5,2′-Dihydr­oxy-7-methoxy­flavanone

The γ-pyran­one ring of the title mol­ecule, C₁₆H₁₄O₅, adopts an envelope conformation. The crystal packing is stabilized by O—H...O and C—H...O hydrogen bonding.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.064
• wR factor = 0.201
• Data-to-parameter ratio = 12.3

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT027_ALERT_3_B _diffrn_reflns_theta_full (too) Low ............      24.98 Deg.

Alert level C
PLAT026_ALERT_3_C Ratio Observed / Unique Reflections too Low ....         45 Perc.
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C4     -   C4A     ..       5.86 su
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          6

   0 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: CAD-4 Software (Enraf–Nonius, 1994); cell refinement: CAD-4 Software; data reduction: XCAD4 in WinGX (Farrugia, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXL97.

5,2'-Dihydroxy-7-methoxyflavanone

Crystal data

C16H14O5	F(000) = 600
Mr = 286.27	Dx = 1.404 Mg m^−3 Dm = 1.40 Mg m^−3 Dm measured by not measured
Monoclinic, P21/c	Melting point: 200 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 10.1961 (10) Å	Cell parameters from 25 reflections
b = 7.5600 (8) Å	θ = 2–25°
c = 18.243 (2) Å	µ = 0.11 mm^−1
β = 105.59 (2)°	T = 298 K
V = 1354.5 (3) Å^3	Needle, colourless
Z = 4	0.40 × 0.20 × 0.20 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	1066 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.048
Graphite monochromator	θmax = 25.0°, θmin = 2.1°
ω/2θ scans	h = −12→11
Absorption correction: ψ scan (North et al., 1968)	k = 0→8
Tmin = 0.950, Tmax = 0.970	l = −20→21
2475 measured reflections	2 standard reflections every 60 min
2346 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)] = 0.064	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.201	H-atom parameters constrained
S = 0.96	w = 1/[σ^2(Fo^2) + (0.096P)^2] where P = (Fo^2 + 2Fc^2)/3
2346 reflections	(Δ/σ)max = 0.001
190 parameters	Δρmax = 0.21 e Å^−3
0 restraints	Δρmin = −0.27 e Å^−3

Special details

Experimental. The title compound was isolated by Jayaprakasam et al. (1999). and recrystallized by slow evaporation from chloroform.

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	0.7862 (3)	0.8564 (4)	0.11376 (15)	0.0513 (9)
C2	0.7243 (4)	0.8550 (7)	0.1737 (2)	0.0502 (13)
H2	0.6731	0.9659	0.1694	0.060*
C3	0.6215 (5)	0.7099 (6)	0.1675 (2)	0.0531 (13)
H3A	0.6685	0.5975	0.1787	0.064*
H3B	0.5710	0.7291	0.2049	0.064*
C4	0.5239 (4)	0.7019 (6)	0.0897 (2)	0.0398 (10)
O4	0.4078 (3)	0.6378 (4)	0.08009 (16)	0.0520 (9)
C4a	0.5717 (4)	0.7694 (5)	0.0278 (2)	0.0344 (10)
C5	0.4923 (4)	0.7536 (5)	−0.0478 (2)	0.0376 (10)
O5	0.3687 (3)	0.6774 (5)	−0.06541 (17)	0.0561 (9)
H5	0.3502	0.6469	−0.0262	0.084*
C6	0.5448 (4)	0.8175 (6)	−0.1064 (2)	0.0420 (11)
H6	0.4942	0.8057	−0.1568	0.050*
C7	0.6685 (5)	0.8961 (7)	−0.0901 (2)	0.0490 (12)
O7	0.7032 (3)	0.9608 (5)	−0.15116 (16)	0.0638 (10)
C8	0.7512 (4)	0.9108 (7)	−0.0157 (2)	0.0502 (12)
H8	0.8371	0.9623	−0.0052	0.060*
C8a	0.6999 (4)	0.8455 (6)	0.0414 (2)	0.0398 (11)
C9	0.8270 (5)	1.0538 (8)	−0.1396 (3)	0.0742 (16)
H9A	0.8383	1.0916	−0.1877	0.111*
H9B	0.9013	0.9778	−0.1150	0.111*
H9C	0.8259	1.1552	−0.1081	0.111*
C1'	0.8284 (4)	0.8631 (6)	0.2479 (2)	0.0399 (10)
C2'	0.7972 (4)	0.9449 (6)	0.3094 (2)	0.0412 (10)
O2'	0.6685 (3)	1.0117 (4)	0.29596 (16)	0.0570 (9)
H2'	0.6555	1.0456	0.3361	0.086*
C3'	0.8925 (4)	0.9548 (6)	0.3787 (2)	0.0500 (12)
H3'	0.8703	1.0094	0.4194	0.060*
C4'	1.0203 (4)	0.8847 (7)	0.3883 (3)	0.0622 (15)
H4'	1.0841	0.8932	0.4354	0.075*
C5'	1.0551 (4)	0.8014 (7)	0.3286 (3)	0.0568 (13)
H5'	1.1417	0.7543	0.3350	0.068*
C6'	0.9583 (4)	0.7900 (6)	0.2591 (2)	0.0456 (11)
H6'	0.9801	0.7324	0.2189	0.055*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0478 (16)	0.062 (2)	0.0432 (15)	−0.0179 (17)	0.0112 (13)	0.0004 (16)
C2	0.040 (2)	0.070 (4)	0.043 (2)	−0.008 (2)	0.0166 (19)	−0.004 (2)
C3	0.069 (3)	0.046 (3)	0.039 (2)	−0.020 (3)	0.006 (2)	0.006 (2)
C4	0.041 (2)	0.028 (2)	0.049 (2)	−0.003 (2)	0.0082 (19)	−0.003 (2)
O4	0.0464 (16)	0.055 (2)	0.0545 (18)	−0.0102 (17)	0.0137 (14)	−0.0009 (17)
C4a	0.039 (2)	0.025 (2)	0.043 (2)	−0.0086 (19)	0.0163 (17)	−0.0034 (19)
C5	0.045 (2)	0.019 (2)	0.045 (2)	−0.002 (2)	0.0058 (19)	−0.0075 (19)
O5	0.0438 (17)	0.068 (2)	0.0509 (18)	−0.0116 (17)	0.0034 (14)	−0.0069 (16)
C6	0.059 (3)	0.030 (2)	0.036 (2)	0.012 (2)	0.0102 (19)	0.0014 (19)
C7	0.062 (3)	0.048 (3)	0.044 (2)	−0.002 (2)	0.025 (2)	0.003 (2)
O7	0.082 (2)	0.062 (3)	0.0541 (19)	−0.007 (2)	0.0306 (17)	0.0021 (18)
C8	0.058 (2)	0.048 (3)	0.046 (2)	−0.020 (2)	0.016 (2)	0.001 (2)
C8a	0.046 (2)	0.034 (3)	0.039 (2)	−0.005 (2)	0.0109 (18)	0.0003 (19)
C9	0.099 (4)	0.071 (4)	0.067 (3)	−0.020 (4)	0.046 (3)	0.009 (3)
C1'	0.041 (2)	0.041 (3)	0.035 (2)	−0.001 (2)	0.0066 (17)	−0.001 (2)
C2'	0.037 (2)	0.038 (3)	0.049 (2)	0.005 (2)	0.0130 (18)	−0.002 (2)
O2'	0.0500 (17)	0.063 (2)	0.0570 (17)	0.0136 (17)	0.0120 (14)	−0.0047 (17)
C3'	0.058 (3)	0.045 (3)	0.041 (2)	0.003 (3)	0.0038 (19)	−0.015 (2)
C4'	0.052 (3)	0.075 (4)	0.047 (2)	0.011 (3)	−0.009 (2)	−0.008 (3)
C5'	0.041 (2)	0.063 (4)	0.061 (3)	0.010 (3)	0.004 (2)	−0.009 (3)
C6'	0.048 (2)	0.036 (3)	0.052 (2)	0.001 (2)	0.013 (2)	−0.006 (2)

Geometric parameters (Å, º)

O1—C8a	1.377 (4)	O7—C9	1.410 (5)
O1—C2	1.402 (4)	C8—C8a	1.377 (5)
C2—C1'	1.480 (5)	C8—H8	0.93
C2—C3	1.500 (6)	C9—H9A	0.96
C2—H2	0.98	C9—H9B	0.96
C3—C4	1.499 (5)	C9—H9C	0.96
C3—H3A	0.97	C1'—C2'	1.391 (5)
C3—H3B	0.97	C1'—C6'	1.398 (5)
C4—O4	1.248 (5)	C2'—O2'	1.366 (4)
C4—C4a	1.439 (5)	C2'—C3'	1.374 (5)
C4a—C8a	1.388 (5)	O2'—H2'	0.82
C4a—C5	1.404 (5)	C3'—C4'	1.374 (6)
C5—O5	1.344 (4)	C3'—H3'	0.93
C5—C6	1.403 (6)	C4'—C5'	1.385 (6)
O5—H5	0.82	C4'—H4'	0.93
C6—C7	1.353 (6)	C5'—C6'	1.384 (5)
C6—H6	0.93	C5'—H5'	0.93
C7—O7	1.349 (5)	C6'—H6'	0.93
C7—C8	1.396 (6)
C8a—O1—C2	116.2 (3)	C8a—C8—H8	121.5
O1—C2—C1'	110.5 (3)	C7—C8—H8	121.5
O1—C2—C3	113.5 (4)	C8—C8a—O1	115.4 (3)
C1'—C2—C3	114.5 (4)	C8—C8a—C4a	122.9 (4)
O1—C2—H2	105.8	O1—C8a—C4a	121.6 (3)
C1'—C2—H2	105.8	O7—C9—H9A	109.5
C3—C2—H2	105.8	O7—C9—H9B	109.5
C4—C3—C2	111.9 (4)	H9A—C9—H9B	109.5
C4—C3—H3A	109.2	O7—C9—H9C	109.5
C2—C3—H3A	109.2	H9A—C9—H9C	109.5
C4—C3—H3B	109.2	H9B—C9—H9C	109.5
C2—C3—H3B	109.2	C2'—C1'—C6'	118.1 (3)
H3A—C3—H3B	107.9	C2'—C1'—C2	119.5 (4)
O4—C4—C4a	122.4 (4)	C6'—C1'—C2	122.4 (4)
O4—C4—C3	120.8 (4)	O2'—C2'—C3'	123.6 (4)
C4a—C4—C3	116.8 (4)	O2'—C2'—C1'	115.9 (3)
C8a—C4a—C5	118.6 (4)	C3'—C2'—C1'	120.5 (4)
C8a—C4a—C4	120.5 (4)	C2'—O2'—H2'	109.5
C5—C4a—C4	120.9 (4)	C2'—C3'—C4'	120.6 (4)
O5—C5—C6	119.4 (4)	C2'—C3'—H3'	119.7
O5—C5—C4a	121.8 (4)	C4'—C3'—H3'	119.7
C6—C5—C4a	118.8 (4)	C3'—C4'—C5'	120.6 (4)
C5—O5—H5	109.5	C3'—C4'—H4'	119.7
C7—C6—C5	120.4 (4)	C5'—C4'—H4'	119.7
C7—C6—H6	119.8	C6'—C5'—C4'	118.6 (4)
C5—C6—H6	119.8	C6'—C5'—H5'	120.7
O7—C7—C6	114.4 (4)	C4'—C5'—H5'	120.7
O7—C7—C8	123.3 (4)	C5'—C6'—C1'	121.6 (4)
C6—C7—C8	122.2 (4)	C5'—C6'—H6'	119.2
C7—O7—C9	118.7 (4)	C1'—C6'—H6'	119.2
C8a—C8—C7	117.0 (4)
C8a—O1—C2—C1'	178.7 (4)	C7—C8—C8a—C4a	−0.6 (7)
C8a—O1—C2—C3	48.5 (5)	C2—O1—C8a—C8	157.0 (4)
O1—C2—C3—C4	−48.5 (6)	C2—O1—C8a—C4a	−24.6 (6)
C1'—C2—C3—C4	−176.7 (4)	C5—C4a—C8a—C8	1.9 (6)
C2—C3—C4—O4	−154.8 (4)	C4—C4a—C8a—C8	179.4 (4)
C2—C3—C4—C4a	25.9 (6)	C5—C4a—C8a—O1	−176.4 (4)
O4—C4—C4a—C8a	177.6 (4)	C4—C4a—C8a—O1	1.2 (6)
C3—C4—C4a—C8a	−3.1 (6)	O1—C2—C1'—C2'	149.4 (4)
O4—C4—C4a—C5	−4.8 (7)	C3—C2—C1'—C2'	−80.9 (6)
C3—C4—C4a—C5	174.4 (4)	O1—C2—C1'—C6'	−31.0 (6)
C8a—C4a—C5—O5	178.3 (4)	C3—C2—C1'—C6'	98.6 (5)
C4—C4a—C5—O5	0.8 (6)	C6'—C1'—C2'—O2'	−179.0 (4)
C8a—C4a—C5—C6	−0.9 (6)	C2—C1'—C2'—O2'	0.6 (6)
C4—C4a—C5—C6	−178.4 (4)	C6'—C1'—C2'—C3'	0.8 (7)
O5—C5—C6—C7	179.4 (4)	C2—C1'—C2'—C3'	−179.7 (4)
C4a—C5—C6—C7	−1.4 (6)	O2'—C2'—C3'—C4'	180.0 (4)
C5—C6—C7—O7	−176.2 (4)	C1'—C2'—C3'—C4'	0.2 (7)
C5—C6—C7—C8	2.7 (7)	C2'—C3'—C4'—C5'	−0.5 (8)
C6—C7—O7—C9	176.6 (4)	C3'—C4'—C5'—C6'	−0.2 (8)
C8—C7—O7—C9	−2.4 (7)	C4'—C5'—C6'—C1'	1.2 (7)
O7—C7—C8—C8a	177.2 (4)	C2'—C1'—C6'—C5'	−1.5 (7)
C6—C7—C8—C8a	−1.7 (7)	C2—C1'—C6'—C5'	178.9 (5)
C7—C8—C8a—O1	177.8 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2′—H2′···O4^i	0.82	1.94	2.752 (4)	170
O5—H5···O4	0.82	1.87	2.593 (4)	146
C2—H2···O2′	0.98	2.35	2.717 (5)	101
C5′—H5′···O5^ii	0.93	2.58	3.266 (6)	131

Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) x+1, −y+3/2, z+1/2.