A second triclinic modification of 2',6'-di­methoxy­flavone

Crystals of a second triclinic modification of the title compound, 2-(2,6-di­methoxy­phenyl)-4H-1-benzo­pyran-4-one, C₁₇H₁₄O₄, were grown from a hot cyclo­hexane solution. In the mol­ecule, the O-C-C-C torsion angle at the junction between the benzo­pyran and phenyl rings is 67.6 (3)°.

Computing details

Data collection: CAD-4 EXPRESS (Enraf-Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); software used to prepare material for publication: WinGX (Farrugia, 1998).

2-(2,6-dimethoxyphenyl)-4H-1-benzopyran-4-one

Crystal data

C17H14O4	Z = 2
Mr = 282.28	F(000) = 296
Triclinic, P1	Dx = 1.327 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.721 (2) Å	Cell parameters from 25 reflections
b = 8.905 (5) Å	θ = 2.4–25.9°
c = 11.231 (4) Å	µ = 0.10 mm^−1
α = 97.57 (4)°	T = 293 K
β = 105.69 (3)°	Prism, colourless
γ = 103.60 (3)°	0.42 × 0.40 × 0.05 mm
V = 706.7 (5) Å^3

Data collection

Enraf-Nonius CAD-4 diffractometer	1476 reflections with I > 2σ(I)
Radiation source: Enraf-Nonius FR590	Rint = 0.05
Graphite monochromator	θmax = 30.0°, θmin = 2.4°
non–profiled ω scans	h = −10→10
Absorption correction: ψ scan (North et al., 1968)	k = −12→12
Tmin = 0.907, Tmax = 0.979	l = 0→15
4215 measured reflections	3 standard reflections every 76 reflections
4021 independent reflections	intensity decay: none

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)] = 0.055	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.143	H-atom parameters constrained
S = 0.92	w = 1/[(σ^2(Fo^2) + (0.0566P)^2] where P = [2Fc^2 + max(Fo^2,0)]/3
4021 reflections	(Δ/σ)max = 0.004
192 parameters	Δρmax = 0.13 e Å^−3
0 restraints	Δρmin = −0.16 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. Respect to H atoms, all of them have been calculated.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.3903 (2)	0.13655 (16)	0.38961 (14)	0.0527 (4)
C10	0.5925 (3)	0.3901 (2)	0.3910 (2)	0.0483 (5)
C3	0.3429 (3)	0.2339 (2)	0.2008 (2)	0.0528 (6)
H3	0.2742	0.2179	0.1159	0.063*
C2	0.2990 (3)	0.1228 (2)	0.2653 (2)	0.0470 (5)
C1'	0.1486 (3)	−0.0278 (2)	0.2112 (2)	0.0480 (5)
C9	0.5369 (3)	0.2702 (2)	0.4518 (2)	0.0480 (5)
C4	0.4931 (3)	0.3779 (3)	0.2579 (2)	0.0546 (6)
C5	0.7430 (3)	0.5194 (3)	0.4620 (2)	0.0615 (6)
H5	0.7836	0.6016	0.4237	0.074*
C2'	0.1630 (3)	−0.1396 (3)	0.1183 (2)	0.0560 (6)
O11	0.5341 (3)	0.48088 (18)	0.19920 (15)	0.0837 (6)
C8	0.6257 (3)	0.2768 (3)	0.5772 (2)	0.0634 (6)
H8	0.5863	0.195	0.616	0.076*
O12	0.3234 (2)	−0.10196 (18)	0.08639 (16)	0.0777 (5)
C6'	−0.0116 (3)	−0.0578 (3)	0.2495 (2)	0.0552 (6)
O14	−0.0153 (2)	0.06115 (19)	0.33827 (17)	0.0752 (5)
C6	0.8323 (3)	0.5280 (3)	0.5867 (3)	0.0689 (7)
H6	0.9322	0.6155	0.6328	0.083*
C3'	0.0199 (3)	−0.2799 (3)	0.0652 (2)	0.0637 (7)
H3'	0.0288	−0.3546	0.0027	0.076*
C5'	−0.1522 (3)	−0.1989 (3)	0.1976 (2)	0.0665 (7)
H5'	−0.2575	−0.2203	0.2246	0.08*
C7	0.7731 (4)	0.4057 (3)	0.6437 (2)	0.0733 (7)
H7	0.8343	0.4113	0.7285	0.088*
C4'	−0.1340 (4)	−0.3065 (3)	0.1062 (2)	0.0689 (7)
H4'	−0.2292	−0.4005	0.0708	0.083*
C15	−0.1799 (4)	0.0424 (4)	0.3772 (3)	0.0997 (10)
H15A	−0.2877	0.0259	0.3047	0.15*
H15B	−0.1668	0.1358	0.4364	0.15*
H15C	−0.1955	−0.047	0.4167	0.15*
C13	0.3466 (4)	−0.2108 (4)	−0.0092 (3)	0.1141 (12)
H13A	0.3431	−0.3096	0.0168	0.171*
H13B	0.4651	−0.1689	−0.022	0.171*
H13C	0.2471	−0.2271	−0.0867	0.171*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0564 (9)	0.0485 (9)	0.0589 (10)	0.0138 (8)	0.0249 (8)	0.0179 (7)
C10	0.0436 (12)	0.0441 (12)	0.0636 (15)	0.0142 (10)	0.0262 (12)	0.0094 (11)
C3	0.0554 (14)	0.0551 (14)	0.0497 (13)	0.0101 (12)	0.0232 (11)	0.0127 (11)
C2	0.0503 (13)	0.0477 (13)	0.0513 (14)	0.0173 (11)	0.0261 (11)	0.0112 (10)
C1'	0.0471 (13)	0.0412 (12)	0.0588 (14)	0.0089 (10)	0.0227 (11)	0.0148 (10)
C9	0.0453 (13)	0.0450 (13)	0.0593 (15)	0.0182 (11)	0.0217 (11)	0.0085 (11)
C4	0.0616 (15)	0.0502 (14)	0.0601 (16)	0.0106 (12)	0.0361 (13)	0.0124 (12)
C5	0.0524 (14)	0.0558 (15)	0.0819 (19)	0.0149 (13)	0.0324 (14)	0.0103 (13)
C2'	0.0539 (14)	0.0515 (14)	0.0640 (15)	0.0098 (12)	0.0258 (12)	0.0105 (12)
O11	0.1061 (14)	0.0632 (11)	0.0765 (12)	−0.0065 (10)	0.0414 (11)	0.0246 (9)
C8	0.0663 (17)	0.0645 (16)	0.0641 (17)	0.0282 (14)	0.0162 (14)	0.0200 (13)
O12	0.0748 (12)	0.0631 (10)	0.0962 (13)	0.0059 (9)	0.0518 (10)	−0.0084 (9)
C6'	0.0506 (14)	0.0558 (14)	0.0652 (16)	0.0144 (12)	0.0237 (12)	0.0224 (12)
O14	0.0718 (11)	0.0721 (11)	0.1010 (13)	0.0209 (9)	0.0585 (10)	0.0158 (10)
C6	0.0546 (16)	0.0590 (16)	0.083 (2)	0.0156 (13)	0.0125 (15)	−0.0008 (14)
C3'	0.0668 (16)	0.0524 (15)	0.0643 (16)	0.0087 (13)	0.0175 (14)	0.0079 (12)
C5'	0.0522 (15)	0.0658 (16)	0.0837 (18)	0.0063 (13)	0.0274 (14)	0.0287 (14)
C7	0.0685 (18)	0.0791 (19)	0.0670 (17)	0.0312 (16)	0.0062 (14)	0.0104 (15)
C4'	0.0601 (16)	0.0526 (15)	0.0838 (19)	0.0018 (12)	0.0155 (14)	0.0200 (14)
C15	0.084 (2)	0.120 (2)	0.128 (3)	0.0381 (18)	0.076 (2)	0.031 (2)
C13	0.116 (3)	0.095 (2)	0.128 (3)	0.0052 (19)	0.079 (2)	−0.0305 (19)

Geometric parameters (Å, º)

O1—C2	1.357 (2)	O12—C13	1.426 (3)
O1—C9	1.380 (3)	C6'—O14	1.367 (3)
C10—C9	1.388 (3)	C6'—C5'	1.386 (3)
C10—C5	1.393 (3)	O14—C15	1.433 (3)
C10—C4	1.460 (3)	C6—C7	1.384 (3)
C3—C2	1.335 (3)	C6—H6	0.93
C3—C4	1.443 (3)	C3'—C4'	1.369 (3)
C3—H3	0.93	C3'—H3'	0.93
C2—C1'	1.479 (3)	C5'—C4'	1.369 (3)
C1'—C2'	1.390 (3)	C5'—H5'	0.93
C1'—C6'	1.397 (3)	C7—H7	0.93
C9—C8	1.376 (3)	C4'—H4'	0.93
C4—O11	1.229 (2)	C15—H15A	0.96
C5—C6	1.366 (3)	C15—H15B	0.96
C5—H5	0.93	C15—H15C	0.96
C2'—O12	1.361 (2)	C13—H13A	0.96
C2'—C3'	1.391 (3)	C13—H13B	0.96
C8—C7	1.368 (3)	C13—H13C	0.96
C8—H8	0.93
C2—O1—C9	118.64 (17)	O14—C6'—C1'	114.8 (2)
C9—C10—C5	117.4 (2)	C5'—C6'—C1'	120.3 (2)
C9—C10—C4	119.9 (2)	C6'—O14—C15	117.9 (2)
C5—C10—C4	122.7 (2)	C5—C6—C7	119.6 (2)
C2—C3—C4	122.4 (2)	C5—C6—H6	120.2
C2—C3—H3	118.8	C7—C6—H6	120.2
C4—C3—H3	118.8	C4'—C3'—C2'	119.1 (2)
C3—C2—O1	122.9 (2)	C4'—C3'—H3'	120.5
C3—C2—C1'	124.6 (2)	C2'—C3'—H3'	120.5
O1—C2—C1'	112.43 (18)	C4'—C5'—C6'	119.2 (2)
C2'—C1'—C6'	119.1 (2)	C4'—C5'—H5'	120.4
C2'—C1'—C2	120.11 (19)	C6'—C5'—H5'	120.4
C6'—C1'—C2	120.8 (2)	C8—C7—C6	120.9 (3)
C8—C9—O1	116.1 (2)	C8—C7—H7	119.6
C8—C9—C10	122.0 (2)	C6—C7—H7	119.6
O1—C9—C10	121.9 (2)	C3'—C4'—C5'	122.1 (2)
O11—C4—C3	122.8 (2)	C3'—C4'—H4'	119
O11—C4—C10	123.0 (2)	C5'—C4'—H4'	119
C3—C4—C10	114.18 (19)	O14—C15—H15A	109.5
C6—C5—C10	121.3 (2)	O14—C15—H15B	109.5
C6—C5—H5	119.4	H15A—C15—H15B	109.5
C10—C5—H5	119.4	O14—C15—H15C	109.5
O12—C2'—C1'	115.62 (19)	H15A—C15—H15C	109.5
O12—C2'—C3'	124.1 (2)	H15B—C15—H15C	109.5
C1'—C2'—C3'	120.3 (2)	O12—C13—H13A	109.5
C7—C8—C9	118.9 (2)	O12—C13—H13B	109.5
C7—C8—H8	120.6	H13A—C13—H13B	109.5
C9—C8—H8	120.6	O12—C13—H13C	109.5
C2'—O12—C13	118.58 (19)	H13A—C13—H13C	109.5
O14—C6'—C5'	125.0 (2)	H13B—C13—H13C	109.5