3,4-Dihydr­oxy-9H-xanthen-9-one trihydrate

The xanthone skeleton of the title compound, C₁₃H₈O₄·3H₂O, exhibits a planar conformation, with the hydr­oxy H atoms lying in the plane. In the crystal structure, the mol­ecules are packed into columns with their planar skeletons parallel to one another.

Key indicators

• Single-crystal X-ray study
• T = 291 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.050
• wR factor = 0.151
• Data-to-parameter ratio = 8.8

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT027_ALERT_3_A _diffrn_reflns_theta_full (too) Low ............      24.20 Deg.

Author Response: The crystals were very thin plates which did not diffract very well and therefore reflections could only be measured up to \Qmax=24.20\%.

PLAT029_ALERT_3_A _diffrn_measured_fraction_theta_full Low .......       0.93

Author Response: The crystals were very thin plates which did not diffract very well and therefore reflections could only be measured up to \Qmax=24.20\%.

Alert level C
REFLT03_ALERT_3_C  Reflection count < 95% complete
           From the CIF: _diffrn_reflns_theta_max           24.20
           From the CIF: _diffrn_reflns_theta_full          24.20
           From the CIF: _reflns_number_total               1882
           TEST2: Reflns within _diffrn_reflns_theta_max
           Count of symmetry unique reflns         2032
           Completeness (_total/calc)             92.62%
REFNR01_ALERT_3_C  Ratio of reflections to parameters is < 10 for a
            centrosymmetric structure
            sine(theta)/lambda                0.5768
            Proportion of unique data used    1.0000
            Ratio reflections to parameters   8.8357
THETM01_ALERT_3_C  The value of sine(theta_max)/wavelength is less than 0.590
            Calculated sin(theta_max)/wavelength =    0.5768
PLAT022_ALERT_3_C Ratio Unique / Expected Reflections too Low ....       0.93
PLAT023_ALERT_3_C Resolution (too) Low [sin(th)/Lambda < 0.6].....      24.20 Deg.
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT088_ALERT_3_C Poor Data / Parameter Ratio ....................       8.84
PLAT480_ALERT_4_C Long H...A H-Bond Reported H22W   ..  O4      ..       2.66 Ang.
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          2
              H2 O
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          3
              H2 O
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          4
              H2 O

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

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

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Computing details

Data collection: IPDS1 (Stoe & Cie, 1994); cell refinement: IPDS1; data reduction: IPDS1; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.

3,4-Dihydroxy-9H-xanthen-9-one trihydrate

Crystal data

C13H8O4·3H2O	Z = 2
Mr = 282.24	F(000) = 296
Triclinic, P1	Dx = 1.488 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71069 Å
a = 6.838 (3) Å	Cell parameters from 34 reflections
b = 9.946 (4) Å	θ = 6.5–16.7°
c = 10.087 (4) Å	µ = 0.12 mm^−1
α = 105.94 (5)°	T = 291 K
β = 96.54 (5)°	Parallelepiped, colorless
γ = 103.44 (5)°	0.4 × 0.15 × 0.08 mm
V = 629.9 (5) Å^3

Data collection

Stoe IPDS-1 diffractometer	1270 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.047
Graphite monochromator	θmax = 24.2°, θmin = 3.9°
φ scans	h = −7→7
4054 measured reflections	k = −11→11
1882 independent reflections	l = −11→11

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)] = 0.050	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.151	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0902P)^2 + 0.0203P] where P = (Fo^2 + 2Fc^2)/3
1882 reflections	(Δ/σ)max < 0.001
213 parameters	Δρmax = 0.19 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.

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

	x	y	z	Uiso*/Ueq
O4A	0.2065 (3)	0.90327 (17)	0.14611 (17)	0.0569 (5)
O4	0.1636 (3)	0.65204 (19)	−0.0421 (2)	0.0673 (6)
O9	0.3109 (3)	1.29123 (18)	0.05629 (19)	0.0703 (6)
O3	0.1979 (3)	0.63422 (18)	−0.3166 (2)	0.0679 (6)
C4A	0.2235 (4)	0.9069 (3)	0.0132 (2)	0.0507 (6)
C9A	0.2613 (4)	1.0361 (2)	−0.0224 (2)	0.0497 (6)
C8A	0.2688 (4)	1.1666 (2)	0.2256 (2)	0.0519 (6)
C4	0.2025 (4)	0.7723 (2)	−0.0861 (2)	0.0524 (6)
C2	0.2594 (4)	0.8963 (3)	−0.2602 (3)	0.0564 (7)
H2	0.2726	0.8927	−0.3517	0.068*
C1	0.2801 (4)	1.0271 (3)	−0.1613 (2)	0.0544 (7)
H1	0.3070	1.1117	−0.1869	0.065*
C10A	0.2333 (4)	1.0325 (3)	0.2514 (2)	0.0538 (7)
C3	0.2182 (4)	0.7671 (3)	−0.2234 (2)	0.0537 (7)
C9	0.2823 (4)	1.1736 (3)	0.0844 (2)	0.0525 (7)
C5	0.2221 (5)	1.0225 (3)	0.3850 (3)	0.0656 (8)
H5	0.1992	0.9326	0.4006	0.079*
C8	0.2913 (4)	1.2916 (3)	0.3399 (3)	0.0606 (7)
H8	0.3136	1.3819	0.3253	0.073*
C7	0.2809 (5)	1.2828 (3)	0.4721 (3)	0.0688 (8)
H7	0.2973	1.3664	0.5469	0.083*
C6	0.2453 (5)	1.1462 (3)	0.4934 (3)	0.0719 (9)
H6	0.2373	1.1398	0.5830	0.086*
O1W	0.4180 (4)	1.5930 (3)	0.1866 (2)	0.0857 (7)
O2W	0.1472 (5)	0.3763 (2)	−0.1879 (2)	0.0820 (8)
O3W	0.1913 (5)	0.6550 (3)	−0.5800 (2)	0.0841 (7)
H11W	0.356 (7)	1.623 (5)	0.128 (5)	0.109 (14)*
H12W	0.373 (7)	1.495 (5)	0.142 (5)	0.122 (14)*
H3	0.200 (6)	0.642 (4)	−0.412 (4)	0.097 (11)*
H4	0.163 (7)	0.571 (5)	−0.124 (5)	0.127 (14)*
H31W	0.073 (9)	0.624 (5)	−0.633 (6)	0.14 (2)*
H21W	0.294 (7)	0.386 (4)	−0.176 (4)	0.100 (14)*
H32W	0.270 (8)	0.642 (5)	−0.644 (6)	0.142 (19)*
H22W	0.116 (9)	0.349 (6)	−0.120 (6)	0.16 (2)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O4A	0.0708 (12)	0.0485 (9)	0.0507 (9)	0.0138 (8)	0.0151 (8)	0.0150 (7)
O4	0.0940 (15)	0.0474 (10)	0.0619 (11)	0.0176 (9)	0.0188 (10)	0.0195 (8)
O9	0.0997 (15)	0.0487 (10)	0.0633 (11)	0.0185 (9)	0.0151 (10)	0.0205 (8)
O3	0.0917 (15)	0.0490 (10)	0.0580 (11)	0.0176 (9)	0.0154 (10)	0.0099 (8)
C4A	0.0510 (15)	0.0514 (13)	0.0474 (13)	0.0111 (11)	0.0096 (10)	0.0144 (10)
C9A	0.0498 (15)	0.0457 (13)	0.0522 (13)	0.0122 (11)	0.0086 (11)	0.0142 (10)
C8A	0.0517 (15)	0.0495 (13)	0.0528 (14)	0.0131 (11)	0.0091 (11)	0.0144 (11)
C4	0.0571 (16)	0.0434 (12)	0.0552 (14)	0.0112 (11)	0.0083 (11)	0.0165 (10)
C2	0.0630 (17)	0.0561 (14)	0.0512 (13)	0.0148 (12)	0.0126 (12)	0.0191 (11)
C1	0.0619 (16)	0.0488 (13)	0.0512 (13)	0.0131 (11)	0.0092 (11)	0.0159 (11)
C10A	0.0565 (16)	0.0505 (14)	0.0503 (14)	0.0126 (11)	0.0083 (11)	0.0118 (11)
C3	0.0531 (16)	0.0502 (13)	0.0539 (14)	0.0140 (11)	0.0093 (11)	0.0107 (11)
C9	0.0559 (16)	0.0490 (13)	0.0515 (13)	0.0129 (11)	0.0079 (11)	0.0163 (10)
C5	0.083 (2)	0.0595 (15)	0.0556 (15)	0.0153 (14)	0.0158 (14)	0.0222 (12)
C8	0.0710 (18)	0.0513 (13)	0.0551 (14)	0.0152 (12)	0.0106 (12)	0.0116 (11)
C7	0.084 (2)	0.0617 (16)	0.0541 (15)	0.0197 (14)	0.0132 (14)	0.0074 (12)
C6	0.092 (2)	0.0710 (18)	0.0513 (15)	0.0184 (15)	0.0173 (14)	0.0191 (13)
O1W	0.124 (2)	0.0606 (13)	0.0636 (13)	0.0204 (12)	0.0035 (12)	0.0156 (10)
O2W	0.120 (2)	0.0589 (12)	0.0674 (13)	0.0248 (12)	0.0165 (13)	0.0210 (10)
O3W	0.0938 (19)	0.0874 (15)	0.0601 (13)	0.0213 (13)	0.0105 (13)	0.0102 (11)

Geometric parameters (Å, º)

O4A—C4A	1.369 (3)	C2—H2	0.9300
O4A—C10A	1.382 (3)	C1—H1	0.9300
O4—C4	1.367 (3)	C10A—C5	1.388 (3)
O4—H4	0.98 (5)	C5—C6	1.366 (4)
O9—C9	1.255 (3)	C5—H5	0.9300
O3—C3	1.361 (3)	C8—C7	1.369 (4)
O3—H3	0.99 (4)	C8—H8	0.9300
C4A—C4	1.399 (4)	C7—C6	1.404 (4)
C4A—C9A	1.402 (3)	C7—H7	0.9300
C9A—C1	1.403 (3)	C6—H6	0.9300
C9A—C9	1.455 (4)	O1W—H11W	0.85 (5)
C8A—C10A	1.400 (3)	O1W—H12W	0.92 (5)
C8A—C8	1.408 (4)	O2W—H21W	0.98 (5)
C8A—C9	1.457 (3)	O2W—H22W	0.84 (6)
C4—C3	1.388 (4)	O3W—H31W	0.85 (6)
C2—C1	1.370 (4)	O3W—H32W	0.89 (6)
C2—C3	1.409 (4)
C4A—O4A—C10A	118.98 (19)	C5—C10A—C8A	121.4 (2)
C4—O4—H4	105 (3)	O3—C3—C4	117.1 (2)
C3—O3—H3	110 (2)	O3—C3—C2	122.8 (2)
O4A—C4A—C4	115.5 (2)	C4—C3—C2	120.1 (2)
O4A—C4A—C9A	122.8 (2)	O9—C9—C9A	121.8 (2)
C4—C4A—C9A	121.7 (2)	O9—C9—C8A	122.2 (2)
C4A—C9A—C1	117.9 (2)	C9A—C9—C8A	116.0 (2)
C4A—C9A—C9	119.8 (2)	C6—C5—C10A	119.1 (2)
C1—C9A—C9	122.3 (2)	C6—C5—H5	120.4
C10A—C8A—C8	117.7 (2)	C10A—C5—H5	120.4
C10A—C8A—C9	120.1 (2)	C7—C8—C8A	121.2 (2)
C8—C8A—C9	122.2 (2)	C7—C8—H8	119.4
O4—C4—C3	123.6 (2)	C8A—C8—H8	119.4
O4—C4—C4A	117.5 (2)	C8—C7—C6	119.2 (2)
C3—C4—C4A	118.9 (2)	C8—C7—H7	120.4
C1—C2—C3	120.1 (2)	C6—C7—H7	120.4
C1—C2—H2	119.9	C5—C6—C7	121.3 (2)
C3—C2—H2	119.9	C5—C6—H6	119.4
C2—C1—C9A	121.3 (2)	C7—C6—H6	119.4
C2—C1—H1	119.4	H11W—O1W—H12W	100 (4)
C9A—C1—H1	119.4	H21W—O2W—H22W	102 (5)
O4A—C10A—C5	116.3 (2)	H31W—O3W—H32W	101 (4)
O4A—C10A—C8A	122.2 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O3W	0.99 (4)	1.73 (4)	2.717 (3)	177 (3)
O4—H4···O2W	0.98 (5)	1.84 (5)	2.702 (3)	145 (4)
O1W—H11W···O4^i	0.85 (5)	2.17 (5)	2.999 (4)	168 (4)
O1W—H12W···O9	0.92 (5)	1.89 (5)	2.805 (3)	174 (4)
O2W—H21W···O1W^ii	0.98 (5)	1.95 (5)	2.915 (5)	170 (3)
O2W—H22W···O4^iii	0.84 (6)	2.66 (6)	3.343 (4)	141 (5)
O3W—H31W···O2W^iv	0.85 (6)	2.21 (6)	2.994 (4)	152 (5)
O3W—H32W···O1W^v	0.89 (6)	2.09 (6)	2.968 (4)	172 (5)

Symmetry codes: (i) x, y+1, z; (ii) −x+1, −y+2, −z; (iii) −x, −y+1, −z; (iv) −x, −y+1, −z−1; (v) x, y−1, z−1.