 1[link]–3[link][link]) adopt RS and SR configurations, respectively (Cahn et al., 1966[Cahn, R. S., Ingold, C. K. & Prelog, V. (1966). Angew. Chem. Int. Ed. Engl. 5, 385-415.]). The core of each mol­ecule consists of fused tetra­hydro­benzo (A), dihydro­furo (B) and pyrrolidine (C) rings. The C3b=C7a double bond at the AB ring junction is in the range 1.341 (2)–1.344 (2) Å. In each compound, the B and C rings are folded at the BC ring junction, which is cis-fused (Bucourt, 1974[Bucourt, R. (1974). Topics in Stereochemistry, Vol. 8, edited by E. L. Eliel & N. Allinger, pp. 159-224. New York: John Wiley.]). The angles between the best planes through ring B (atoms O8/C8a/C3a/C3b/C7a) and ring C (atoms N1/C2/C3/C3a/C8a) are 66.4 (1), 63.8 (1) and 63.2 (1)°, respectively, while the crossed torsion angles at the junction, i.e. N1—C8a—C3a—C3b and O8—C8a—C3a—C3, are 103.2 (1) and −130.2 (1), 114.3 (1) and −121.2 (1), and 113.4 (1) and −122.3 (1)°, respectively, in the mol­ecules of (I)[link]–(III)[link].

The folding at the BC ring junction gives rise to the non-planarity of the tricyclic ring system. The structures of two analogous mol­ecules based on a chiral tricyclic tetra­hydro­benzo–dihydro­furo–tetra­hydro­furan ­(or pyrrolidine) core, namely 1-isopropyl-6,6,8a-trimethyl-1,3a,5,6,7,8a-hexa­hydro-3H-1-benzofuro[2,3-b]pyrrole-2,4-dione (Narasegowda et al., 2006[Narasegowda, R. S., Yathirajan, H. S., Lynch, D. E., Narasimhamurthy, T. & Rathore, R. S. (2006). Acta Cryst. E62, o1328-o1329.]), (IV), and 6,6,8a-trimethyl-3a,6,7,8a-tetra­hydro-benzo[b]furo[3,2-d]furan-2,4(3H,5H)-dione (Nagaraj et al., 2005[Nagaraj, B., Yathirajan, H. S., Nagaraja, P. & Lynch, D. E. (2005). Acta Cryst. E61, o1041-o1042.]), (V), also possess a similar non-planar shape of the tricyclic core, and the equivalent crossed torsion angles at the junctions of the five-membered rings are 99.7 (1) and −132.8 (1) (values correspond to an inverted image of the reported structure), and 104.0 (1) and −127.2 (1)°, respectively.

The superposition of all five available structures of perhydro­furo(or -pyrrolo)benzofuran derivatives is shown in supplementary Fig. 5. The conformations of the substituent rings, i.e. N-cyclo­hexyl in (I)[link], N-phenyl in (II)[link] and N-pyridyl in (III)[link], are described by torsion angles C8a—N1—C12—C13 of −112.4 (1), −117.2 (2) and −120.2 (1)°, respectively.

The isomorphous compounds (II)[link] and (III)[link], with a difference of one atom [C14 in (II) and N14 in (III)] are isostructural. The degree of isostructurality has been quanti­tatively described by two descriptors, i.e. the unit-cell similarity index, Π, which is the difference between orthogonalized lattice parameters, and the isostructurality index, Ii(n), where n is the number of distance differences between identical non-H atoms (Kálmán et al., 1993[Kálmán, A., Párkányi, L. & Argay, G. (1993). Acta Cryst. B49, 1039-1049.]). The calculated values of Π = 0.019 and Ii(24) = 99.7% indicate the structures are close to the ideal case of isostructrality.

The inter­nal torsion angles of the heterocyclic rings are listed in Figs. 1[link]–3[link][link]. Ring A (cyclo­hexene) adopts a half-chair (C2) conformation in all three mol­ecules. However, its conformation, i.e. a half-chair (C2) versus a sofa (Cs), is hardly distinguishable in the present structures (Bucourt, 1974[Bucourt, R. (1974). Topics in Stereochemistry, Vol. 8, edited by E. L. Eliel & N. Allinger, pp. 159-224. New York: John Wiley.]). The N-cyclo­hexyl ring in (I)[link] assumes a chair form, with the larger tricyclic system in the equatorial position. The puckering (Cremer & Pople, 1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]) and asymmetric (Duax et al., 1976[Duax, W. L., Weeks, C. M. & Rohrer, D. C. (1976). Topics in Stereochemistry, Vol. 9, edited by E. L. Eliel & N. Allinger, pp. 271-383. New York: John Wiley.]) parameters of individual rings are provided in supplementary Table 4. The five-membered B and C rings in (I)[link] are puckered and adopt envelope (Cs) conformations (Fuchs, 1978[Fuchs, B. (1978). Topics in Stereochemistry, Vol. 10, edited by E. L. Eliel & N. Allinger, pp. 1-94. New York: John Wiley.]), with atoms C8a and C3a at the flaps of the envelopes. Atoms C8a and C3a are 0.18 (1) and 0.27 (1) Å, respectively, out of the best planes formed by the other four atoms of the ring. Rings B and C are planar in (II)[link] and (III)[link]. The least-squares planes formed by atoms of rings A and B (C3a/C3b/C4/C5/C7/C7a/O8/C8a) and ring C (N1/C2/O2/C3/C3a/C8a) inter­cept at an angle of 65.8 (1)° in (II)[link] and 64.2 (1)° in (III)[link].

The parameters for intra­molecular short contacts and inter­molecular hydrogen bonds are given in Tables 1[link]–3[link][link]. The conserved intra­molecular C—H⋯O short contacts in (I)–(III) were observed between the donors of the N-substituents and atom O8 of ring B (Figs. 1[link]–3[link][link]). The short contact C12—H12⋯O8 forms an S(5) motif (Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]) in (I)[link], while S(6) motifs are formed by C17—H17⋯O8 in (II)[link] and (III)[link]. Additionally, an intra­molecular C17—H171⋯O2 contact forms an S(6) motif in (I)[link]. The crystal packing in (I)[link] is entirely due to van der Waals inter­actions. The crystal structures of isostructural compounds (II)[link] and (III)[link] are held together primarily by inter­molecular C—H⋯O hydrogen bonds (Tables 2[link] and 3[link]), forming chains of rings along [100] (Fig. 4[link]). The significance of the co-operativity of weak inter­molecular inter­actions for mol­ecular self-assembly is elucidated in the present examples.

[Figure 1]
Figure 1
The mol­ecular structure of (I)[link], showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii. Numerical data refer to the inter­nal torsion angles (°) of the individual rings (s.u. values vary between 0.1 and 0.3°). Intra­molecular C—H⋯O short contacts are shown as dashed lines.
[Figure 2]
Figure 2
The mol­ecular structure of (II)[link], with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii. Numerical data refer to the inter­nal torsion angles (°) of the individual rings (s.u. values vary between 0.1 and 0.3°). The intra­molecular C—H⋯O short contact is shown as a dashed line.
[Figure 3]
Figure 3
The mol­ecular structure of (III)[link], with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii. Numerical data refer to the inter­nal torsion angles (°) of the individual rings (s.u. values vary between 0.1 and 0.3°). The intra­molecular C—H⋯O short contact is shown as a dashed line.
[Figure 4]
Figure 4
The crystal packing, showing the co-operative C—H⋯O hydrogen-bonded polymeric association of isostructural compounds (II)[link] and (III)[link], viewed along the a axis. The representative diagram corresponds to the packing in (II)[link]. Atoms labelled with an asterisk (*) or a hash (#) are at the symmetry positions (−x + 1, −y + 1, −z + 1) and (x + 1, y, z), respectively. Inter­molecular C—H⋯O hydrogen bonds are shown as dashed lines.

Experimental

The synthetic procedures used for the preparation of compounds (I)[link]–(III)[link] are as described in the literature (Nagarajan et al., 1988[Nagarajan, K., Talwalker, P. K., Nagana Goud, A., Shah, R. K., Shenoy, S. J. & Desai, N. D. (1988). Indian J. Chem. Sect. B, 27, 1113-1123.]). Single crystals suitable for X-ray diffraction were grown by slow evaporation of solutions containing the following solvents (in a 1:1 ratio): for (I)[link], ethanol and water; for (II)[link], dichloro­methane and hexane; for (III)[link], benzene and hexane.

Compound (I)[link]

Crystal data
  • C19H27NO3

  • Mr = 317.42

  • Triclinic, [P \overline 1]

  • a = 9.4708 (2) Å

  • b = 10.2139 (2) Å

  • c = 10.7512 (2) Å

  • α = 105.804 (1)°

  • β = 99.141 (1)°

  • γ = 116.320 (1)°

  • V = 848.50 (3) Å3

  • Z = 2

  • Dx = 1.242 Mg m−3

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 120 (2) K

  • Plate, colourless

  • 0.24 × 0.16 × 0.03 mm

Data collection
  • Nonius KappaCCD area-detector diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.891, Tmax = 0.998

  • 18064 measured reflections

  • 3327 independent reflections

  • 2990 reflections with I > 2σ(I)

  • Rint = 0.039

  • θmax = 26.0°

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.107

  • S = 1.12

  • 3327 reflections

  • 316 parameters

  • All H-atom parameters refined

  • w = 1/[σ2(Fo2) + (0.0495P)2 + 0.3127P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max = 0.001

  • Δρmax = 0.30 e Å−3

  • Δρmin = −0.32 e Å−3

Table 1
Hydrogen-bond and short-contact geometry (Å, °) for (I)[link]

D—H⋯A D—H H⋯A DA D—H⋯A
C12—H12⋯O8 1.00 (2) 2.52 (2) 2.920 (2) 103 (1)
C17—H171⋯O2 1.01 (2) 2.55 (2) 3.153 (2) 118 (1)

Compound (II)[link]

Crystal data
  • C19H21NO3

  • Mr = 311.37

  • Triclinic, [P \overline 1]

  • a = 7.2348 (2) Å

  • b = 10.1212 (5) Å

  • c = 11.6287 (6) Å

  • α = 77.031 (2)°

  • β = 79.285 (3)°

  • γ = 76.872 (3)°

  • V = 799.89 (6) Å3

  • Z = 2

  • Dx = 1.293 Mg m−3

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 120 (2) K

  • Plate, colourless

  • 0.20 × 0.14 × 0.03 mm

Data collection
  • Nonius KappaCCD area-detector diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.903, Tmax = 0.997

  • 14845 measured reflections

  • 3132 independent reflections

  • 2562 reflections with I > 2σ(I)

  • Rint = 0.047

  • θmax = 26.0°

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.117

  • S = 1.07

  • 3132 reflections

  • 292 parameters

  • All H-atom parameters refined

  • w = 1/[σ2(Fo2) + (0.0532P)2 + 0.358P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max = 0.001

  • Δρmax = 0.19 e Å−3

  • Δρmin = −0.27 e Å−3

Table 2
Hydrogen-bond and short-contact geometry (Å, °) for (II)[link]

D—H⋯A D—H H⋯A DA D—H⋯A
C17—H17⋯O8 1.00 (2) 2.49 (2) 3.066 (2) 116 (2)
C7—H72⋯O2i 0.96 (2) 2.49 (2) 3.275 (2) 140 (2)
C16—H16⋯O2ii 0.98 (2) 2.46 (2) 3.243 (3) 138 (2)
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) x+1, y, z.

Compound (III)[link]

Crystal data
  • C18H20N2O3

  • Mr = 312.36

  • Triclinic, [P \overline 1]

  • a = 7.2330 (2) Å

  • b = 9.8165 (3) Å

  • c = 11.6008 (3) Å

  • α = 78.541 (2)°

  • β = 78.992 (2)°

  • γ = 77.302 (1)°

  • V = 778.13 (4) Å3

  • Z = 2

  • Dx = 1.333 Mg m−3

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 120 (2) K

  • Prism, colourless

  • 0.19 × 0.14 × 0.09 mm

Data collection
  • Nonius KappaCCD area-detector diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.913, Tmax = 0.992

  • 13914 measured reflections

  • 3040 independent reflections

  • 2769 reflections with I > 2σ(I)

  • Rint = 0.035

  • θmax = 26.0°

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.104

  • S = 1.07

  • 3040 reflections

  • 288 parameters

  • All H-atom parameters refined

  • w = 1/[σ2(Fo2) + (0.0478P)2 + 0.3717P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max = 0.006

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.20 e Å−3

Table 3
Hydrogen-bond and short-contact geometry (Å, °) for (III)[link]

D—H⋯A D—H H⋯A DA D—H⋯A
C17—H17⋯O8 0.99 (2) 2.50 (2) 3.060 (2) 116 (2)
C7—H72⋯O2i 0.99 (2) 2.49 (2) 3.295 (2) 138 (1)
C16—H16⋯O2ii 0.97 (2) 2.54 (2) 3.268 (2) 132 (2)
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) x+1, y, z.

Larger-than-expected values of residual electron density were observed in (I)[link] and (III)[link] [the values of Δρmax and Δρmin were 0.75 and −0.88 e Å−3, respectively, in (I)[link], and 0.82 and −0.87 e Å−3, respectively, in (III)]. This was attributed to the presence of a few poorly fitting low-angle reflections [(011), ([\overline{1}][\overline{1}]1), (020), (111) and ([\overline{2}][\overline{1}]2) in (I)[link], and (1[\overline{1}]2), (100), ([\overline{1}]11), (022), (013), (122) and (012) in (III)], which appeared to have been truncated by the beam stop. These reflections were omitted during the final cycles of refinement. The residual electron density was then featureless and the residual factor R dropped from 0.053 to 0.039 in (I)[link], and from 0.056 to 0.039 in (III)[link] for observed data.

H atoms were located in difference maps and were refined freely. Refined methine, methylene and methyl C—H distances are as follows: for (I)[link], 0.99 (2), 0.97 (2)–1.01 (2) and 0.96 (2)–1.02 (2) Å; for (II)[link], 0.97 (2), 0.96 (2)–1.01 (2) and 0.97 (2)–1.03 (2) Å, with aromatic C—H = 0.96 (2)–1.00 (2) Å; for (III)[link], 0.99 (2), 0.97 (2)–1.02 (2) and 0.98 (2)–1.02 (2) Å, with aromatic C—H = 0.97 (2)–1.01 (2) Å.

For all compounds, data collection: COLLECT (Nonius, 1998[Nonius (1998). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]), PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]) and INSIGHTII (Accelrys, 2002[Accelrys (2002). INSIGHTII. Version 2000.2. Accelrys Inc., 9685 Scranton Road, San Diego, CA 92121-3752, USA.]); software used to prepare material for publication: SHELXL97 and PLATON.

Supporting information


Comment top

Co-operativity is an important property of intermolecular interactions, and thereby molecules assemble into polymers with distinct patterns of interactions. By the process of mutual polarization within a polymeric assembly, weaker interactions acquire greater strength than they otherwise possess. A dimer of two molecules intermolecularly connected by symmetrical hydrogen bonds is more stable than if they are connected by an isolated hydrogen bond, the stability of a tetramer is greater than that of a pair of dimers, and so on (Desiraju & Steiner, 1999; Sharma & Desiraju, 1994). Polymeric assemblies formed by cooperative weak interactions are the subject of the present discussion. In this report, we present examples of a new class of tricyclic benzofuran derivatives with a benzofuropyrrolidine ring skeleton. The structural and conformational analyses of three compounds have been undertaken: 1-cyclohexyl-6,6,8a-trimethyl-3a,6,7,8a-tetrahydro-1H-[1]benzofuro[2,3-b]pyrrole-2,4(3H,5H)-dione, (I), 1-phenyl-6,6,8a-trimethyl-3a,6,7,8a-tetrahydro-1H-[1]benzofuro[2,3-b]pyrrole-2,4(3H,5H)-dione, (II), and 1-pyridin-3-yl-6,6,8a-trimethyl-3a,6,7,8a-tetrahydro-1H-[1]benzofuro[2,3-b]pyrrole-2,4(3H,5H)-dione, (III). These chiral molecules are formally derived from a perhydrofuro(or -pyrrolo)benzofuran system, and they have previously been shown to exhibit hypoglycaemic activity (Nagarajan et al., 1988).

The stereogenic centres C3a and C8a in compounds (I)–(III) (Figs. 1–3) adopt RS and SR configurations, respectively (Cahn et al., 1966). The core of each molecule consists of fused tetrahydrobenzo (A), dihydrofuro (B) and pyrrolidine (C) rings. The C3bC7a double bond at the AB ring junction is in the range 1.341 (2)–1.344 (2) Å. In each compound, the B and C rings are folded at the BC ring junction, which is cis-fused (Bucourt, 1974). The angles between the best planes through ring B (atoms O8/C8a/C3a/C3b/C7a) and ring C (atoms N1/C2/C3/C3a/C8a) are 66.4 (1), 63.8 (1) and 63.2 (1)°, respectively, while the crossed torsion angles at the junction, i.e. N1—C8a—C3a—C3b and O8—C8a—C3a—C3, are 103.2 (1) and −130.2 (1)°, 114.3 (1) and −121.2 (1)°, and 113.4 (1) and −122.3 (1)°, respectively, in the molecules of (I)–(III).

The folding at the BC ring junction gives rise to the non-planarity of the tricyclic ring system. The structures of two analogous molecules based on a chiral tricyclic tetrahydrobenzo–dihydrofuro–tetrahydrofuran(or pyrrolidine) core, namely 1-isopropyl-6,6,8a-trimethyl-1,3a,5,6,7,8a-hexahydro-3H-1-benzofuro[2,3-b]pyrrole-2,4-dione (Narasegowda et al., 2006), (IV), and 6,6,8a-trimethyl-3a,6,7,8a-tetrahydro-benzo[b]furo[3,2-d]furan-2,4(3H,5H)-dione (Nagaraj et al., 2005), (V), also possess a similar non-planar shape of the tricyclic core, and the equivalent crossed torsion angles at the junctions of the five-membered rings are 99.7 (1) and −132.8 (1)° (values correspond to an inverted image of the reported structure) and 104.0 (1) and −127.2 (1)°, respectively.

The superposition of all five available structures of perhydrofuro- (or -pyrrolo)benzofuran derivatives is shown in supplementary Fig. 5. The conformations of the substituent rings, i.e. N-cyclohexyl in (I), N-phenyl in (II) and N-pyridyl in (III), are described by torsion angles C8a—N1—C12—C13 = −112.4 (1), −117.2 (2) and −120.2 (1)°, respectively.

The isomorphous compounds (II) and (III), with a difference of one atom [C14 in (II)/N14 in (III)] are isostructural. The degree of isostructurality has been quantitatively described by two descriptors, i.e. the unit-cell similarity index, Π, which is the difference between orthogonalized lattice parameters, and the isostructurality index, Ii(n), where n is the number of distance differences between identical non-H atoms (Kálmán et al., 1993). The calculated values of Π = 0.019 and Ii(24) = 99.7% indicate the structures are close to the ideal case of isostructrality.

The internal torsion angles of the heterocyclic rings are listed in Figs. 1–3. Ring A (cyclohexene) adopts a half-chair (C2) conformation in all three molecules. However, its conformation, i.e. a half-chair (C2) versus a sofa (Cs), is hardly distinguishable in the present structures (Bucourt, 1974). The N-cyclohexyl ring in (I) assumes a chair form, with the larger tricyclic system in the equatorial position. The puckering (Cremer & Pople, 1975) and asymmetric (Duax et al., 1976) parameters of individual rings are provided in supplementary Table 4. The five-membered B and C rings in (I) are puckered and adopt envelope (Cs) conformations (Fuchs, 1978), with atoms C8a and C3a at the flaps of the envelopes. Atoms C8a and C3a are 0.18 (1) and 0.27 (1) Å, respectively, out of the best planes formed by the other four atoms of the ring. Rings B and C are planar in (II) and (III). The least square planes formed by atoms of rings A and B (C3a/C3b/C4/C5/C7/C7a/O8/C8a) and ring C (N1/C2/O2/C3/C3a/C8a) intercept at an angle of 65.8 (1)° in (II) and 64.2 (1)° in (III).

The parameters for intramolecular short contacts and intermolecular hydrogen bonds are given in Tables 1–3. The conserved intramolecular C—H···O short contacts in (I)–(III) were observed between the donors of the N-substituents and atom O8 of ring B (Figs. 1–3). The short contact C12—H12···O8 forms an S(5) motif (Bernstein et al., 1995) in (I), while S(6) motifs are formed by C17—H17···O8 in (II) and (III). Additionally, an intramolecular C17—H171···O2 contact forms an S(6) motif in (I). The crystal packing in (I) is entirely due to van der Waals interactions. The crystal structures of isostructural compounds (II) and (III) are held together primarily by intermolecular C—H···O hydrogen bonds (Tables 2 and 3), forming chains of rings along [100] (Fig. 4). The significance of the cooperativity of weak intermolecular interactions for molecular self-assembly is elucidated in the present examples.

Experimental top

The synthetic procedures for compounds (I)–(III) are as described in the literature (Nagarajan et al., 1988). Suitable single crystals for X-ray diffraction were grown by slow evaporation of solutions containing the following solvents (in 1:1 ratio): for (I), ethyl alcohol and water; for (II), dichloromethane and hexane; for (III), benzene and hexane.

Refinement top

Larger than expected values of residual electron density were observed in (I) and (III) [the values of Δρmax and Δρmin were 0.75 and −0.88 e Å−3, respectively, in (I), and 0.82 and −0.87 e Å−3, respectively, in (III)]. This was attributed to the presence of a few poorly fitting low-angle reflections [(011), (111), (020), (111) and (212) in (I), and (112), (100), (111), (022), (013), (122) and (012) in (III)], which appeared to have been truncated by the beam stop. These reflections were omitted during the final cycles of refinement. The residual electron density was then featureless and the residual factor R dropped from 0.053 to 0.039 in (I), and from 0.056 to 0.039 in (III) for observed data.

H atoms were located in difference maps and were refined freely. Refined C—H distances are in the following ranges. For (I): Cmethine—H = 0.99 (2), Cmethylene—H = 0.97 (2)–1.01 (2) and Cmethyl—H = 0.96 (2)–1.02 (2) Å. For (II): Cmethine—H = 0.97 (2), Cmethylene—H = 0.96 (2)–1.01 (2), Cmethyl—H = 0.97 (2)–1.03 (2) and Car—H = 0.96 (2)–1.00 (2) Å. For (III): Cmethine—H = 0.99 (2), Cmethylene—H = 0.97 (2)–1.02 (2), Cmethyl—H = 0.98 (2)–1.02 (2) and Car—H = 0.97 (2)–1.01 (2) Å.

Computing details top

For all compounds, data collection: COLLECT (Nonius, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Farrugia, 1997), PLATON (Spek, 2003) and INSIGHTII (Accelrys, 2002); software used to prepare material for publication: SHELXL97 and PLATON).

Figures top
[Figure 1]
[Figure 2]
[Figure 3]
[Figure 4]
Fig. 1. The molecular structure of (I), with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii. Numerical data refer to the internal torsion angles (°) of the individual rings (s.u.s vary between 0.1 and 0.3°). Intramolecular C—H···O short contacts are shown as dashed lines.

Fig. 2. The molecular structure of (II), with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii. Numerical data refer to the internal torsion angles (°) of the individual rings (s.u.s vary between 0.1 and 0.3°). The intramolecular C—H···O short contact is shown as a dashed line.

Fig. 3. The molecular structure of (III), with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii. Numerical data refer to the internal torsion angles (°) of the individual rings (s.u.s vary between 0.1 and 0.3°). The intramolecular C—H···O short contact is shown as a dashed line.

Fig. 4. The crystal packing, showing the cooperative C—H···O hydrogen-bonded polymeric association of the isostructural compounds (II) and (III), viewed along the a axis. The representative diagram corresponds to the packing in (II). Atoms labelled with an asterisk (*) or a hash (#) are at the symmetry positions (−x + 1, −y + 1, −z + 1) and (x + 1, y, z), respectively. Intermolecular C—H···O hydrogen bonds are shown as dashed lines.

Fig. 5. (Supplementary material). A superposition diagram of all five structures of the tricyclic compounds (I)–(V), which are derived from a perhydrofuro (or -pyrrolo)benzofuran system. The r.m.s. deviations are in the range 0.05–0.26 Å, with respect to (II). Colour scheme: (I) blue, (II) green, (III) cyan, (IV) magenta and (V) orange.
(I) 1-cyclohexyl-6,6,8a-trimethyl-3a,6,7,8a-tetrahydro- 1H-[1]benzofuro[2,3-b]pyrrole-2,4(3H,5H)-dione top
Crystal data top
C19H27NO3Z = 2
Mr = 317.42F(000) = 344
Triclinic, P1Dx = 1.242 Mg m3
Hall symbol: -P 1Melting point: 164(1) K
a = 9.4708 (2) ÅMo Kα radiation, λ = 0.71073 Å
b = 10.2139 (2) ÅCell parameters from 3830 reflections
c = 10.7512 (2) Åθ = 2.9–27.5°
α = 105.804 (1)°µ = 0.08 mm1
β = 99.141 (1)°T = 120 K
γ = 116.320 (1)°Plate, colourless
V = 848.50 (3) Å30.24 × 0.16 × 0.03 mm
Data collection top
Nonius KappaCCD area-detector
diffractometer
3327 independent reflections
Radiation source: Bruker Nonius FR591 rotating anode2990 reflections with I > 2σ(I)
10 cm confocal mirrors monochromatorRint = 0.039
Detector resolution: 9.091 pixels mm-1θmax = 26.0°, θmin = 3.1°
ϕ and ω scansh = 1111
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
k = 1212
Tmin = 0.891, Tmax = 0.998l = 1313
18064 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.039Hydrogen site location: difference Fourier map
wR(F2) = 0.107All H-atom parameters refined
S = 1.12 w = 1/[σ2(Fo2) + (0.0495P)2 + 0.3127P]
where P = (Fo2 + 2Fc2)/3
3327 reflections(Δ/σ)max = 0.001
316 parametersΔρmax = 0.30 e Å3
0 restraintsΔρmin = 0.32 e Å3
Crystal data top
C19H27NO3γ = 116.320 (1)°
Mr = 317.42V = 848.50 (3) Å3
Triclinic, P1Z = 2
a = 9.4708 (2) ÅMo Kα radiation
b = 10.2139 (2) ŵ = 0.08 mm1
c = 10.7512 (2) ÅT = 120 K
α = 105.804 (1)°0.24 × 0.16 × 0.03 mm
β = 99.141 (1)°
Data collection top
Nonius KappaCCD area-detector
diffractometer
3327 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
2990 reflections with I > 2σ(I)
Tmin = 0.891, Tmax = 0.998Rint = 0.039
18064 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.107All H-atom parameters refined
S = 1.12Δρmax = 0.30 e Å3
3327 reflectionsΔρmin = 0.32 e Å3
316 parameters
Special details top

Experimental. The minimum and maximum absorption values stated above are those calculated in SHELXL97 from the given crystal dimensions. The ratio of minimum to maximum apparent transmission was determined experimentally as 0.872591.

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.66945 (13)0.83321 (13)0.06540 (11)0.0167 (2)
C20.54206 (16)0.76998 (16)0.11506 (14)0.0195 (3)
O20.39388 (12)0.69213 (12)0.04877 (10)0.0268 (2)
C30.61545 (17)0.81694 (17)0.26714 (14)0.0205 (3)
H310.566 (2)0.723 (2)0.2919 (17)0.028 (4)*
H320.586 (2)0.892 (2)0.3135 (16)0.025 (4)*
C3a0.80351 (16)0.89310 (15)0.29567 (13)0.0177 (3)
H3A0.8681 (19)0.9908 (18)0.3799 (16)0.019 (4)*
C3b0.86820 (15)0.78212 (15)0.29228 (13)0.0175 (3)
C40.86882 (15)0.69968 (16)0.38229 (13)0.0195 (3)
O40.82106 (12)0.71866 (12)0.48206 (10)0.0260 (2)
C50.93232 (17)0.58661 (17)0.34377 (15)0.0232 (3)
H510.836 (2)0.483 (2)0.2755 (19)0.035 (5)*
H520.965 (2)0.564 (2)0.4265 (18)0.029 (4)*
C61.07746 (16)0.64508 (16)0.28581 (14)0.0202 (3)
C71.02171 (17)0.67990 (16)0.16153 (14)0.0198 (3)
H711.119 (2)0.7370 (19)0.1328 (16)0.024 (4)*
H720.939 (2)0.580 (2)0.0830 (18)0.030 (4)*
C7a0.94005 (15)0.77378 (15)0.19475 (13)0.0167 (3)
O80.93695 (11)0.86367 (11)0.12332 (9)0.0180 (2)
C8a0.83307 (15)0.92847 (15)0.16778 (13)0.0167 (3)
C91.1212 (2)0.51662 (18)0.23972 (17)0.0287 (3)
H911.212 (2)0.550 (2)0.1979 (18)0.034 (5)*
H921.022 (2)0.418 (2)0.1693 (18)0.033 (4)*
H931.161 (2)0.492 (2)0.320 (2)0.040 (5)*
C101.22956 (17)0.79503 (18)0.39645 (15)0.0244 (3)
H1011.261 (2)0.776 (2)0.4802 (19)0.038 (5)*
H1021.211 (2)0.889 (2)0.4228 (18)0.033 (4)*
H1031.328 (2)0.828 (2)0.3632 (18)0.037 (5)*
C110.92108 (18)1.10020 (16)0.18603 (15)0.0219 (3)
H1110.939 (2)1.112 (2)0.1012 (19)0.032 (4)*
H1121.028 (2)1.158 (2)0.2568 (18)0.030 (4)*
H1130.851 (2)1.142 (2)0.2104 (18)0.034 (5)*
C120.65163 (16)0.81188 (15)0.07822 (13)0.0170 (3)
H120.7669 (19)0.8633 (17)0.0830 (15)0.016 (3)*
C130.56535 (18)0.89201 (17)0.12881 (14)0.0216 (3)
H1310.449 (2)0.8404 (19)0.1287 (16)0.024 (4)*
H1320.622 (2)1.005 (2)0.0663 (17)0.027 (4)*
C140.56686 (18)0.87682 (16)0.27380 (14)0.0231 (3)
H1410.685 (2)0.935 (2)0.2711 (17)0.027 (4)*
H1420.512 (2)0.931 (2)0.3057 (17)0.029 (4)*
C150.48386 (18)0.70394 (16)0.37073 (14)0.0217 (3)
H1510.362 (2)0.648 (2)0.3810 (17)0.027 (4)*
H1520.491 (2)0.6975 (19)0.4646 (17)0.024 (4)*
C160.56366 (18)0.62014 (16)0.31776 (13)0.0209 (3)
H1610.679 (2)0.6661 (19)0.3198 (16)0.025 (4)*
H1620.503 (2)0.507 (2)0.3774 (18)0.029 (4)*
C170.56744 (17)0.63732 (15)0.17124 (13)0.0192 (3)
H1710.451 (2)0.5785 (19)0.1672 (16)0.024 (4)*
H1720.629 (2)0.5888 (19)0.1361 (17)0.025 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0141 (5)0.0185 (5)0.0162 (5)0.0077 (4)0.0039 (4)0.0066 (4)
C20.0184 (7)0.0206 (6)0.0231 (7)0.0117 (6)0.0083 (5)0.0093 (5)
O20.0157 (5)0.0338 (6)0.0274 (5)0.0099 (4)0.0063 (4)0.0124 (4)
C30.0202 (7)0.0259 (7)0.0212 (7)0.0148 (6)0.0098 (5)0.0105 (6)
C3a0.0181 (6)0.0190 (6)0.0161 (6)0.0099 (5)0.0057 (5)0.0061 (5)
C3b0.0151 (6)0.0201 (6)0.0162 (6)0.0090 (5)0.0037 (5)0.0063 (5)
C40.0125 (6)0.0234 (7)0.0185 (6)0.0059 (5)0.0031 (5)0.0092 (5)
O40.0245 (5)0.0353 (6)0.0200 (5)0.0138 (5)0.0100 (4)0.0143 (4)
C50.0201 (7)0.0259 (7)0.0287 (7)0.0118 (6)0.0087 (6)0.0170 (6)
C60.0182 (7)0.0225 (7)0.0243 (7)0.0118 (6)0.0073 (5)0.0124 (6)
C70.0195 (7)0.0230 (7)0.0210 (7)0.0129 (6)0.0084 (5)0.0097 (6)
C7a0.0142 (6)0.0176 (6)0.0160 (6)0.0069 (5)0.0024 (5)0.0071 (5)
O80.0182 (5)0.0236 (5)0.0189 (4)0.0137 (4)0.0082 (4)0.0111 (4)
C8a0.0148 (6)0.0188 (6)0.0171 (6)0.0097 (5)0.0051 (5)0.0060 (5)
C90.0310 (8)0.0279 (8)0.0387 (9)0.0204 (7)0.0147 (7)0.0177 (7)
C100.0176 (7)0.0286 (8)0.0275 (7)0.0121 (6)0.0045 (6)0.0128 (6)
C110.0199 (7)0.0186 (7)0.0235 (7)0.0081 (6)0.0045 (6)0.0076 (6)
C120.0158 (6)0.0189 (6)0.0163 (6)0.0088 (5)0.0049 (5)0.0069 (5)
C130.0256 (7)0.0210 (7)0.0216 (7)0.0150 (6)0.0068 (6)0.0079 (6)
C140.0269 (8)0.0226 (7)0.0229 (7)0.0145 (6)0.0061 (6)0.0111 (6)
C150.0218 (7)0.0238 (7)0.0184 (7)0.0110 (6)0.0050 (5)0.0084 (5)
C160.0227 (7)0.0197 (7)0.0188 (6)0.0113 (6)0.0060 (5)0.0052 (5)
C170.0208 (7)0.0182 (6)0.0191 (6)0.0109 (6)0.0050 (5)0.0072 (5)
Geometric parameters (Å, º) top
N1—C21.3635 (17)C9—H911.006 (19)
N1—C8a1.4482 (16)C9—H920.994 (19)
N1—C121.4702 (16)C9—H931.02 (2)
C2—O21.2222 (17)C10—H1010.999 (19)
C2—C31.5175 (19)C10—H1021.022 (18)
C3—C3a1.5295 (18)C10—H1031.003 (19)
C3—H310.994 (18)C11—H1110.982 (18)
C3—H320.971 (17)C11—H1120.965 (18)
C3a—C3b1.5040 (17)C11—H1130.968 (19)
C3a—C8a1.5500 (17)C12—C131.5256 (18)
C3a—H3A0.990 (16)C12—C171.5263 (18)
C3b—C7a1.3414 (18)C12—H120.998 (15)
C3b—C41.4463 (18)C13—C141.5270 (19)
C4—O41.2294 (16)C13—H1310.990 (17)
C4—C51.5171 (19)C13—H1320.991 (17)
C5—C61.5432 (18)C14—C151.5260 (19)
C5—H510.997 (19)C14—H1410.998 (18)
C5—H521.013 (17)C14—H1420.998 (18)
C6—C91.5267 (19)C15—C161.5266 (19)
C6—C101.5305 (19)C15—H1511.002 (17)
C6—C71.5465 (18)C15—H1521.009 (17)
C7—C7a1.4845 (18)C16—C171.5296 (18)
C7—H710.995 (17)C16—H1610.983 (17)
C7—H720.991 (18)C16—H1620.982 (18)
C7a—O81.3544 (15)C17—H1711.011 (17)
O8—C8a1.4795 (15)C17—H1721.010 (17)
C8a—C111.5080 (18)
C2—N1—C8a114.36 (10)C6—C9—H92109.9 (10)
C2—N1—C12125.58 (11)H91—C9—H92107.6 (14)
C8a—N1—C12120.06 (10)C6—C9—H93111.2 (10)
O2—C2—N1125.67 (12)H91—C9—H93107.9 (15)
O2—C2—C3125.93 (12)H92—C9—H93109.1 (15)
N1—C2—C3108.38 (11)C6—C10—H101111.0 (11)
C2—C3—C3a105.27 (10)C6—C10—H102112.4 (10)
C2—C3—H31110.5 (10)H101—C10—H102108.9 (14)
C3a—C3—H31113.6 (10)C6—C10—H103110.3 (10)
C2—C3—H32106.7 (10)H101—C10—H103107.0 (15)
C3a—C3—H32112.0 (10)H102—C10—H103107.1 (14)
H31—C3—H32108.6 (14)C8a—C11—H111111.6 (10)
C3b—C3a—C3114.80 (11)C8a—C11—H112109.7 (10)
C3b—C3a—C8a100.65 (10)H111—C11—H112108.8 (14)
C3—C3a—C8a104.98 (10)C8a—C11—H113107.6 (11)
C3b—C3a—H3A111.6 (9)H111—C11—H113108.2 (15)
C3—C3a—H3A112.6 (9)H112—C11—H113110.8 (15)
C8a—C3a—H3A111.3 (9)N1—C12—C13113.06 (10)
C7a—C3b—C4121.24 (12)N1—C12—C17111.57 (10)
C7a—C3b—C3a110.25 (11)C13—C12—C17111.68 (11)
C4—C3b—C3a128.39 (11)N1—C12—H12106.2 (8)
O4—C4—C3b122.91 (12)C13—C12—H12107.8 (8)
O4—C4—C5122.29 (12)C17—C12—H12106.0 (8)
C3b—C4—C5114.80 (11)C12—C13—C14109.33 (11)
C4—C5—C6114.23 (11)C12—C13—H131109.5 (10)
C4—C5—H51107.3 (11)C14—C13—H131109.5 (9)
C6—C5—H51110.1 (10)C12—C13—H132110.1 (10)
C4—C5—H52108.7 (10)C14—C13—H132110.9 (10)
C6—C5—H52110.6 (9)H131—C13—H132107.4 (13)
H51—C5—H52105.4 (14)C15—C14—C13111.61 (11)
C9—C6—C10109.47 (11)C15—C14—H141109.3 (10)
C9—C6—C5109.62 (11)C13—C14—H141108.5 (10)
C10—C6—C5109.49 (11)C15—C14—H142111.6 (10)
C9—C6—C7109.26 (11)C13—C14—H142108.9 (10)
C10—C6—C7110.43 (11)H141—C14—H142106.9 (14)
C5—C6—C7108.56 (11)C14—C15—C16111.25 (11)
C7a—C7—C6110.36 (11)C14—C15—H151109.5 (9)
C7a—C7—H71110.5 (9)C16—C15—H151109.4 (10)
C6—C7—H71110.5 (9)C14—C15—H152110.0 (9)
C7a—C7—H72107.3 (10)C16—C15—H152110.1 (9)
C6—C7—H72110.3 (10)H151—C15—H152106.6 (13)
H71—C7—H72107.9 (13)C15—C16—C17112.04 (11)
C3b—C7a—O8114.43 (11)C15—C16—H161109.1 (10)
C3b—C7a—C7126.56 (12)C17—C16—H161108.6 (10)
O8—C7a—C7119.00 (11)C15—C16—H162110.2 (10)
C7a—O8—C8a106.82 (9)C17—C16—H162109.3 (10)
N1—C8a—O8107.81 (9)H161—C16—H162107.5 (14)
N1—C8a—C11113.69 (11)C12—C17—C16110.26 (11)
O8—C8a—C11107.18 (10)C12—C17—H171109.3 (9)
N1—C8a—C3a104.22 (10)C16—C17—H171110.9 (9)
O8—C8a—C3a106.56 (10)C12—C17—H172109.5 (9)
C11—C8a—C3a116.88 (11)C16—C17—H172110.3 (9)
C6—C9—H91111.0 (10)H171—C17—H172106.4 (13)
C8a—N1—C2—O2176.43 (13)C3b—C7a—O8—C8a6.95 (14)
C12—N1—C2—O23.5 (2)C7—C7a—O8—C8a173.97 (11)
C8a—N1—C2—C31.88 (14)C2—N1—C8a—O8124.67 (11)
C12—N1—C2—C3178.23 (11)C12—N1—C8a—O855.44 (14)
O2—C2—C3—C3a172.73 (13)C2—N1—C8a—C11116.66 (12)
N1—C2—C3—C3a8.97 (14)C12—N1—C8a—C1163.23 (15)
C2—C3—C3a—C3b94.13 (13)C2—N1—C8a—C3a11.71 (14)
C2—C3—C3a—C8a15.40 (13)C12—N1—C8a—C3a168.40 (10)
C3—C3a—C3b—C7a119.17 (12)C7a—O8—C8a—N1100.30 (11)
C8a—C3a—C3b—C7a7.05 (13)C7a—O8—C8a—C11136.94 (11)
C3—C3a—C3b—C464.82 (17)C7a—O8—C8a—C3a11.09 (12)
C8a—C3a—C3b—C4176.94 (12)C3b—C3a—C8a—N1103.18 (11)
C7a—C3b—C4—O4171.61 (13)C3—C3a—C8a—N116.30 (13)
C3a—C3b—C4—O44.0 (2)C3b—C3a—C8a—O810.68 (12)
C7a—C3b—C4—C58.72 (18)C3—C3a—C8a—O8130.16 (10)
C3a—C3b—C4—C5175.66 (12)C3b—C3a—C8a—C11130.43 (11)
O4—C4—C5—C6143.62 (13)C3—C3a—C8a—C11110.10 (13)
C3b—C4—C5—C636.71 (16)C2—N1—C12—C1367.52 (16)
C4—C5—C6—C9175.28 (12)C8a—N1—C12—C13112.36 (13)
C4—C5—C6—C1064.61 (15)C2—N1—C12—C1759.36 (16)
C4—C5—C6—C756.01 (15)C8a—N1—C12—C17120.76 (12)
C9—C6—C7—C7a166.22 (11)N1—C12—C13—C14174.79 (11)
C10—C6—C7—C7a73.33 (14)C17—C12—C13—C1458.39 (15)
C5—C6—C7—C7a46.71 (15)C12—C13—C14—C1557.18 (15)
C4—C3b—C7a—O8176.75 (11)C13—C14—C15—C1655.25 (16)
C3a—C3b—C7a—O80.41 (16)C14—C15—C16—C1753.56 (16)
C4—C3b—C7a—C72.3 (2)N1—C12—C17—C16175.37 (10)
C3a—C3b—C7a—C7178.59 (12)C13—C12—C17—C1657.00 (14)
C6—C7—C7a—C3b22.69 (18)C15—C16—C17—C1254.13 (15)
C6—C7—C7a—O8156.26 (11)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C12—H12···O81.00 (2)2.52 (2)2.920 (2)103 (1)
C17—H171···O21.01 (2)2.55 (2)3.153 (2)118 (1)
(II) 6,6,8a-trimethyl-1-phenyl-3a,6,7,8a-tetrahydro- 1H-[1]benzofuro[2,3-b]pyrrole-2,4(3H,5H)-dione top
Crystal data top
C19H21NO3Z = 2
Mr = 311.37F(000) = 332
Triclinic, P1Dx = 1.293 Mg m3
Hall symbol: -P 1Melting point: 140(2) K
a = 7.2348 (2) ÅMo Kα radiation, λ = 0.71073 Å
b = 10.1212 (5) ÅCell parameters from 3590 reflections
c = 11.6287 (6) Åθ = 2.9–27.5°
α = 77.031 (2)°µ = 0.09 mm1
β = 79.285 (3)°T = 120 K
γ = 76.872 (3)°Plate, colourless
V = 799.89 (6) Å30.20 × 0.14 × 0.03 mm
Data collection top
Nonius KappaCCD area-detector
diffractometer
3132 independent reflections
Radiation source: Bruker Nonius FR591 rotating anode2562 reflections with I > 2σ(I)
10 cm confocal mirrors monochromatorRint = 0.047
Detector resolution: 9.091 pixels mm-1θmax = 26.0°, θmin = 2.9°
ϕ and ω scansh = 88
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
k = 1212
Tmin = 0.903, Tmax = 0.997l = 1414
14845 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.044Hydrogen site location: difference Fourier map
wR(F2) = 0.117All H-atom parameters refined
S = 1.07 w = 1/[σ2(Fo2) + (0.0532P)2 + 0.358P]
where P = (Fo2 + 2Fc2)/3
3132 reflections(Δ/σ)max = 0.001
292 parametersΔρmax = 0.19 e Å3
0 restraintsΔρmin = 0.27 e Å3
Crystal data top
C19H21NO3γ = 76.872 (3)°
Mr = 311.37V = 799.89 (6) Å3
Triclinic, P1Z = 2
a = 7.2348 (2) ÅMo Kα radiation
b = 10.1212 (5) ŵ = 0.09 mm1
c = 11.6287 (6) ÅT = 120 K
α = 77.031 (2)°0.20 × 0.14 × 0.03 mm
β = 79.285 (3)°
Data collection top
Nonius KappaCCD area-detector
diffractometer
3132 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
2562 reflections with I > 2σ(I)
Tmin = 0.903, Tmax = 0.997Rint = 0.047
14845 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.117All H-atom parameters refined
S = 1.07Δρmax = 0.19 e Å3
3132 reflectionsΔρmin = 0.27 e Å3
292 parameters
Special details top

Experimental. The minimum and maximum absorption values stated above are those calculated in SHELXL97 from the given crystal dimensions. The ratio of minimum to maximum apparent transmission was determined experimentally as 0.772463.

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.53606 (19)0.30937 (14)0.42290 (12)0.0209 (3)
C20.3437 (2)0.36441 (17)0.43875 (15)0.0223 (4)
O20.24353 (17)0.36463 (13)0.53525 (11)0.0296 (3)
C30.2786 (2)0.41965 (19)0.31800 (15)0.0248 (4)
H310.206 (3)0.518 (2)0.3145 (18)0.033 (5)*
H320.186 (3)0.363 (2)0.3108 (18)0.035 (5)*
C3a0.4618 (2)0.40507 (17)0.22711 (15)0.0213 (4)
H3A0.450 (2)0.3570 (18)0.1666 (16)0.019 (4)*
C3b0.5317 (2)0.53744 (17)0.17369 (14)0.0202 (4)
C40.4436 (2)0.65604 (17)0.09400 (14)0.0214 (4)
O40.29576 (16)0.65975 (13)0.05405 (11)0.0287 (3)
C50.5429 (2)0.77911 (17)0.06436 (16)0.0231 (4)
H510.480 (3)0.836 (2)0.1238 (19)0.033 (5)*
H520.510 (3)0.837 (2)0.0145 (19)0.031 (5)*
C60.7623 (2)0.74438 (16)0.06188 (14)0.0202 (4)
C70.8135 (2)0.64350 (17)0.17734 (15)0.0213 (4)
H710.953 (3)0.6045 (19)0.1685 (17)0.027 (5)*
H720.790 (3)0.690 (2)0.2432 (19)0.030 (5)*
C7a0.7005 (2)0.53281 (16)0.20819 (13)0.0194 (3)
O80.76859 (15)0.41247 (11)0.27893 (10)0.0212 (3)
C8a0.6254 (2)0.32326 (17)0.29942 (14)0.0207 (4)
C90.8360 (3)0.87696 (18)0.05386 (17)0.0268 (4)
H910.978 (3)0.858 (2)0.0516 (17)0.030 (5)*
H920.780 (3)0.924 (2)0.125 (2)0.041 (6)*
H930.807 (3)0.946 (2)0.023 (2)0.041 (6)*
C100.8578 (2)0.67838 (18)0.04603 (15)0.0223 (4)
H1010.829 (3)0.746 (2)0.1224 (18)0.028 (5)*
H1020.811 (3)0.590 (2)0.0433 (17)0.030 (5)*
H1030.996 (3)0.6566 (19)0.0463 (16)0.024 (5)*
C110.7320 (3)0.18778 (19)0.26597 (17)0.0274 (4)
H1110.843 (3)0.149 (2)0.3114 (19)0.035 (5)*
H1120.784 (3)0.201 (2)0.179 (2)0.036 (5)*
H1130.644 (3)0.122 (2)0.2840 (19)0.037 (6)*
C120.6379 (2)0.23257 (17)0.51912 (14)0.0215 (4)
C130.5764 (3)0.11657 (18)0.59018 (16)0.0273 (4)
H130.461 (3)0.090 (2)0.5753 (18)0.031 (5)*
C140.6768 (3)0.03986 (19)0.68169 (16)0.0301 (4)
H140.636 (3)0.041 (2)0.7312 (19)0.034 (5)*
C150.8373 (3)0.07839 (19)0.70262 (16)0.0282 (4)
H150.909 (3)0.026 (2)0.766 (2)0.038 (6)*
C160.8983 (3)0.1942 (2)0.63108 (16)0.0288 (4)
H161.009 (3)0.224 (2)0.6464 (18)0.036 (5)*
C170.7987 (2)0.27232 (19)0.53922 (15)0.0256 (4)
H170.842 (3)0.356 (2)0.4875 (18)0.032 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0215 (7)0.0238 (7)0.0163 (7)0.0059 (5)0.0020 (5)0.0002 (6)
C20.0230 (9)0.0234 (8)0.0204 (9)0.0085 (7)0.0013 (7)0.0014 (7)
O20.0272 (7)0.0374 (7)0.0205 (6)0.0062 (5)0.0012 (5)0.0015 (5)
C30.0217 (9)0.0323 (10)0.0203 (9)0.0093 (7)0.0039 (7)0.0001 (7)
C3a0.0236 (9)0.0258 (8)0.0165 (8)0.0096 (7)0.0038 (6)0.0027 (7)
C3b0.0207 (8)0.0246 (8)0.0161 (8)0.0078 (6)0.0009 (6)0.0033 (7)
C40.0197 (8)0.0269 (9)0.0159 (8)0.0037 (7)0.0002 (6)0.0034 (7)
O40.0221 (6)0.0369 (7)0.0263 (7)0.0066 (5)0.0076 (5)0.0000 (5)
C50.0223 (9)0.0213 (8)0.0229 (9)0.0018 (7)0.0023 (7)0.0015 (7)
C60.0195 (8)0.0213 (8)0.0188 (8)0.0046 (6)0.0029 (6)0.0009 (7)
C70.0224 (9)0.0244 (8)0.0181 (8)0.0071 (7)0.0042 (6)0.0023 (7)
C7a0.0224 (8)0.0215 (8)0.0125 (7)0.0044 (6)0.0006 (6)0.0009 (6)
O80.0209 (6)0.0225 (6)0.0195 (6)0.0077 (5)0.0047 (4)0.0022 (5)
C8a0.0217 (8)0.0236 (8)0.0169 (8)0.0100 (6)0.0001 (6)0.0011 (7)
C90.0294 (10)0.0227 (9)0.0290 (10)0.0087 (7)0.0055 (8)0.0012 (8)
C100.0216 (9)0.0263 (9)0.0178 (9)0.0060 (7)0.0027 (6)0.0002 (7)
C110.0299 (10)0.0257 (9)0.0257 (10)0.0065 (8)0.0003 (8)0.0051 (7)
C120.0236 (9)0.0230 (8)0.0164 (8)0.0031 (6)0.0021 (6)0.0026 (7)
C130.0318 (10)0.0264 (9)0.0253 (9)0.0107 (7)0.0056 (7)0.0015 (7)
C140.0369 (10)0.0249 (9)0.0251 (9)0.0072 (8)0.0038 (8)0.0032 (8)
C150.0276 (9)0.0320 (10)0.0198 (9)0.0024 (7)0.0042 (7)0.0020 (7)
C160.0256 (9)0.0370 (10)0.0243 (9)0.0090 (8)0.0050 (7)0.0026 (8)
C170.0271 (9)0.0279 (9)0.0217 (9)0.0088 (7)0.0031 (7)0.0008 (7)
Geometric parameters (Å, º) top
N1—C21.371 (2)C7a—O81.3531 (19)
N1—C121.434 (2)O8—C8a1.4768 (19)
N1—C8a1.451 (2)C8a—C111.508 (2)
C2—O21.217 (2)C9—H911.00 (2)
C2—C31.510 (2)C9—H921.02 (2)
C3—C3a1.535 (2)C9—H931.03 (2)
C3—H311.01 (2)C10—H1011.02 (2)
C3—H321.00 (2)C10—H1021.02 (2)
C3a—C3b1.501 (2)C10—H1030.970 (19)
C3a—C8a1.552 (2)C11—H1111.00 (2)
C3a—H3A0.966 (18)C11—H1121.00 (2)
C3b—C7a1.343 (2)C11—H1130.99 (2)
C3b—C41.442 (2)C12—C131.387 (2)
C4—O41.233 (2)C12—C171.387 (2)
C4—C51.519 (2)C13—C141.387 (3)
C5—C61.542 (2)C13—H130.99 (2)
C5—H510.98 (2)C14—C151.383 (3)
C5—H521.01 (2)C14—H140.96 (2)
C6—C101.531 (2)C15—C161.387 (3)
C6—C91.531 (2)C15—H150.97 (2)
C6—C71.543 (2)C16—C171.390 (3)
C7—C7a1.476 (2)C16—H160.97 (2)
C7—H710.99 (2)C17—H171.00 (2)
C7—H720.96 (2)
C2—N1—C12122.99 (13)O8—C7a—C7118.76 (14)
C2—N1—C8a114.62 (13)C7a—O8—C8a107.56 (12)
C12—N1—C8a122.13 (13)N1—C8a—O8109.09 (12)
O2—C2—N1124.65 (15)N1—C8a—C11113.28 (14)
O2—C2—C3126.54 (15)O8—C8a—C11106.32 (13)
N1—C2—C3108.79 (14)N1—C8a—C3a104.50 (12)
C2—C3—C3a105.57 (13)O8—C8a—C3a106.50 (12)
C2—C3—H31109.6 (12)C11—C8a—C3a116.83 (14)
C3a—C3—H31113.8 (12)C6—C9—H91111.3 (11)
C2—C3—H32106.9 (12)C6—C9—H92112.9 (12)
C3a—C3—H32113.5 (12)H91—C9—H92106.1 (16)
H31—C3—H32107.3 (16)C6—C9—H93111.2 (12)
C3b—C3a—C3114.78 (14)H91—C9—H93106.2 (16)
C3b—C3a—C8a101.31 (12)H92—C9—H93108.7 (17)
C3—C3a—C8a106.02 (13)C6—C10—H101109.8 (11)
C3b—C3a—H3A111.8 (10)C6—C10—H102111.3 (11)
C3—C3a—H3A111.4 (10)H101—C10—H102109.3 (15)
C8a—C3a—H3A110.9 (10)C6—C10—H103109.0 (11)
C7a—C3b—C4121.34 (15)H101—C10—H103108.5 (15)
C7a—C3b—C3a110.20 (14)H102—C10—H103108.9 (15)
C4—C3b—C3a128.45 (14)C8a—C11—H111110.4 (12)
O4—C4—C3b122.94 (15)C8a—C11—H112110.8 (12)
O4—C4—C5121.70 (15)H111—C11—H112107.6 (16)
C3b—C4—C5115.34 (14)C8a—C11—H113109.5 (12)
C4—C5—C6115.74 (13)H111—C11—H113109.5 (17)
C4—C5—H51105.0 (12)H112—C11—H113109.1 (17)
C6—C5—H51111.6 (12)C13—C12—C17120.45 (16)
C4—C5—H52108.9 (11)C13—C12—N1119.28 (15)
C6—C5—H52109.9 (11)C17—C12—N1120.26 (15)
H51—C5—H52105.1 (16)C14—C13—C12119.66 (17)
C10—C6—C9109.47 (14)C14—C13—H13120.7 (12)
C10—C6—C5109.85 (14)C12—C13—H13119.7 (11)
C9—C6—C5109.47 (13)C15—C14—C13120.45 (17)
C10—C6—C7109.56 (13)C15—C14—H14119.1 (12)
C9—C6—C7108.66 (13)C13—C14—H14120.5 (12)
C5—C6—C7109.81 (13)C14—C15—C16119.60 (16)
C7a—C7—C6111.06 (13)C14—C15—H15121.7 (13)
C7a—C7—H71111.0 (11)C16—C15—H15118.7 (13)
C6—C7—H71109.9 (11)C15—C16—C17120.55 (17)
C7a—C7—H72108.0 (12)C15—C16—H16120.4 (12)
C6—C7—H72111.5 (12)C17—C16—H16119.0 (12)
H71—C7—H72105.2 (16)C12—C17—C16119.29 (16)
C3b—C7a—O8114.40 (14)C12—C17—H17119.8 (11)
C3b—C7a—C7126.84 (15)C16—C17—H17120.9 (11)
C12—N1—C2—O26.6 (3)C3b—C7a—O8—C8a1.99 (18)
C8a—N1—C2—O2179.12 (15)C7—C7a—O8—C8a177.73 (13)
C12—N1—C2—C3171.82 (14)C2—N1—C8a—O8115.76 (14)
C8a—N1—C2—C32.48 (19)C12—N1—C8a—O869.88 (18)
O2—C2—C3—C3a175.55 (16)C2—N1—C8a—C11126.03 (16)
N1—C2—C3—C3a6.09 (18)C12—N1—C8a—C1148.3 (2)
C2—C3—C3a—C3b103.74 (16)C2—N1—C8a—C3a2.19 (17)
C2—C3—C3a—C8a7.19 (17)C12—N1—C8a—C3a176.54 (14)
C3—C3a—C3b—C7a113.68 (16)C7a—O8—C8a—N1110.43 (14)
C8a—C3a—C3b—C7a0.04 (17)C7a—O8—C8a—C11127.08 (14)
C3—C3a—C3b—C467.8 (2)C7a—O8—C8a—C3a1.83 (16)
C8a—C3a—C3b—C4178.44 (16)C3b—C3a—C8a—N1114.34 (13)
C7a—C3b—C4—O4174.77 (15)C3—C3a—C8a—N15.80 (16)
C3a—C3b—C4—O43.6 (3)C3b—C3a—C8a—O81.06 (15)
C7a—C3b—C4—C56.7 (2)C3—C3a—C8a—O8121.20 (13)
C3a—C3b—C4—C5174.97 (15)C3b—C3a—C8a—C11119.63 (15)
O4—C4—C5—C6149.83 (15)C3—C3a—C8a—C11120.23 (16)
C3b—C4—C5—C631.6 (2)C2—N1—C12—C1356.7 (2)
C4—C5—C6—C1070.11 (18)C8a—N1—C12—C13117.21 (17)
C4—C5—C6—C9169.66 (14)C2—N1—C12—C17124.69 (18)
C4—C5—C6—C750.45 (19)C8a—N1—C12—C1761.4 (2)
C10—C6—C7—C7a76.86 (17)C17—C12—C13—C140.1 (3)
C9—C6—C7—C7a163.57 (14)N1—C12—C13—C14178.51 (16)
C5—C6—C7—C7a43.87 (18)C12—C13—C14—C150.1 (3)
C4—C3b—C7a—O8177.32 (14)C13—C14—C15—C160.3 (3)
C3a—C3b—C7a—O81.29 (19)C14—C15—C16—C170.5 (3)
C4—C3b—C7a—C73.0 (3)C13—C12—C17—C160.3 (3)
C3a—C3b—C7a—C7178.41 (15)N1—C12—C17—C16178.33 (15)
C6—C7—C7a—C3b22.9 (2)C15—C16—C17—C120.5 (3)
C6—C7—C7a—O8157.41 (14)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C17—H17···O81.00 (2)2.49 (2)3.066 (2)116 (2)
C7—H72···O2i0.96 (2)2.49 (2)3.275 (2)140 (2)
C16—H16···O2ii0.98 (2)2.46 (2)3.243 (3)138 (2)
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+1, y, z.
(III) 6,6,8a-trimethyl-1-(3-pyridyl)-3a,6,7,8a-tetrahydro- 1H-[1]benzofuro[2,3-b]pyrrole-2,4(3H,5H)-dione top
Crystal data top
C18H20N2O3Z = 2
Mr = 312.36F(000) = 332
Triclinic, P1Dx = 1.333 Mg m3
Hall symbol: -P 1Melting point: 198(1) K
a = 7.2330 (2) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.8165 (3) ÅCell parameters from 3489 reflections
c = 11.6008 (3) Åθ = 2.9–27.5°
α = 78.541 (2)°µ = 0.09 mm1
β = 78.992 (2)°T = 120 K
γ = 77.302 (1)°Prism, colourless
V = 778.13 (4) Å30.19 × 0.14 × 0.09 mm
Data collection top
Nonius KappaCCD area-detector
diffractometer
3040 independent reflections
Radiation source: Bruker Nonius FR591 rotating anode2769 reflections with I > 2σ(I)
10 cm confocal mirrors monochromatorRint = 0.035
Detector resolution: 9.091 pixels mm-1θmax = 26.0°, θmin = 3.0°
ϕ and ω scansh = 88
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
k = 1212
Tmin = 0.913, Tmax = 0.992l = 1413
13914 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.039Hydrogen site location: difference Fourier map
wR(F2) = 0.104All H-atom parameters refined
S = 1.07 w = 1/[σ2(Fo2) + (0.0478P)2 + 0.3717P]
where P = (Fo2 + 2Fc2)/3
3040 reflections(Δ/σ)max = 0.006
288 parametersΔρmax = 0.29 e Å3
0 restraintsΔρmin = 0.20 e Å3
Crystal data top
C18H20N2O3γ = 77.302 (1)°
Mr = 312.36V = 778.13 (4) Å3
Triclinic, P1Z = 2
a = 7.2330 (2) ÅMo Kα radiation
b = 9.8165 (3) ŵ = 0.09 mm1
c = 11.6008 (3) ÅT = 120 K
α = 78.541 (2)°0.19 × 0.14 × 0.09 mm
β = 78.992 (2)°
Data collection top
Nonius KappaCCD area-detector
diffractometer
3040 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
2769 reflections with I > 2σ(I)
Tmin = 0.913, Tmax = 0.992Rint = 0.035
13914 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.104All H-atom parameters refined
S = 1.07Δρmax = 0.29 e Å3
3040 reflectionsΔρmin = 0.20 e Å3
288 parameters
Special details top

Experimental. The minimum and maximum absorption values stated above are those calculated in SHELXL97 from the given crystal dimensions. The ratio of minimum to maximum apparent transmission was determined experimentally as 0.897023.

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.52665 (16)0.30837 (12)0.41917 (10)0.0176 (3)
C20.33267 (19)0.36189 (14)0.43603 (12)0.0192 (3)
O20.23076 (14)0.35965 (11)0.53250 (9)0.0266 (3)
C30.2698 (2)0.41948 (16)0.31608 (12)0.0212 (3)
H310.199 (3)0.522 (2)0.3150 (16)0.031 (4)*
H320.180 (3)0.3629 (19)0.3075 (16)0.031 (4)*
C3a0.45417 (18)0.40606 (14)0.22483 (12)0.0175 (3)
H3A0.445 (2)0.3544 (17)0.1614 (14)0.020 (4)*
C3b0.52623 (18)0.54125 (14)0.17524 (11)0.0169 (3)
C40.44123 (18)0.66200 (14)0.09692 (11)0.0179 (3)
O40.29262 (14)0.66625 (11)0.05789 (9)0.0253 (3)
C50.54395 (19)0.78688 (14)0.06719 (13)0.0197 (3)
H510.484 (2)0.8465 (19)0.1277 (16)0.029 (4)*
H520.512 (2)0.8426 (19)0.0123 (16)0.031 (4)*
C60.76353 (18)0.74878 (13)0.06428 (11)0.0163 (3)
C70.81269 (19)0.64704 (14)0.17855 (12)0.0172 (3)
H710.951 (3)0.6059 (18)0.1696 (15)0.026 (4)*
H720.790 (2)0.6981 (17)0.2473 (15)0.024 (4)*
C7a0.69611 (18)0.53467 (14)0.20903 (11)0.0156 (3)
O80.76186 (13)0.41105 (10)0.27684 (8)0.0178 (2)
C8a0.61651 (19)0.32125 (14)0.29524 (11)0.0176 (3)
C90.8411 (2)0.88351 (15)0.05682 (14)0.0231 (3)
H910.981 (3)0.8597 (18)0.0549 (15)0.027 (4)*
H920.785 (3)0.931 (2)0.1271 (17)0.033 (5)*
H930.812 (3)0.9530 (19)0.0187 (17)0.030 (4)*
C100.8581 (2)0.67893 (15)0.04465 (12)0.0187 (3)
H1010.827 (2)0.7468 (18)0.1199 (15)0.024 (4)*
H1020.813 (2)0.5911 (18)0.0417 (14)0.021 (4)*
H1031.000 (2)0.6569 (18)0.0462 (15)0.025 (4)*
C110.7167 (2)0.18111 (15)0.25856 (13)0.0230 (3)
H1110.822 (3)0.1352 (19)0.3050 (17)0.033 (5)*
H1120.770 (3)0.1982 (19)0.1741 (17)0.031 (4)*
H1130.622 (3)0.1204 (19)0.2701 (16)0.030 (4)*
C120.62667 (19)0.23041 (14)0.51338 (12)0.0194 (3)
C130.5574 (2)0.11635 (16)0.58656 (13)0.0246 (3)
H130.434 (3)0.0919 (18)0.5760 (15)0.028 (4)*
N140.64495 (19)0.03434 (14)0.67481 (12)0.0292 (3)
C150.8073 (2)0.06686 (17)0.69164 (13)0.0282 (3)
H150.871 (3)0.0038 (19)0.7574 (17)0.033 (5)*
C160.8863 (2)0.17848 (17)0.62335 (13)0.0278 (3)
H161.002 (3)0.197 (2)0.6422 (18)0.041 (5)*
C170.7942 (2)0.26320 (16)0.53253 (13)0.0239 (3)
H170.843 (3)0.346 (2)0.4835 (16)0.032 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0170 (6)0.0212 (6)0.0135 (5)0.0048 (4)0.0015 (4)0.0000 (4)
C20.0192 (7)0.0203 (7)0.0186 (7)0.0073 (5)0.0019 (5)0.0013 (5)
O20.0218 (5)0.0363 (6)0.0179 (5)0.0046 (4)0.0027 (4)0.0022 (4)
C30.0159 (7)0.0304 (8)0.0176 (7)0.0084 (6)0.0024 (5)0.0005 (6)
C3a0.0172 (7)0.0217 (7)0.0147 (6)0.0079 (5)0.0026 (5)0.0011 (5)
C3b0.0163 (6)0.0202 (7)0.0145 (6)0.0062 (5)0.0003 (5)0.0023 (5)
C40.0134 (6)0.0230 (7)0.0159 (6)0.0020 (5)0.0006 (5)0.0037 (5)
O40.0169 (5)0.0323 (6)0.0262 (5)0.0060 (4)0.0074 (4)0.0018 (4)
C50.0161 (7)0.0182 (7)0.0228 (7)0.0013 (5)0.0017 (5)0.0017 (6)
C60.0149 (6)0.0163 (6)0.0175 (6)0.0032 (5)0.0025 (5)0.0018 (5)
C70.0158 (7)0.0210 (7)0.0158 (6)0.0058 (5)0.0028 (5)0.0027 (5)
C7a0.0165 (6)0.0180 (6)0.0110 (6)0.0025 (5)0.0003 (5)0.0019 (5)
O80.0159 (5)0.0190 (5)0.0183 (5)0.0063 (4)0.0038 (4)0.0021 (4)
C8a0.0171 (6)0.0209 (7)0.0153 (6)0.0088 (5)0.0001 (5)0.0009 (5)
C90.0230 (7)0.0175 (7)0.0294 (8)0.0065 (6)0.0047 (6)0.0019 (6)
C100.0174 (7)0.0215 (7)0.0168 (7)0.0054 (5)0.0014 (5)0.0016 (5)
C110.0242 (7)0.0213 (7)0.0219 (7)0.0057 (6)0.0023 (6)0.0037 (6)
C120.0200 (7)0.0212 (7)0.0157 (6)0.0023 (5)0.0015 (5)0.0028 (5)
C130.0241 (7)0.0250 (7)0.0235 (7)0.0060 (6)0.0030 (6)0.0002 (6)
N140.0289 (7)0.0285 (7)0.0257 (7)0.0057 (5)0.0028 (5)0.0053 (5)
C150.0227 (7)0.0333 (8)0.0218 (7)0.0012 (6)0.0017 (6)0.0027 (6)
C160.0212 (7)0.0364 (9)0.0241 (7)0.0046 (6)0.0047 (6)0.0011 (6)
C170.0232 (7)0.0273 (8)0.0206 (7)0.0077 (6)0.0024 (6)0.0006 (6)
Geometric parameters (Å, º) top
N1—C21.3765 (18)C7—H720.993 (17)
N1—C121.4247 (17)C7a—O81.3518 (16)
N1—C8a1.4535 (16)O8—C8a1.4748 (15)
C2—O21.2159 (17)C8a—C111.5084 (19)
C2—C31.5096 (19)C9—H910.987 (18)
C3—C3a1.5348 (18)C9—H920.996 (19)
C3—H311.024 (19)C9—H931.023 (19)
C3—H320.972 (18)C10—H1011.017 (17)
C3a—C3b1.5001 (18)C10—H1020.980 (17)
C3a—C8a1.5508 (18)C10—H1031.001 (17)
C3a—H3A0.991 (16)C11—H1110.990 (19)
C3b—C7a1.3440 (18)C11—H1120.977 (19)
C3b—C41.4400 (19)C11—H1130.978 (18)
C4—O41.2332 (16)C12—C171.387 (2)
C4—C51.5193 (19)C12—C131.390 (2)
C5—C61.5450 (18)C13—N141.339 (2)
C5—H510.979 (19)C13—H131.011 (18)
C5—H521.014 (18)N14—C151.340 (2)
C6—C91.5276 (18)C15—C161.383 (2)
C6—C101.5307 (18)C15—H150.999 (19)
C6—C71.5424 (18)C16—C171.386 (2)
C7—C7a1.4809 (18)C16—H160.97 (2)
C7—H710.988 (18)C17—H170.987 (19)
C2—N1—C12122.90 (11)C3b—C7a—C7126.46 (12)
C2—N1—C8a114.39 (11)O8—C7a—C7119.08 (11)
C12—N1—C8a122.22 (11)C7a—O8—C8a107.46 (10)
O2—C2—N1124.65 (13)N1—C8a—O8108.62 (10)
O2—C2—C3126.56 (13)N1—C8a—C11113.18 (11)
N1—C2—C3108.78 (11)O8—C8a—C11107.49 (11)
C2—C3—C3a105.67 (11)N1—C8a—C3a104.53 (10)
C2—C3—H31109.5 (10)O8—C8a—C3a106.66 (10)
C3a—C3—H31112.7 (10)C11—C8a—C3a116.01 (11)
C2—C3—H32106.5 (11)C6—C9—H91109.6 (10)
C3a—C3—H32114.0 (10)C6—C9—H92111.7 (10)
H31—C3—H32108.2 (14)H91—C9—H92107.4 (14)
C3b—C3a—C3115.39 (11)C6—C9—H93110.7 (10)
C3b—C3a—C8a101.22 (10)H91—C9—H93108.4 (14)
C3—C3a—C8a106.03 (10)H92—C9—H93108.8 (14)
C3b—C3a—H3A112.2 (9)C6—C10—H101109.4 (9)
C3—C3a—H3A111.8 (9)C6—C10—H102111.0 (10)
C8a—C3a—H3A109.3 (9)H101—C10—H102109.2 (13)
C7a—C3b—C4121.61 (12)C6—C10—H103108.8 (10)
C7a—C3b—C3a110.16 (12)H101—C10—H103109.3 (13)
C4—C3b—C3a128.14 (12)H102—C10—H103109.2 (13)
O4—C4—C3b122.78 (12)C8a—C11—H111111.4 (11)
O4—C4—C5121.56 (12)C8a—C11—H112108.2 (10)
C3b—C4—C5115.64 (11)H111—C11—H112109.2 (15)
C4—C5—C6115.43 (11)C8a—C11—H113108.4 (10)
C4—C5—H51105.2 (10)H111—C11—H113110.5 (15)
C6—C5—H51110.6 (10)H112—C11—H113109.0 (14)
C4—C5—H52107.6 (10)C17—C12—C13118.92 (13)
C6—C5—H52110.3 (10)C17—C12—N1121.76 (12)
H51—C5—H52107.2 (14)C13—C12—N1119.30 (12)
C9—C6—C10109.13 (11)N14—C13—C12123.51 (14)
C9—C6—C7108.67 (11)N14—C13—H13116.0 (10)
C10—C6—C7109.63 (11)C12—C13—H13120.5 (10)
C9—C6—C5109.37 (11)C13—N14—C15116.82 (13)
C10—C6—C5109.79 (11)N14—C15—C16123.55 (14)
C7—C6—C5110.22 (11)N14—C15—H15115.5 (10)
C7a—C7—C6111.02 (10)C16—C15—H15120.9 (10)
C7a—C7—H71111.0 (10)C15—C16—C17119.23 (14)
C6—C7—H71110.4 (10)C15—C16—H16118.9 (12)
C7a—C7—H72108.4 (10)C17—C16—H16121.8 (12)
C6—C7—H72111.4 (10)C16—C17—C12117.96 (14)
H71—C7—H72104.5 (14)C16—C17—H17121.7 (10)
C3b—C7a—O8114.46 (12)C12—C17—H17120.3 (10)
C12—N1—C2—O26.8 (2)C3b—C7a—O8—C8a1.64 (14)
C8a—N1—C2—O2178.94 (13)C7—C7a—O8—C8a178.71 (11)
C12—N1—C2—C3171.98 (12)C2—N1—C8a—O8118.20 (12)
C8a—N1—C2—C30.17 (16)C12—N1—C8a—O869.59 (15)
O2—C2—C3—C3a176.29 (14)C2—N1—C8a—C11122.50 (13)
N1—C2—C3—C3a4.97 (15)C12—N1—C8a—C1149.71 (17)
C2—C3—C3a—C3b103.61 (13)C2—N1—C8a—C3a4.63 (14)
C2—C3—C3a—C8a7.53 (14)C12—N1—C8a—C3a176.84 (11)
C3—C3a—C3b—C7a114.58 (13)C7a—O8—C8a—N1110.22 (11)
C8a—C3a—C3b—C7a0.63 (14)C7a—O8—C8a—C11126.99 (11)
C3—C3a—C3b—C468.84 (17)C7a—O8—C8a—C3a1.94 (13)
C8a—C3a—C3b—C4177.22 (13)C3b—C3a—C8a—N1113.43 (11)
C7a—C3b—C4—O4174.65 (12)C3—C3a—C8a—N17.36 (13)
C3a—C3b—C4—O41.6 (2)C3b—C3a—C8a—O81.52 (12)
C7a—C3b—C4—C56.80 (18)C3—C3a—C8a—O8122.31 (11)
C3a—C3b—C4—C5176.96 (12)C3b—C3a—C8a—C11121.20 (12)
O4—C4—C5—C6150.29 (12)C3—C3a—C8a—C11118.01 (13)
C3b—C4—C5—C631.15 (16)C2—N1—C12—C17130.19 (15)
C4—C5—C6—C9169.41 (11)C8a—N1—C12—C1758.26 (18)
C4—C5—C6—C1070.87 (14)C2—N1—C12—C1351.31 (18)
C4—C5—C6—C750.00 (15)C8a—N1—C12—C13120.23 (14)
C9—C6—C7—C7a163.72 (11)C17—C12—C13—N140.7 (2)
C10—C6—C7—C7a77.08 (13)N1—C12—C13—N14177.84 (13)
C5—C6—C7—C7a43.89 (14)C12—C13—N14—C150.3 (2)
C4—C3b—C7a—O8176.24 (11)C13—N14—C15—C160.1 (2)
C3a—C3b—C7a—O80.61 (16)N14—C15—C16—C170.4 (2)
C4—C3b—C7a—C73.4 (2)C15—C16—C17—C120.8 (2)
C3a—C3b—C7a—C7179.78 (12)C13—C12—C17—C160.9 (2)
C6—C7—C7a—C3b23.15 (18)N1—C12—C17—C16177.56 (13)
C6—C7—C7a—O8156.45 (11)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C17—H17···O80.99 (2)2.50 (2)3.060 (2)116 (2)
C7—H72···O2i0.99 (2)2.49 (2)3.295 (2)138 (1)
C16—H16···O2ii0.97 (2)2.54 (2)3.268 (2)132 (2)
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+1, y, z.

Experimental details

(I)(II)(III)
Crystal data
Chemical formulaC19H27NO3C19H21NO3C18H20N2O3
Mr317.42311.37312.36
Crystal system, space groupTriclinic, P1Triclinic, P1Triclinic, P1
Temperature (K)120120120
a, b, c (Å)9.4708 (2), 10.2139 (2), 10.7512 (2)7.2348 (2), 10.1212 (5), 11.6287 (6)7.2330 (2), 9.8165 (3), 11.6008 (3)
α, β, γ (°)105.804 (1), 99.141 (1), 116.320 (1)77.031 (2), 79.285 (3), 76.872 (3)78.541 (2), 78.992 (2), 77.302 (1)
V3)848.50 (3)799.89 (6)778.13 (4)
Z222
Radiation typeMo KαMo KαMo Kα
µ (mm1)0.080.090.09
Crystal size (mm)0.24 × 0.16 × 0.030.20 × 0.14 × 0.030.19 × 0.14 × 0.09
Data collection
DiffractometerNonius KappaCCD area-detector
diffractometer
Nonius KappaCCD area-detector
diffractometer
Nonius KappaCCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2003)
Multi-scan
(SADABS; Sheldrick, 2003)
Multi-scan
(SADABS; Sheldrick, 2003)
Tmin, Tmax0.891, 0.9980.903, 0.9970.913, 0.992
No. of measured, independent and
observed [I > 2σ(I)] reflections
18064, 3327, 2990 14845, 3132, 2562 13914, 3040, 2769
Rint0.0390.0470.035
(sin θ/λ)max1)0.6170.6170.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.107, 1.12 0.044, 0.117, 1.07 0.039, 0.104, 1.07
No. of reflections332731323040
No. of parameters316292288
H-atom treatmentAll H-atom parameters refinedAll H-atom parameters refinedAll H-atom parameters refined
Δρmax, Δρmin (e Å3)0.30, 0.320.19, 0.270.29, 0.20

Computer programs: COLLECT (Nonius, 1998), DENZO (Otwinowski & Minor, 1997) and COLLECT, DENZO and COLLECT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEPIII (Farrugia, 1997), PLATON (Spek, 2003) and INSIGHTII (Accelrys, 2002), SHELXL97 and PLATON).

Hydrogen-bond geometry (Å, º) for (I) top
D—H···AD—HH···AD···AD—H···A
C12—H12···O81.00 (2)2.52 (2)2.920 (2)103 (1)
C17—H171···O21.01 (2)2.55 (2)3.153 (2)118 (1)
Hydrogen-bond geometry (Å, º) for (II) top
D—H···AD—HH···AD···AD—H···A
C17—H17···O81.00 (2)2.49 (2)3.066 (2)116 (2)
C7—H72···O2i0.96 (2)2.49 (2)3.275 (2)140 (2)
C16—H16···O2ii0.98 (2)2.46 (2)3.243 (3)138 (2)
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+1, y, z.
Hydrogen-bond geometry (Å, º) for (III) top
D—H···AD—HH···AD···AD—H···A
C17—H17···O80.99 (2)2.50 (2)3.060 (2)116 (2)
C7—H72···O2i0.99 (2)2.49 (2)3.295 (2)138 (1)
C16—H16···O2ii0.97 (2)2.54 (2)3.268 (2)132 (2)
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+1, y, z.
 

Acknowledgements

The authors thank the EPSRC National Crystallography Service, Southampton, England.

References

First citationAccelrys (2002). INSIGHTII. Version 2000.2. Accelrys Inc., 9685 Scranton Road, San Diego, CA 92121-3752, USA.  Google Scholar
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