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

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1,10,10-Tri­methyl-5-phenyl-3-oxa-4-aza­tri­cyclo­[5.2.1.02,6]dec-4-en-2-ol

aLaboratoire de Chimie de Coordination, Faculté des Sciences-Semlalia, BP 2390, 40001 Marrakech, Morocco, bLaboratoire des Matériaux Inorganiques, UMR CNRS 6002, Université Blaise Pascal, 24 Avenue des Landais, 63177 Aubière, France, and cLaboratoire de Chimie des Substances Naturelles, Unité Associé au CNRST (URAC16), Faculté des Sciences-Semlalia, BP 2390, Boulevard My Abdellah, 40000 Marrakech, Morocco
*Correspondence e-mail: berraho@uca.ma

(Received 10 July 2013; accepted 19 July 2013; online 24 July 2013)

The title compound, C17H21NO2, was synthesized by the reaction of (1R)-(+)-3-benzyl­camphor and hydroxyl­amine. The oxazole ring makes a dihedral angle of 23.42 (16)° with the phenyl ring. The six-membered ring of the norboryl group adopts a boat conformation, whereas each of the five-membered rings of the norboryl group displays a flattened envelope conformation, with the C atom carrying the methyl groups representing the flap for both rings. In the crystal, mol­ecules are linked into zigzag chains propagating along the b axis by O—H⋯N hydrogen bonds.

Related literature

For the functionalization of camphor, see: Jennings & Herschbach (1965[Jennings, B. H. & Herschbach, G. B. (1965). J. Org. Chem. 30, 3902-3909.]); Pastrán et al., (2011[Pastrán, J., Ineichen, E., Agrifoglio, G., Linden, A. & Dorta, R. (2011). Acta Cryst. E67, o188-o189.]). For transition metal complexes of camphor, see: Spannenberg et al. (2002[Spannenberg, A., Fdil, N., El Firdoussi, L. & Karim, A. (2002). Z. Kristallogr. New Cryst. Struct. 217, 549-550.]); Harrad et al. (2010[Harrad, M. A., Valerga, P., Puerta, M. C., Ali, M. A., El Firdoussi, L. & Karim, A. (2010). Acta Cryst. E66, m281.]); Ait Ali et al. (2006[Ait Ali, M., Karim, A., Castanet, Y., Mortreux, A. & Mentré, O. (2006). Acta Cryst. E62, m3160-m3162.]); Gaudo et al. (2011[Gaudo, T., Bleifu, S. M., Müller, A. L., Roth, T., Hoffmann, S., Heinemann, W. F. & Burzlaff, N. (2011). Dalton Trans. 40, 6547-6554.]). For ring-puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C17H21NO2

  • Mr = 271.35

  • Monoclinic, C 2

  • a = 22.1681 (18) Å

  • b = 6.6134 (5) Å

  • c = 10.7358 (8) Å

  • β = 108.277 (3)°

  • V = 1494.5 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 296 K

  • 0.58 × 0.34 × 0.14 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) Tmin = 0.627, Tmax = 0.745

  • 4379 measured reflections

  • 1350 independent reflections

  • 1220 reflections with I > 2σ(I)

  • Rint = 0.025

Refinement
  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.106

  • S = 1.08

  • 1350 reflections

  • 186 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.24 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2⋯N2i 0.82 2.06 2.877 (3) 174
Symmetry code: (i) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.])and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information


Comment top

The versatility and importance of camphor as a chiral starting material in the synthesis of natural products is primarily due to the availability of methods for the introduction of functional groups (Jennings & Herschbach, 1965; Pastrán et al., 2011). We have developed a series of complexes based on camphor 1,3-diketonato ligands (Spannenberg et al., 2002; Harrad et al., 2010; Ait Ali et al., 2006), and their application in catalytic asymmetric reactions has been described (Gaudo et al., 2011). In this work, we present the structure of a new heterocyclic compound (1,10,10-trimethyl-5-phenyl-3-oxa-4-aza-tricyclo[5.2.1.02,6]dec-4- en-2-ol)) which we have synthesized by hetercyclization from benzylcamphor with hydroxylamine. In the molecule (Fig. 1), the six-membered ring of the norboryl system adopts a boat conformation, as indicated by Cremer & Pople (1975) puckering parameters Q = 0.966 (3) Å and spherical polar angle θ = 89.71 (17)° with ϕ = 121.07 (19)°. The two fused five-membered rings display an envelope conformation with Q = 0.602 (3) Å and ϕ = 287.7 (3)° for the first ring (C6, C7, C9, C10, C12) and Q = 0.590 (4) Å and ϕ = 37.7 (4)° for the other ring (C7, C10, C12, C14, C19). In the crystal structure, molecules are linked into zigzag chains (Fig. 2) running along the b axis by intermolecular O—H···N hydrogen bonds (Table 1).

Related literature top

For the functionalization of camphor, see: Jennings & Herschbach (1965); Pastrán et al., (2011). For transition metal complexes of camphor, see: Spannenberg et al. (2002); Harrad et al. (2010); Ait Ali et al. (2006); Gaudo et al. (2011). For ring-puckering parameters, see: Cremer & Pople (1975).

Experimental top

(1R)-(+)-3-benzyl-camphor (1 mmol), and hydroxylamine (2 mmol), in dichloromethane (10 ml) were vigorously stirred at reflux. The progress of the reaction was followed by TLC. The reaction went to completion after 24 h. After completion of the reaction, the mixture was diluted with H2O (10 ml) and extracted with EtOAc (2 × 10 ml) and dried over Na2SO4. The title compound was isolated as a white powder by column chromatography on silica gel using ethyl acetate–n-hexane as eluant (yield 79%; m.p. = 145°C). Colourless single crystals suitable for X-ray analysis were obtained by slow evaporation of n-hexane solution.

Refinement top

All H atoms were fixed geometrically and treated as riding with O—H = 0.82 Å, C—H = 0.96 Å (methyl), 0.97 Å (methylene), 0.98 Å (methine) with Uiso(H) = 1.2Ueq(methylene, methine) or Uiso(H) = 1.5Ueq(methyl). The torsion angle about the C—O bond of the hydroxyl group was refined. In the absence of significant anomalous scattering, the absolute configuration could not be reliably determined and thus Friedel pairs were merged and any references to the Flack parameter were removed.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012)and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability. level. H atoms are represented as small spheres of arbitrary radii.
[Figure 2] Fig. 2. Partial packing view showing the O—H···N and N—H···N interactions (dashed lines) and the formation of a chain parallel to the b axis. H atoms not involved in hydrogen bonding have been omitted for clarity.
1,10,10-Trimethyl-5-phenyl-3-oxa-4-azatricyclo[5.2.1.02,6]dec-4-en-2-ol top
Crystal data top
C17H21NO2F(000) = 584
Mr = 271.35Dx = 1.202 Mg m3
Monoclinic, C2Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C 2yCell parameters from 2921 reflections
a = 22.1681 (18) Åθ = 3.2–24.5°
b = 6.6134 (5) ŵ = 0.08 mm1
c = 10.7358 (8) ÅT = 296 K
β = 108.277 (3)°Plaquet, colourless
V = 1494.5 (2) Å30.58 × 0.34 × 0.14 mm
Z = 4
Data collection top
Bruker APEXII CCD
diffractometer
1350 independent reflections
Radiation source: fine-focus sealed tube1220 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
Detector resolution: 8.3333 pixels mm-1θmax = 24.5°, θmin = 3.2°
ω and ϕ scansh = 2525
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008)
k = 67
Tmin = 0.627, Tmax = 0.745l = 1212
4379 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.042H-atom parameters constrained
wR(F2) = 0.106 w = 1/[σ2(Fo2) + (0.0701P)2 + 0.2932P]
where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max < 0.001
1350 reflectionsΔρmax = 0.29 e Å3
186 parametersΔρmin = 0.24 e Å3
1 restraintExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.050 (5)
Crystal data top
C17H21NO2V = 1494.5 (2) Å3
Mr = 271.35Z = 4
Monoclinic, C2Mo Kα radiation
a = 22.1681 (18) ŵ = 0.08 mm1
b = 6.6134 (5) ÅT = 296 K
c = 10.7358 (8) Å0.58 × 0.34 × 0.14 mm
β = 108.277 (3)°
Data collection top
Bruker APEXII CCD
diffractometer
1350 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008)
1220 reflections with I > 2σ(I)
Tmin = 0.627, Tmax = 0.745Rint = 0.025
4379 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0421 restraint
wR(F2) = 0.106H-atom parameters constrained
S = 1.08Δρmax = 0.29 e Å3
1350 reflectionsΔρmin = 0.24 e Å3
186 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
C50.81485 (10)0.9730 (4)0.0870 (2)0.0383 (6)
C60.85865 (11)1.0215 (4)0.0464 (2)0.0393 (6)
H60.86091.16730.06370.047*
C70.92540 (11)0.9251 (5)0.0815 (2)0.0527 (8)
H70.95691.00840.05850.063*
C80.91859 (14)0.7103 (6)0.0251 (3)0.0632 (9)
H8A0.89240.70880.06620.076*
H8B0.95970.65200.03250.076*
C90.88635 (13)0.5975 (5)0.1116 (3)0.0560 (7)
H9A0.91220.48440.15570.067*
H9B0.84500.54730.05980.067*
C10.87986 (11)0.7567 (4)0.2119 (2)0.0445 (7)
C20.82786 (10)0.9070 (4)0.1358 (2)0.0387 (6)
C100.94087 (11)0.8860 (5)0.2308 (2)0.0520 (7)
C121.00340 (13)0.7670 (7)0.2908 (3)0.0777 (11)
H12A1.03810.84120.27750.116*
H12B1.00010.63740.24900.116*
H12C1.01070.74870.38310.116*
C110.94630 (15)1.0792 (6)0.3124 (3)0.0690 (9)
H11A0.98521.14750.31750.104*
H11B0.94611.04480.39910.104*
H11C0.91101.16640.27160.104*
C130.82295 (11)1.0459 (5)0.2104 (2)0.0443 (6)
C180.79751 (13)0.9407 (6)0.3273 (2)0.0586 (8)
H180.77460.82250.32870.070*
C170.80638 (16)1.0122 (7)0.4421 (3)0.0738 (12)
H170.78890.94150.52010.089*
C160.83984 (16)1.1823 (8)0.4422 (3)0.0794 (12)
H160.84611.22690.51930.095*
C150.86471 (18)1.2897 (8)0.3279 (4)0.0852 (12)
H150.88701.40860.32830.102*
C140.85657 (16)1.2210 (6)0.2119 (3)0.0671 (9)
H140.87391.29350.13470.080*
C190.86922 (15)0.6664 (6)0.3337 (3)0.0625 (9)
H19A0.82940.59580.30920.094*
H19B0.86860.77260.39420.094*
H19C0.90300.57380.37450.094*
O10.77279 (7)0.8072 (3)0.04364 (16)0.0467 (5)
N20.77018 (9)0.8524 (4)0.08639 (18)0.0438 (6)
O20.80582 (8)1.0188 (3)0.22155 (14)0.0519 (6)
H20.78641.11780.18330.078*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C50.0383 (11)0.0409 (14)0.0357 (11)0.0014 (11)0.0116 (9)0.0065 (11)
C60.0455 (12)0.0374 (14)0.0336 (11)0.0048 (11)0.0103 (9)0.0014 (11)
C70.0380 (12)0.070 (2)0.0502 (14)0.0076 (14)0.0144 (10)0.0066 (15)
C80.0559 (15)0.075 (2)0.0647 (17)0.0157 (17)0.0276 (13)0.0043 (17)
C90.0555 (14)0.0465 (17)0.0643 (17)0.0097 (14)0.0165 (12)0.0061 (15)
C10.0451 (12)0.0443 (17)0.0422 (13)0.0041 (12)0.0109 (10)0.0047 (12)
C20.0386 (11)0.0430 (16)0.0341 (11)0.0009 (11)0.0107 (9)0.0011 (11)
C100.0428 (12)0.059 (2)0.0478 (13)0.0021 (14)0.0047 (10)0.0047 (15)
C120.0453 (14)0.098 (3)0.077 (2)0.0091 (18)0.0011 (13)0.015 (2)
C110.0690 (17)0.068 (2)0.0520 (16)0.0134 (19)0.0069 (12)0.0013 (17)
C130.0453 (12)0.0521 (17)0.0358 (12)0.0018 (13)0.0130 (9)0.0030 (12)
C180.0577 (14)0.078 (2)0.0395 (13)0.0028 (16)0.0148 (11)0.0094 (15)
C170.0720 (18)0.116 (4)0.0356 (14)0.009 (2)0.0197 (13)0.0077 (18)
C160.0704 (19)0.126 (4)0.0463 (17)0.013 (2)0.0247 (14)0.024 (2)
C150.090 (2)0.097 (3)0.075 (2)0.017 (2)0.0348 (18)0.024 (2)
C140.0841 (19)0.070 (2)0.0478 (15)0.019 (2)0.0218 (13)0.0020 (16)
C190.0637 (16)0.066 (2)0.0557 (16)0.0106 (17)0.0162 (13)0.0225 (17)
O10.0397 (8)0.0571 (13)0.0423 (9)0.0071 (9)0.0115 (6)0.0039 (8)
N20.0418 (10)0.0513 (15)0.0371 (10)0.0040 (11)0.0107 (8)0.0025 (10)
O20.0621 (11)0.0616 (14)0.0337 (9)0.0215 (10)0.0174 (7)0.0054 (9)
Geometric parameters (Å, º) top
C5—N21.273 (3)C12—H12A0.9600
C5—C131.473 (3)C12—H12B0.9600
C5—C61.492 (3)C12—H12C0.9600
C6—C21.540 (3)C11—H11A0.9600
C6—C71.545 (4)C11—H11B0.9600
C6—H60.9800C11—H11C0.9600
C7—C81.534 (5)C13—C141.380 (5)
C7—C101.552 (4)C13—C181.390 (4)
C7—H70.9800C18—C171.391 (4)
C8—C91.532 (4)C18—H180.9300
C8—H8A0.9700C17—C161.348 (6)
C8—H8B0.9700C17—H170.9300
C9—C11.545 (4)C16—C151.374 (6)
C9—H9A0.9700C16—H160.9300
C9—H9B0.9700C15—C141.390 (4)
C1—C191.522 (4)C15—H150.9300
C1—C21.547 (3)C14—H140.9300
C1—C101.558 (4)C19—H19A0.9600
C2—O21.384 (3)C19—H19B0.9600
C2—O11.465 (3)C19—H19C0.9600
C10—C111.532 (5)O1—N21.411 (3)
C10—C121.548 (4)O2—H20.8200
N2—C5—C13121.6 (2)C11—C10—C1116.2 (2)
N2—C5—C6113.7 (2)C12—C10—C1113.8 (3)
C13—C5—C6124.6 (2)C7—C10—C193.18 (19)
C5—C6—C2102.15 (19)C10—C12—H12A109.5
C5—C6—C7115.5 (2)C10—C12—H12B109.5
C2—C6—C7102.88 (19)H12A—C12—H12B109.5
C5—C6—H6111.8C10—C12—H12C109.5
C2—C6—H6111.8H12A—C12—H12C109.5
C7—C6—H6111.8H12B—C12—H12C109.5
C8—C7—C6108.5 (2)C10—C11—H11A109.5
C8—C7—C10102.5 (3)C10—C11—H11B109.5
C6—C7—C10101.8 (2)H11A—C11—H11B109.5
C8—C7—H7114.2C10—C11—H11C109.5
C6—C7—H7114.2H11A—C11—H11C109.5
C10—C7—H7114.2H11B—C11—H11C109.5
C9—C8—C7102.6 (2)C14—C13—C18118.5 (3)
C9—C8—H8A111.2C14—C13—C5120.2 (2)
C7—C8—H8A111.2C18—C13—C5121.3 (3)
C9—C8—H8B111.2C17—C18—C13120.0 (3)
C7—C8—H8B111.2C17—C18—H18120.0
H8A—C8—H8B109.2C13—C18—H18120.0
C8—C9—C1104.7 (3)C16—C17—C18121.0 (3)
C8—C9—H9A110.8C16—C17—H17119.5
C1—C9—H9A110.8C18—C17—H17119.5
C8—C9—H9B110.8C17—C16—C15119.9 (3)
C1—C9—H9B110.8C17—C16—H16120.1
H9A—C9—H9B108.9C15—C16—H16120.1
C19—C1—C9113.9 (3)C16—C15—C14120.2 (4)
C19—C1—C2114.5 (2)C16—C15—H15119.9
C9—C1—C2106.7 (2)C14—C15—H15119.9
C19—C1—C10117.8 (2)C13—C14—C15120.4 (3)
C9—C1—C10101.4 (2)C13—C14—H14119.8
C2—C1—C10100.9 (2)C15—C14—H14119.8
O2—C2—O1107.27 (17)C1—C19—H19A109.5
O2—C2—C6118.0 (2)C1—C19—H19B109.5
O1—C2—C6103.82 (17)H19A—C19—H19B109.5
O2—C2—C1110.61 (19)C1—C19—H19C109.5
O1—C2—C1113.1 (2)H19A—C19—H19C109.5
C6—C2—C1104.03 (18)H19B—C19—H19C109.5
C11—C10—C12106.6 (3)N2—O1—C2109.86 (17)
C11—C10—C7113.8 (3)C5—N2—O1110.33 (18)
C12—C10—C7113.2 (2)C2—O2—H2109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···N2i0.822.062.877 (3)174
Symmetry code: (i) x+3/2, y+1/2, z.

Experimental details

Crystal data
Chemical formulaC17H21NO2
Mr271.35
Crystal system, space groupMonoclinic, C2
Temperature (K)296
a, b, c (Å)22.1681 (18), 6.6134 (5), 10.7358 (8)
β (°) 108.277 (3)
V3)1494.5 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.58 × 0.34 × 0.14
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2008)
Tmin, Tmax0.627, 0.745
No. of measured, independent and
observed [I > 2σ(I)] reflections
4379, 1350, 1220
Rint0.025
(sin θ/λ)max1)0.584
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.106, 1.08
No. of reflections1350
No. of parameters186
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.29, 0.24

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012)and PLATON (Spek, 2009), WinGX (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···N2i0.822.062.877 (3)174
Symmetry code: (i) x+3/2, y+1/2, z.
 

Acknowledgements

The authors thank Professor Daniel Avignant for the X-ray measurements.

References

First citationAit Ali, M., Karim, A., Castanet, Y., Mortreux, A. & Mentré, O. (2006). Acta Cryst. E62, m3160–m3162.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
First citationBruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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