(±)-(3aR,4R,4aS)-4-Phenyl-3,3a,4,4a-tetra­hydro-1H-cyclo­propa­[c]­furan-1-one

The furan­one ring in the title compound, C₁₁H₁₀O₂, is effectively planar and forms a dihedral angle of 74.42 (14)° with the cyclo­propyl ring. The phenyl ring is somewhat twisted with respect to the approximate `mirror plane' of the bicyclic system; the dihedral angles formed by the plane of the phenyl ring with the cyclo­propyl and furan­one mean planes are almost equal, viz. 98.30 (14) and 98.14 (10)°, respectively.

Key indicators

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.039
• wR factor = 0.144
• Data-to-parameter ratio = 16.6

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



ABSMU_01  Alert C The ratio of given/expected absorption coefficient lies
          outside the range 0.99 <> 1.01
          Calculated value of mu =     0.092
          Value of mu given      =     0.090


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 1 Alert Level C = Please check

---

S1. Comment

The title compound, (I), was prepared by the cyclization of 2-(hydroxymethyl)-3-phenylcyclopropane-1-carboxylic acid (Avery et al., 2001). An enantiomerically pure form of the compound has been reported previously (Doyle et al., 1995); the structure of the racemic crystal was determined in the present work (a view of the molecule with the atomic numbering is given in Fig. 1).

The deviations of the O2, C1, C3, C3a and C4a atoms from their least-squares plane are 0.080 (1), -0.056 (2), -0.068 (2), 0.035 (2) and 0.009 (2) Å, respectively; for reference, the displacement of the C4 atom from this plane is 1.285 (2) Å. The dihedral angle formed by the five-membered ring and the plane through the cyclopropyl ring is 74.42 (14)°. The phenyl ring is somewhat twisted with respect to the approximate `mirror plane' of the bicyclic system; the dihedral angles formed by the plane of the phenyl ring with the cyclopropyl and furanone mean planes are, quite expectedly, almost equal [98.30 (14) and 98.14 (10)°, respectively], and the C4a—C4—C41—C42 torsion angle is 152.59 (17)°. The twist about the C4—C41 bond presumably allows for the minimization of the total energy associated with short intramolecular H···H contacts involving H atoms at the C4, C3a, C4a, C42 and C46 atoms.

S2. Experimental

The title compound was prepared by the trifluoroacetic acid-catalysed cyclization of the 2-(hydroxymethyl)-3-phenylcyclopropane-1-carboxylic acid precursor as described previously (Avery et al., 2001). Crystals were obtained from the slow evaporation of a heptane solution of the compound; m.p. 367–369 K.

S3. Refinement

H atoms were placed in geometrically calculated positions and included in the final refinement in the riding model approximation with an overall displacement parameter.

Computing details

Data collection: MSC/AFC Diffractometer Control Software (Molecular Structure Corporation, 1996); cell refinement: MSC/AFC Diffractometer Control Software; data reduction: TEXSAN for Windows (Molecular Structure Corporation, 1997); program(s) used to solve structure: SIR97 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); software used to prepare material for publication: SHELXL97.

Figures

Fig. 1. The molecular structure and crystallographic numbering scheme for (I). Displacement ellipsoids are shown at the 50% probability level (Johnson, 1976).

(I)

Crystal data

C11H10O2	F(000) = 368
Mr = 174.20	Dx = 1.348 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
a = 8.927 (1) Å	Cell parameters from 25 reflections
b = 10.2311 (9) Å	θ = 7.4–12.9°
c = 9.776 (2) Å	µ = 0.09 mm^−1
β = 106.04 (2)°	T = 173 K
V = 858.1 (2) Å^3	Plate, pale yellow
Z = 4	0.45 × 0.39 × 0.07 mm

Data collection

Rigaku AFC-7R diffractometer	Rint = 0.023
Radiation source: Rotating anode	θmax = 27.5°, θmin = 3.1°
Graphite monochromator	h = 0→11
ω–2θ scans	k = 0→13
2215 measured reflections	l = −12→12
1975 independent reflections	3 standard reflections every 400 reflections
1205 reflections with I > 2σ(I)	intensity decay: 0.8%

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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.144	H-atom parameters constrained
S = 0.93	w = 1/[σ^2(Fo^2) + (0.1P)^2] where P = (Fo^2 + 2Fc^2)/3
1975 reflections	(Δ/σ)max < 0.001
119 parameters	Δρmax = 0.23 e Å^−3
0 restraints	Δρmin = −0.23 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	0.81985 (16)	0.47550 (14)	−0.22703 (15)	0.0411 (4)
O2	0.89696 (15)	0.28110 (13)	−0.28633 (12)	0.0327 (3)
C1	0.8786 (2)	0.37053 (17)	−0.18989 (19)	0.0283 (4)
C3a	1.0161 (2)	0.18976 (17)	−0.05885 (17)	0.0260 (4)
H3C	1.1146	0.1635	0.0133	0.0393 (18)*
C3	1.0011 (2)	0.17653 (18)	−0.21628 (18)	0.0314 (4)
H3A	1.1043	0.1857	−0.2346	0.0393 (18)*
H3B	0.9571	0.0902	−0.2517	0.0393 (18)*
C4a	0.93855 (19)	0.31802 (16)	−0.04488 (18)	0.0261 (4)
H4B	0.9838	0.3776	0.0373	0.0393 (18)*
C4	0.86443 (19)	0.18767 (16)	−0.02229 (17)	0.0250 (4)
H4A	0.7727	0.1610	−0.1021	0.0393 (18)*
C41	0.85289 (19)	0.15267 (16)	0.12207 (18)	0.0253 (4)
C42	0.7339 (2)	0.06979 (18)	0.1345 (2)	0.0299 (4)
H42	0.6623	0.0365	0.0510	0.0393 (18)*
C43	0.7181 (2)	0.03500 (19)	0.2671 (2)	0.0357 (4)
H43	0.6372	−0.0229	0.2736	0.0393 (18)*
C44	0.8196 (3)	0.0842 (2)	0.3895 (2)	0.0394 (5)
H44	0.8074	0.0617	0.4801	0.0393 (18)*
C45	0.9393 (2)	0.1668 (2)	0.3793 (2)	0.0390 (5)
H45	1.0097	0.2005	0.4633	0.0393 (18)*
C46	0.9566 (2)	0.20019 (18)	0.24701 (19)	0.0317 (4)
H46	1.0397	0.2559	0.2411	0.0393 (18)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0450 (8)	0.0320 (7)	0.0474 (8)	0.0114 (6)	0.0146 (6)	0.0153 (6)
O2	0.0397 (7)	0.0331 (7)	0.0240 (6)	0.0031 (6)	0.0065 (5)	0.0021 (5)
C1	0.0275 (8)	0.0262 (9)	0.0317 (9)	−0.0006 (7)	0.0092 (7)	0.0031 (7)
C3a	0.0272 (8)	0.0248 (8)	0.0250 (8)	0.0041 (7)	0.0056 (6)	−0.0005 (6)
C3	0.0403 (10)	0.0263 (9)	0.0287 (9)	0.0052 (8)	0.0113 (8)	−0.0011 (7)
C4a	0.0298 (8)	0.0213 (8)	0.0265 (8)	−0.0001 (7)	0.0065 (7)	−0.0009 (7)
C4	0.0256 (8)	0.0226 (8)	0.0242 (8)	−0.0003 (7)	0.0027 (6)	−0.0001 (7)
C41	0.0271 (8)	0.0210 (8)	0.0274 (8)	0.0042 (6)	0.0072 (7)	0.0011 (6)
C42	0.0292 (9)	0.0268 (9)	0.0343 (10)	0.0035 (7)	0.0094 (7)	0.0008 (7)
C43	0.0353 (10)	0.0304 (10)	0.0478 (11)	0.0052 (8)	0.0222 (8)	0.0086 (8)
C44	0.0524 (12)	0.0399 (11)	0.0325 (10)	0.0113 (10)	0.0226 (9)	0.0085 (8)
C45	0.0475 (12)	0.0400 (11)	0.0268 (9)	0.0062 (9)	0.0056 (8)	0.0001 (8)
C46	0.0325 (9)	0.0322 (9)	0.0285 (9)	−0.0006 (8)	0.0052 (7)	0.0008 (7)

Geometric parameters (Å, º)

O1—C1	1.206 (2)	C4—C41	1.487 (2)
O2—C1	1.356 (2)	C41—C42	1.391 (2)
O2—C3	1.458 (2)	C41—C46	1.400 (2)
C1—C4a	1.471 (2)	C42—C43	1.388 (3)
C3a—C3	1.514 (2)	C43—C44	1.381 (3)
C3a—C4	1.493 (2)	C44—C45	1.387 (3)
C3a—C4a	1.507 (2)	C45—C46	1.387 (3)
C4a—C4	1.532 (2)
C1—O2—C3	110.64 (13)	C41—C4—C3a	122.41 (14)
O1—C1—O2	121.17 (16)	C41—C4—C4a	119.51 (14)
O1—C1—C4a	128.84 (17)	C3a—C4—C4a	59.77 (11)
O2—C1—C4a	109.99 (15)	C42—C41—C46	118.20 (16)
C4—C3a—C4a	61.39 (11)	C42—C41—C4	119.00 (15)
C4—C3a—C3	114.28 (14)	C46—C41—C4	122.80 (15)
C4a—C3a—C3	104.85 (13)	C43—C42—C41	121.00 (17)
O2—C3—C3a	106.10 (14)	C44—C43—C42	120.25 (18)
C1—C4a—C3a	106.52 (14)	C43—C44—C45	119.62 (17)
C1—C4a—C4	113.60 (14)	C44—C45—C46	120.22 (18)
C3a—C4a—C4	58.84 (11)	C45—C46—C41	120.70 (17)