6,6'-oxydichroman.

The title compound, C(18)H(18)O(3), was synthesized from dichroman in concentrated sulfuric acid. The mol-ecule has a twofold axis passing through the central O atom. The dihedral angle between the two symmetry-related benzene rings is 63.6 (3)°. Weak C-H⋯π inter-actions are present in the structure.

Related literature

For related literature, see: Allen et al. (1987 ▶); Li et al. (2006 ▶, 2007 ▶); Xiao, Shi et al. (2007 ▶); Xiao, Xue et al. (2007 ▶); Huang et al. (2007 ▶); Zhang et al. (2007 ▶); Shi et al. (2007 ▶); Cao et al. (2007 ▶); Ruan et al. (2006 ▶).

Experimental

Crystal data

C18H18O3

M = 282.32

Orthorhombic,

a = 17.515 (4) Å

b = 29.660 (6) Å

c = 5.7680 (12) Å

V = 2996.4 (10) Å3

Z = 8

Mo Kα radiation

μ = 0.08 mm−1

T = 298 (2) K

0.23 × 0.20 × 0.20 mm

Data collection

Bruker APEX area-detector diffractometer

Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T min = 0.981, T max = 0.983

4727 measured reflections

855 independent reflections

810 reflections with I > 2σ(I)

R int = 0.073

Refinement

R[F 2 > 2σ(F 2)] = 0.073

wR(F 2) = 0.216

S = 1.13

855 reflections

96 parameters

1 restraint

H-atom parameters constrained

Δρmax = 0.32 e Å−3

Δρmin = −0.55 e Å−3

Data collection: SMART (Siemens, 1996 ▶); cell refinement: SMART; data reduction: SAINT (Siemens, 1996 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a ▶); molecular graphics: SHELXTL (Sheldrick, 1997b ▶); software used to prepare material for publication: SHELXTL.

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536807066779/bq2049sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536807066779/bq2049Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C18H18O3	F000 = 1200
Mr = 282.32	Dx = 1.252 Mg m−3
Orthorhombic, Fdd2	Mo Kα radiation λ = 0.71073 Å
Hall symbol: F 2 -2d	Cell parameters from 872 reflections
a = 17.515 (4) Å	θ = 2.5–24.3º
b = 29.660 (6) Å	µ = 0.08 mm−1
c = 5.7680 (12) Å	T = 298 (2) K
V = 2996.4 (10) Å3	Prism, colorless
Z = 8	0.23 × 0.20 × 0.20 mm

Bruker APEX area-detector diffractometer	855 independent reflections
Radiation source: fine-focus sealed tube	810 reflections with I > 2σ(I)
Monochromator: graphite	Rint = 0.073
T = 298(2) K	θmax = 26.5º
φ and ω scans	θmin = 2.7º
Absorption correction: multi-scan(SADABS; Sheldrick, 1996)	h = −21→21
Tmin = 0.981, Tmax = 0.983	k = −36→32
4727 measured reflections	l = −7→6

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.073	H-atom parameters constrained
wR(F2) = 0.216	w = 1/[σ2(Fo2) + (0.1367P)2 + 4.7011P] where P = (Fo2 + 2Fc2)/3
S = 1.13	(Δ/σ)max < 0.001
855 reflections	Δρmax = 0.32 e Å−3
96 parameters	Δρmin = −0.55 e Å−3
1 restraint	Extinction correction: none
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 631 Friedel pairs

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.

	x	y	z	Uiso*/Ueq
O1	0.5000	0.5000	0.0623 (13)	0.090 (2)
O2	0.7616 (2)	0.44456 (13)	0.5838 (9)	0.0779 (14)
C1	0.6782 (2)	0.43486 (12)	0.2525 (7)	0.0378 (9)
C2	0.6140 (2)	0.44952 (12)	0.1313 (7)	0.0387 (9)
H2	0.6008	0.4345	−0.0045	0.046*
C3	0.5687 (2)	0.48541 (13)	0.2029 (8)	0.0386 (9)
C4	0.5900 (2)	0.50701 (12)	0.4073 (8)	0.0412 (9)
H4	0.5609	0.5310	0.4615	0.049*
C5	0.6539 (2)	0.49345 (13)	0.5317 (8)	0.0413 (9)
H5	0.6670	0.5087	0.6669	0.050*
C6	0.69851 (19)	0.45734 (12)	0.4570 (7)	0.0360 (8)
C7	0.7245 (3)	0.39470 (15)	0.1747 (9)	0.0561 (12)
H7A	0.7590	0.4039	0.0521	0.067*
H7B	0.6904	0.3719	0.1122	0.067*
C8	0.7703 (3)	0.37452 (17)	0.3725 (12)	0.0640 (14)
H8A	0.7361	0.3583	0.4754	0.077*
H8B	0.8067	0.3531	0.3104	0.077*
C9	0.8113 (3)	0.40910 (16)	0.5053 (11)	0.0614 (15)
H9A	0.8355	0.3951	0.6384	0.074*
H9B	0.8511	0.4220	0.4091	0.074*

	U11	U22	U33	U12	U13	U23
O1	0.081 (4)	0.128 (5)	0.060 (4)	0.032 (3)	0.000	0.000
O2	0.074 (2)	0.075 (2)	0.085 (3)	0.0149 (17)	−0.036 (2)	−0.021 (2)
C1	0.0383 (17)	0.0360 (17)	0.039 (2)	0.0011 (13)	−0.0009 (17)	−0.0039 (17)
C2	0.0395 (18)	0.0405 (17)	0.0360 (19)	0.0017 (14)	−0.0002 (17)	−0.0066 (16)
C3	0.0315 (16)	0.0445 (17)	0.040 (2)	0.0029 (13)	0.0022 (16)	0.0016 (17)
C4	0.0379 (18)	0.0384 (17)	0.047 (2)	0.0051 (14)	0.0054 (17)	−0.0053 (18)
C5	0.0408 (19)	0.0434 (19)	0.040 (2)	−0.0047 (15)	−0.0021 (17)	−0.0125 (17)
C6	0.0313 (15)	0.0370 (16)	0.040 (2)	−0.0023 (13)	−0.0014 (16)	0.0013 (16)
C7	0.065 (3)	0.053 (2)	0.051 (3)	0.019 (2)	−0.011 (2)	−0.010 (2)
C8	0.059 (3)	0.057 (2)	0.076 (4)	0.020 (2)	−0.010 (3)	−0.003 (3)
C9	0.048 (2)	0.064 (3)	0.072 (4)	0.0163 (19)	−0.018 (3)	−0.001 (3)

O1—C3i	1.514 (5)	C4—H4	0.9300
O1—C3	1.514 (6)	C5—C6	1.394 (5)
O2—C6	1.379 (5)	C5—H5	0.9300
O2—C9	1.438 (6)	C7—C8	1.518 (7)
C1—C2	1.393 (5)	C7—H7A	0.9700
C1—C6	1.401 (6)	C7—H7B	0.9700
C1—C7	1.509 (5)	C8—C9	1.468 (7)
C2—C3	1.390 (5)	C8—H8A	0.9700
C2—H2	0.9300	C8—H8B	0.9700
C3—C4	1.393 (6)	C9—H9A	0.9700
C4—C5	1.388 (6)	C9—H9B	0.9700
C3i—O1—C3	115.2 (6)	C5—C6—C1	118.9 (3)
C6—O2—C9	121.3 (4)	C1—C7—C8	111.8 (4)
C2—C1—C6	118.6 (3)	C1—C7—H7A	109.3
C2—C1—C7	122.0 (4)	C8—C7—H7A	109.3
C6—C1—C7	119.3 (3)	C1—C7—H7B	109.3
C3—C2—C1	123.4 (4)	C8—C7—H7B	109.3
C3—C2—H2	118.3	H7A—C7—H7B	107.9
C1—C2—H2	118.3	C9—C8—C7	112.1 (4)
C2—C3—C4	116.8 (3)	C9—C8—H8A	109.2
C2—C3—O1	120.9 (4)	C7—C8—H8A	109.2
C4—C3—O1	122.4 (4)	C9—C8—H8B	109.2
C5—C4—C3	121.4 (3)	C7—C8—H8B	109.2
C5—C4—H4	119.3	H8A—C8—H8B	107.9
C3—C4—H4	119.3	O2—C9—C8	112.3 (4)
C4—C5—C6	121.0 (4)	O2—C9—H9A	109.1
C4—C5—H5	119.5	C8—C9—H9A	109.1
C6—C5—H5	119.5	O2—C9—H9B	109.1
O2—C6—C5	119.8 (4)	C8—C9—H9B	109.1
O2—C6—C1	121.3 (3)	H9A—C9—H9B	107.9
C6—C1—C2—C3	−0.1 (6)	C4—C5—C6—O2	−180.0 (4)
C7—C1—C2—C3	177.7 (4)	C4—C5—C6—C1	0.3 (6)
C1—C2—C3—C4	−0.2 (6)	C2—C1—C6—O2	−179.7 (4)
C1—C2—C3—O1	179.4 (3)	C7—C1—C6—O2	2.4 (6)
C3i—O1—C3—C2	142.1 (4)	C2—C1—C6—C5	0.1 (5)
C3i—O1—C3—C4	−38.3 (3)	C7—C1—C6—C5	−177.8 (4)
C2—C3—C4—C5	0.5 (6)	C2—C1—C7—C8	−158.0 (4)
O1—C3—C4—C5	−179.1 (4)	C6—C1—C7—C8	19.9 (6)
C3—C4—C5—C6	−0.6 (6)	C1—C7—C8—C9	−47.3 (6)
C9—O2—C6—C5	−176.6 (4)	C6—O2—C9—C8	−31.5 (7)
C9—O2—C6—C1	3.2 (7)	C7—C8—C9—O2	53.2 (7)

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8b···Cg1ii	0.97	2.906	3.856 (6)	166.49

Table 1

Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the ring C1–C6.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C8—H8B⋯Cg1i	0.97	2.91	3.856 (6)	167

Symmetry code: (i) .