1,2,3,4,4a,12a-Hexa­hydro-2,5,5-tri­methyl-1H-[2]­benzo­pyrano­[3,2-c]­coumarin

The di­hydro­pyran ring in the title compound, C₁₉H₂₂O₃, adopts a half-chair conformation and the cyclo­hexane ring is in a chair conformation. In addition to van der Waals interactions, the molecular packing in the crystal is stabilized by C—H...π interactions, involving the dihydropyran ring of the symmetry-related mol­ecules.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.042
• wR factor = 0.114
• Data-to-parameter ratio = 11.3

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

General Notes



REFLT_03
         From the CIF: _diffrn_reflns_theta_max           28.30
         From the CIF: _reflns_number_total               2247
         Count of symmetry unique reflns         2253
         Completeness (_total/calc)             99.73%
         TEST3: Check Friedels for noncentro structure
         Estimate of Friedel pairs measured         0
         Fraction of Friedel pairs measured     0.000
         Are heavy atom types Z>Si present           no
          Please check that the estimate of the number of Friedel pairs is
          correct. If it is not, please give the correct count in the
          _publ_section_exptl_refinement section of the submitted CIF.

---

S1. Comment

Coumarin derivatives possess a variety of biological activities (Crombic et al., 1985). They are used in oral anticoagulation therapy (Cole et al., 1988; Greenfield, 1988) and in enzyme determination (Michel & Durant, 1976). Coumarin derivatives exhibit solid-state photochemical reactions (Gnanaguru et al., 1985). Some amino- and hydroxycoumarin derivatives are used as laser dyes (Masilamani, 1979). As part of our studies on these derivatives, the X-ray structure determination of the title compound, (I), was undertaken.

The title molecule (Fig. 1) contains a fused four-ring system A/B/C/D. The geometry of the coumarin ring system (Table 1) is comparable to that observed in other coumarin derivatives (Chinnakali et al., 1998, 1999; Krishna et al., 2003). The bond lengths in the dihydropyran ring (C) and cyclohexane ring (D) have normal values (Allen et al., 1987). In the coumarin moiety, the pyran ring is planar within ±0.056 (2) Å and the dihedral angle between the weighted least-squares planes through the benzene and pyran rings is 3.55 (6)°. The dihydropyran ring adopts a half-chair conformation with asymmetry parameter ΔC₂(C12—C17) equal to 0.004 (1) (Nardelli, 1983). The cyclohexane ring (D) adopts a chair conformation and the methyl group is equatorially attached to it. The C/D ring junction is trans. An intramolecular C—H···O hydrogen bond involving the carbonyl O atom is observed. The pyran ring of the symmetry-related molecules at (1/2 + x, 3/2 − y, −z) are involved in C—H···π interactions. In Table 2, Cg denotes the centroid of the pyran ring.

S2. Experimental

To a refluxing solution of 4-hydroxycoumarin (1 mmol) in 10 ml of dry ethanol, citranellal (1 mmol) was added and the reaction mixture was refluxed for 4 h. Evaporation of the solvent under rotor evaporator followed by flash silica-gel chromatography yielded the title compound. The compound was recrystallized from methanol/chloroform (1:1) by slow evaporation.

S3. Refinement

H atoms were positioned geometrically and were treated as riding on their parent C atoms, with aromatic C—H distances of 0.93 Å, methyl C—H distances of 0.96 Å, methylene C—H distances of 0.98 Å and ethylene C—H distances of 0.97 Å. Due to the lack of anomalous scatterers, the absolute configuration was not determined from the X-ray diffraction data and the Friedel pairs were merged. The absolute configuration is unknown.

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 1990); software used to prepare material for publication: SHELXL97 and PARST (Nardelli, 1995).

Figures

Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids.

1,2,3,4,4a,12a-Hexahydro-2,5,5-trimethyl-1-H-[2]benzopyrano[3,2-c]coumarin

Crystal data

C19H22O3	F(000) = 640
Mr = 298.37	Dx = 1.248 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 6654 reflections
a = 8.8291 (4) Å	θ = 2.9–27.6°
b = 9.8819 (4) Å	µ = 0.08 mm^−1
c = 18.2053 (8) Å	T = 293 K
V = 1588.38 (12) Å^3	Block, colourless
Z = 4	0.50 × 0.16 × 0.14 mm

Data collection

Siemens SMART CCD area-detector diffractometer	1960 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.034
Graphite monochromator	θmax = 28.3°, θmin = 2.2°
ω scans	h = −11→11
11019 measured reflections	k = −12→13
2247 independent reflections	l = −22→24

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.114	H-atom parameters constrained
S = 1.09	w = 1/[σ^2(Fo^2) + (0.0647P)^2 + 0.1224P] where P = (Fo^2 + 2Fc^2)/3
2247 reflections	(Δ/σ)max < 0.001
199 parameters	Δρmax = 0.21 e Å^−3
0 restraints	Δρmin = −0.21 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	−0.00640 (19)	0.52266 (13)	0.05327 (8)	0.0488 (4)
C2	0.0105 (2)	0.60381 (19)	−0.00866 (11)	0.0439 (4)
C3	−0.0244 (2)	0.74706 (19)	−0.00197 (11)	0.0376 (4)
C4	−0.0555 (2)	0.79865 (18)	0.06553 (10)	0.0365 (4)
C5	−0.1327 (2)	0.7583 (2)	0.19655 (11)	0.0450 (4)
H5	−0.1502	0.8501	0.2037	0.054*
C6	−0.1573 (3)	0.6683 (2)	0.25310 (11)	0.0525 (5)
H6	−0.1910	0.6997	0.2984	0.063*
C7	−0.1322 (3)	0.5311 (2)	0.24278 (12)	0.0574 (6)
H7	−0.1493	0.4710	0.2812	0.069*
C8	−0.0819 (3)	0.4831 (2)	0.17590 (13)	0.0533 (5)
H8	−0.0646	0.3911	0.1691	0.064*
C9	−0.0576 (2)	0.57364 (18)	0.11901 (11)	0.0412 (4)
C10	−0.0815 (2)	0.71163 (18)	0.12851 (10)	0.0375 (4)
O11	−0.06667 (18)	0.93083 (12)	0.08116 (7)	0.0424 (3)
C12	−0.0135 (3)	1.0277 (2)	0.02525 (11)	0.0431 (4)
C13	−0.0403 (3)	1.0758 (2)	−0.11316 (12)	0.0534 (5)
H13A	−0.0747	1.1661	−0.1007	0.064*
H13B	0.0678	1.0795	−0.1224	0.064*
C14	−0.1227 (3)	1.0261 (2)	−0.18192 (12)	0.0549 (5)
H14A	−0.2310	1.0336	−0.1741	0.066*
H14B	−0.0962	1.0843	−0.2228	0.066*
C15	−0.0848 (3)	0.8803 (3)	−0.20200 (11)	0.0510 (5)
H15	0.0219	0.8772	−0.2167	0.061*
C16	−0.1047 (3)	0.7858 (2)	−0.13570 (10)	0.0450 (4)
H16A	−0.2112	0.7802	−0.1230	0.054*
H16B	−0.0703	0.6957	−0.1486	0.054*
C17	−0.0724 (2)	0.97919 (18)	−0.04916 (10)	0.0391 (4)
H17	−0.1828	0.9726	−0.0448	0.047*
C18	−0.0148 (2)	0.83683 (18)	−0.06908 (10)	0.0391 (4)
H18	0.0919	0.8442	−0.0834	0.047*
C19	0.1581 (3)	1.0321 (3)	0.03032 (14)	0.0574 (6)
H19A	0.1992	0.9471	0.0144	0.086*
H19B	0.1876	1.0487	0.0803	0.086*
H19C	0.1960	1.1034	−0.0005	0.086*
C20	−0.0868 (4)	1.15905 (19)	0.04955 (12)	0.0614 (7)
H20A	−0.1948	1.1513	0.0455	0.092*
H20B	−0.0519	1.2317	0.0189	0.092*
H20C	−0.0600	1.1773	0.0997	0.092*
C21	−0.1797 (4)	0.8333 (3)	−0.26730 (13)	0.0694 (7)
H21A	−0.1539	0.7415	−0.2792	0.104*
H21B	−0.1596	0.8903	−0.3088	0.104*
H21C	−0.2852	0.8384	−0.2549	0.104*
O22	0.0572 (2)	0.54743 (16)	−0.06247 (9)	0.0633 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0633 (9)	0.0320 (6)	0.0512 (8)	0.0088 (7)	−0.0048 (7)	−0.0023 (6)
C2	0.0466 (10)	0.0374 (9)	0.0476 (10)	0.0076 (8)	−0.0018 (9)	−0.0046 (8)
C3	0.0376 (8)	0.0331 (8)	0.0420 (9)	0.0024 (7)	−0.0014 (7)	−0.0008 (7)
C4	0.0352 (9)	0.0308 (7)	0.0436 (9)	−0.0003 (7)	−0.0024 (7)	−0.0006 (7)
C5	0.0538 (11)	0.0378 (9)	0.0435 (10)	−0.0004 (9)	−0.0003 (9)	−0.0002 (8)
C6	0.0628 (13)	0.0531 (12)	0.0415 (10)	0.0005 (11)	0.0006 (10)	0.0048 (9)
C7	0.0735 (15)	0.0482 (11)	0.0507 (12)	−0.0043 (12)	−0.0060 (11)	0.0163 (10)
C8	0.0677 (14)	0.0333 (9)	0.0589 (12)	0.0010 (10)	−0.0104 (11)	0.0069 (9)
C9	0.0443 (10)	0.0349 (8)	0.0445 (9)	0.0012 (8)	−0.0085 (8)	−0.0004 (8)
C10	0.0379 (9)	0.0336 (8)	0.0410 (9)	−0.0006 (8)	−0.0051 (7)	0.0013 (7)
O11	0.0577 (8)	0.0294 (6)	0.0402 (6)	−0.0011 (6)	0.0053 (6)	−0.0019 (5)
C12	0.0570 (11)	0.0300 (8)	0.0422 (9)	−0.0039 (9)	0.0027 (8)	0.0012 (8)
C13	0.0678 (14)	0.0432 (10)	0.0492 (11)	−0.0056 (11)	−0.0019 (10)	0.0102 (9)
C14	0.0623 (14)	0.0575 (12)	0.0451 (10)	0.0008 (11)	−0.0047 (10)	0.0131 (10)
C15	0.0497 (11)	0.0644 (12)	0.0390 (9)	0.0035 (11)	0.0014 (9)	0.0030 (9)
C16	0.0490 (11)	0.0460 (10)	0.0400 (9)	0.0017 (9)	−0.0008 (8)	−0.0031 (8)
C17	0.0426 (9)	0.0346 (8)	0.0402 (9)	0.0014 (8)	0.0020 (8)	0.0031 (7)
C18	0.0394 (9)	0.0384 (9)	0.0393 (9)	0.0018 (8)	0.0025 (7)	−0.0007 (7)
C19	0.0576 (13)	0.0562 (13)	0.0583 (12)	−0.0167 (12)	−0.0043 (10)	−0.0018 (11)
C20	0.0972 (19)	0.0320 (9)	0.0549 (12)	0.0043 (11)	0.0071 (13)	−0.0029 (9)
C21	0.0864 (18)	0.0792 (17)	0.0425 (11)	0.0029 (16)	−0.0098 (12)	−0.0040 (12)
O22	0.0837 (13)	0.0503 (8)	0.0560 (9)	0.0241 (9)	0.0054 (8)	−0.0095 (7)

Geometric parameters (Å, º)

O1—C9	1.375 (2)	C13—H13A	0.97
O1—C2	1.392 (2)	C13—H13B	0.97
C2—O22	1.200 (2)	C14—C15	1.523 (4)
C2—C3	1.454 (3)	C14—H14A	0.97
C3—C4	1.358 (3)	C14—H14B	0.97
C3—C18	1.512 (3)	C15—C21	1.527 (3)
C4—O11	1.340 (2)	C15—C16	1.536 (3)
C4—C10	1.452 (3)	C15—H15	0.98
C5—C6	1.377 (3)	C16—C18	1.534 (3)
C5—C10	1.397 (3)	C16—H16A	0.97
C5—H5	0.93	C16—H16B	0.97
C6—C7	1.387 (3)	C17—C18	1.539 (2)
C6—H6	0.93	C17—H17	0.98
C7—C8	1.380 (3)	C18—H18	0.98
C7—H7	0.93	C19—H19A	0.96
C8—C9	1.385 (3)	C19—H19B	0.96
C8—H8	0.93	C19—H19C	0.96
C9—C10	1.391 (3)	C20—H20A	0.96
O11—C12	1.474 (2)	C20—H20B	0.96
C12—C20	1.516 (3)	C20—H20C	0.96
C12—C19	1.518 (3)	C21—H21A	0.96
C12—C17	1.528 (3)	C21—H21B	0.96
C13—C14	1.528 (3)	C21—H21C	0.96
C13—C17	1.532 (3)
C9—O1—C2	122.0 (1)	C13—C14—H14B	108.9
O22—C2—O1	115.51 (17)	H14A—C14—H14B	107.7
O22—C2—C3	126.39 (19)	C14—C15—C21	110.8 (2)
O1—C2—C3	118.06 (17)	C14—C15—C16	111.19 (17)
C4—C3—C2	118.95 (18)	C21—C15—C16	111.4 (2)
C4—C3—C18	121.47 (16)	C14—C15—H15	107.8
C2—C3—C18	119.44 (17)	C21—C15—H15	107.8
O11—C4—C3	124.93 (17)	C16—C15—H15	107.8
O11—C4—C10	113.45 (16)	C18—C16—C15	111.24 (17)
C3—C4—C10	121.61 (16)	C18—C16—H16A	109.4
C6—C5—C10	120.06 (18)	C15—C16—H16A	109.4
C6—C5—H5	120.0	C18—C16—H16B	109.4
C10—C5—H5	120.0	C15—C16—H16B	109.4
C5—C6—C7	120.3 (2)	H16A—C16—H16B	108.0
C5—C6—H6	119.8	C12—C17—C13	114.57 (16)
C7—C6—H6	119.8	C12—C17—C18	112.54 (16)
C8—C7—C6	120.5 (2)	C13—C17—C18	109.20 (15)
C8—C7—H7	119.8	C12—C17—H17	106.7
C6—C7—H7	119.8	C13—C17—H17	106.7
C7—C8—C9	119.18 (18)	C18—C17—H17	106.7
C7—C8—H8	120.4	C3—C18—C16	114.62 (16)
C9—C8—H8	120.4	C3—C18—C17	109.10 (15)
O1—C9—C8	117.71 (17)	C16—C18—C17	108.41 (16)
O1—C9—C10	121.15 (18)	C3—C18—H18	108.2
C8—C9—C10	121.12 (19)	C16—C18—H18	108.2
C9—C10—C5	118.87 (18)	C17—C18—H18	108.2
C9—C10—C4	117.31 (18)	C12—C19—H19A	109.5
C5—C10—C4	123.80 (17)	C12—C19—H19B	109.5
C4—O11—C12	117.6 (2)	H19A—C19—H19B	109.5
O11—C12—C20	102.63 (16)	C12—C19—H19C	109.5
O11—C12—C19	107.11 (18)	H19A—C19—H19C	109.5
C20—C12—C19	112.6 (2)	H19B—C19—H19C	109.5
O11—C12—C17	107.45 (15)	C12—C20—H20A	109.5
C20—C12—C17	112.47 (19)	C12—C20—H20B	109.5
C19—C12—C17	113.73 (19)	H20A—C20—H20B	109.5
C14—C13—C17	109.57 (18)	C12—C20—H20C	109.5
C14—C13—H13A	109.8	H20A—C20—H20C	109.5
C17—C13—H13A	109.8	H20B—C20—H20C	109.5
C14—C13—H13B	109.8	C15—C21—H21A	109.5
C17—C13—H13B	109.8	C15—C21—H21B	109.5
H13A—C13—H13B	108.2	H21A—C21—H21B	109.5
C15—C14—C13	113.32 (19)	C15—C21—H21C	109.5
C15—C14—H14A	108.9	H21A—C21—H21C	109.5
C13—C14—H14A	108.9	H21B—C21—H21C	109.5
C15—C14—H14B	108.9
C9—O1—C2—O22	179.48 (19)	C10—C4—O11—C12	168.33 (16)
C9—O1—C2—C3	1.4 (3)	C4—O11—C12—C20	162.8 (2)
O22—C2—C3—C4	−170.6 (2)	C4—O11—C12—C19	−78.5 (2)
O1—C2—C3—C4	7.3 (3)	C4—O11—C12—C17	44.1 (2)
O22—C2—C3—C18	5.2 (3)	C17—C13—C14—C15	−54.8 (3)
O1—C2—C3—C18	−176.98 (16)	C13—C14—C15—C21	175.5 (2)
C2—C3—C4—O11	169.35 (19)	C13—C14—C15—C16	51.1 (3)
C18—C3—C4—O11	−6.3 (3)	C14—C15—C16—C18	−53.4 (3)
C2—C3—C4—C10	−11.3 (3)	C21—C15—C16—C18	−177.5 (2)
C18—C3—C4—C10	173.03 (17)	O11—C12—C17—C13	174.47 (17)
C10—C5—C6—C7	−0.3 (4)	C20—C12—C17—C13	62.3 (2)
C5—C6—C7—C8	0.1 (4)	C19—C12—C17—C13	−67.2 (2)
C6—C7—C8—C9	−0.3 (4)	O11—C12—C17—C18	−60.0 (2)
C2—O1—C9—C8	175.09 (19)	C20—C12—C17—C18	−172.19 (18)
C2—O1—C9—C10	−6.1 (3)	C19—C12—C17—C18	58.4 (2)
C7—C8—C9—O1	179.5 (2)	C14—C13—C17—C12	−172.33 (19)
C7—C8—C9—C10	0.7 (3)	C14—C13—C17—C18	60.4 (2)
O1—C9—C10—C5	−179.61 (17)	C4—C3—C18—C16	−131.78 (19)
C8—C9—C10—C5	−0.8 (3)	C2—C3—C18—C16	52.6 (2)
O1—C9—C10—C4	2.2 (3)	C4—C3—C18—C17	−10.0 (2)
C8—C9—C10—C4	−179.04 (19)	C2—C3—C18—C17	174.32 (18)
C6—C5—C10—C9	0.7 (3)	C15—C16—C18—C3	−178.25 (17)
C6—C5—C10—C4	178.7 (2)	C15—C16—C18—C17	59.6 (2)
O11—C4—C10—C9	−173.90 (17)	C12—C17—C18—C3	43.0 (2)
C3—C4—C10—C9	6.7 (3)	C13—C17—C18—C3	171.40 (16)
O11—C4—C10—C5	8.0 (3)	C12—C17—C18—C16	168.44 (16)
C3—C4—C10—C5	−171.41 (19)	C13—C17—C18—C16	−63.2 (2)
C3—C4—O11—C12	−12.3 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C16—H16B···O22	0.97	2.42	3.061 (3)	123
C19—H19A···Cg^i	0.96	2.90	3.681 (3)	140

Symmetry code: (i) x+1/2, −y+3/2, −z.