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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890

Benzene-1,2,4,5-tetra­carb­­oxy­lic acid bis­­(1,3,7-tri­methyl-2,3,6,7-tetra­hydro-1H-purine-2,6-dione)

aDepartment of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249-0698, USA, and bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: edward.tiekink@gmail.com

(Received 11 August 2013; accepted 11 August 2013; online 17 August 2013)

The asymmetric unit of the title co-crystal, C10H6O8·2C8H10N4O2, comprises a centrosymmetric benzene-1,2,4,5-tetra­carb­oxy­lic acid (LH4) mol­ecule and a mol­ecule of caffeine in a general position. LH4 is nonplanar, with the dihedral angles between the ring and pendent carb­oxy­lic acid groups being 44.22 (7) and 49.74 (7)°. By contrast, the caffeine mol­ecule is planar (r.m.s. deviation = 0.040 Å). Supra­molecular layers parallel to (-1-10) are sustained by carb­oxy­lic acid O—H⋯O(carbon­yl) and O—H⋯N(imidazole) hydrogen bonds, as well as by meth­yl–carbonyl C—H⋯O inter­actions. These stack via ππ inter­actions between the benzene and imidazole rings [inter-centroid distance = 3.4503 (10) Å].

Related literature

For cocrystallization studies with benzene-1,2,4,5-tetra­carb­oxy­lic acid, see: Arman & Tiekink (2013[Arman, H. D. & Tiekink, E. R. T. (2013). Z. Kristallogr. Cryst. Mat. 228, 289-294.]).

[Scheme 1]

Experimental

Crystal data
  • C10H6O8·2C8H10N4O2

  • Mr = 642.55

  • Triclinic, [P \overline 1]

  • a = 7.4570 (15) Å

  • b = 9.0490 (15) Å

  • c = 11.782 (2) Å

  • α = 68.800 (11)°

  • β = 81.124 (13)°

  • γ = 73.441 (9)°

  • V = 709.3 (2) Å3

  • Z = 1

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 98 K

  • 0.55 × 0.30 × 0.25 mm

Data collection
  • Rigaku AFC12 Kappa/SATURN724 diffractometer

  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995[Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.838, Tmax = 1

  • 4935 measured reflections

  • 3213 independent reflections

  • 3006 reflections with I > 2σ(I)

  • Rint = 0.020

  • Standard reflections: 0

Refinement
  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.120

  • S = 1.04

  • 3213 reflections

  • 218 parameters

  • 2 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.37 e Å−3

  • Δρmin = −0.33 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H1O⋯N3i 0.86 (1) 1.83 (1) 2.6774 (17) 171 (2)
O4—H2O⋯O5 0.84 (2) 1.84 (2) 2.6571 (15) 162 (2)
C12—H12B⋯O6ii 0.98 2.30 3.239 (2) 159
Symmetry codes: (i) -x, -y+2, -z+1; (ii) -x+2, -y+1, -z+1.

Data collection: CrystalClear (Molecular Structure Corporation & Rigaku, 2005[Molecular Structure Corporation & Rigaku (2005). CrystalClear. MSC, The Woodlands, Texas, USA, and Rigaku Corporation, Tokyo, Japan.]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEPII (Johnson, 1976[Johnson, C. K. (1976). ORTEPII. Report ORNL-5138. Oak Ridge National Laboratory, Tennessee, USA.]) and DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

The title co-crystal was investigated in continuation of recent structural studies of the products obtained from the co-crystallization of benzene-1,2,4,5-tetracarboxylic acid (LH4) with various pyridyl-containing molecules (Arman & Tiekink, 2013).

The asymmetric unit comprises half a molecule of LH4, being disposed about a centre of inversion, and a molecule of caffeine in a general position, Fig. 1. Twists are evident in LH4 as seen in the dihedral angles of 44.22 (7) and 49.74 (7)° formed, respectively, between the O1- and O3-carboxylic acids and the benzene ring to which they are attached. The 14 non-hydrogen atoms of the caffeine molecule are co-planar with an r.m.s. deviation = 0.040 Å.

In the crystal packing, the HL4 molecule forms two O2—H···O5-carbonyl and two O4—H···N3-imidazole hydrogen bonds to form a supramolecular chain constructed about centrosymmetric 26-membered {···HO—C4OH···OCNCN}2 synthons, Table 1. Chains are connected into a layer approximately parallel to (110) by methyl-C12—H···O6(carbonyl) interactions via centrosymmetric and 10-membered {···OCNCH}2 synthons, Fig. 2. Layers are connected into a three-dimensional architecture by ππ interactions between the benzene and imidazolyl rings [inter-centroid distance = 3.4503 (10) Å, angle of inclination = 9.54 (7)° for symmetry operation x, y, 1 + z], Fig. 3.

Related literature top

For cocrystallization studies with benzene-1,2,4,5-tetracarboxylic acid, see: Arman & Tiekink (2013).

Experimental top

Crystals of (I) were obtained by the co-crystallization of caffeine (Sigma–Aldrich, 0.08 mmol) and benzene-1,2,4,5-tetracarboxylic acid (Sigma–Aldrich, 0.09 mmol) in acetone solution. Crystals were obtained by slow evaporation.

Refinement top

C-bound H atoms were placed in calculated positions (C—H = 0.95–0.98 Å) and were included in the refinement in the riding-model approximation, with Uiso(H) set to 1.2–1.5Ueq(C). The O- and N-bound H atoms were located in a difference Fourier map and were refined with distance restraints of O—H = 0.84 (1) Å and N—H = 0.88 (1) Å, and with Uiso(H) = 1.2Ueq(N) and 1.5Ueq(O).

Computing details top

Data collection: CrystalClear (Molecular Structure Corporation & Rigaku, 2005); cell refinement: CrystalClear (Molecular Structure Corporation & Rigaku, 2005); data reduction: CrystalClear (Molecular Structure Corporation & Rigaku, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. Molecular structures of the components of (I), showing atom-labelling scheme and displacement ellipsoids at the 50% probability level. The unlabelled atoms of HL4 (a) are generated by the symmetry operation 1 - x, 2 - y, 2 - z.
[Figure 2] Fig. 2. Views of the supramolecular layer in (I). The O—H···O (orange), O—H···N (blue) and C—H···O (green) interactions are shown as dashed lines.
[Figure 3] Fig. 3. Unit-cell contents in (I) highlighting the stacking of layers shown in Fig. 2.
Benzene-1,2,4,5-tetracarboxylic acid bis(1,3,7-trimethyl-2,3,6,7-tetrahydro-1H-purine-2,6-dione) top
Crystal data top
C10H6O8·2C8H10N4O2Z = 1
Mr = 642.55F(000) = 334
Triclinic, P1Dx = 1.504 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.4570 (15) ÅCell parameters from 2842 reflections
b = 9.0490 (15) Åθ = 3.3–40.4°
c = 11.782 (2) ŵ = 0.12 mm1
α = 68.800 (11)°T = 98 K
β = 81.124 (13)°Block, colourless
γ = 73.441 (9)°0.55 × 0.30 × 0.25 mm
V = 709.3 (2) Å3
Data collection top
Rigaku AFC12 Kappa/SATURN724
diffractometer
3213 independent reflections
Radiation source: fine-focus sealed tube3006 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.020
ω scansθmax = 27.5°, θmin = 1.9°
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
h = 99
Tmin = 0.838, Tmax = 1k = 1111
4935 measured reflectionsl = 1415
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.120H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0679P)2 + 0.3025P]
where P = (Fo2 + 2Fc2)/3
3213 reflections(Δ/σ)max < 0.001
218 parametersΔρmax = 0.37 e Å3
2 restraintsΔρmin = 0.33 e Å3
Crystal data top
C10H6O8·2C8H10N4O2γ = 73.441 (9)°
Mr = 642.55V = 709.3 (2) Å3
Triclinic, P1Z = 1
a = 7.4570 (15) ÅMo Kα radiation
b = 9.0490 (15) ŵ = 0.12 mm1
c = 11.782 (2) ÅT = 98 K
α = 68.800 (11)°0.55 × 0.30 × 0.25 mm
β = 81.124 (13)°
Data collection top
Rigaku AFC12 Kappa/SATURN724
diffractometer
3213 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
3006 reflections with I > 2σ(I)
Tmin = 0.838, Tmax = 1Rint = 0.020
4935 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0442 restraints
wR(F2) = 0.120H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.37 e Å3
3213 reflectionsΔρmin = 0.33 e Å3
218 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 (Å2) top
xyzUiso*/Ueq
O10.10476 (13)0.94888 (12)0.88177 (9)0.0215 (2)
O20.05750 (13)1.21613 (12)0.85531 (9)0.0216 (2)
H1O0.0516 (16)1.226 (2)0.8350 (17)0.032*
O30.56478 (16)0.70162 (12)0.84529 (9)0.0283 (3)
O40.43724 (14)0.95115 (12)0.71641 (8)0.0202 (2)
H2O0.430 (3)0.902 (2)0.6695 (17)0.051 (6)*
O50.35494 (13)0.85084 (12)0.54930 (8)0.0225 (2)
O60.84545 (14)0.50918 (14)0.40808 (10)0.0283 (2)
N10.30711 (15)0.79348 (14)0.38575 (10)0.0189 (2)
N20.60054 (15)0.68600 (13)0.47529 (10)0.0175 (2)
N30.29341 (15)0.71840 (13)0.20867 (10)0.0180 (2)
N40.58825 (16)0.56529 (14)0.20875 (10)0.0191 (2)
C10.33603 (17)1.03685 (15)0.94094 (11)0.0162 (3)
C20.49837 (17)0.92882 (15)0.91321 (11)0.0159 (2)
C30.66122 (18)0.89199 (15)0.97280 (11)0.0168 (3)
H30.77090.81790.95440.020*
C40.15397 (18)1.06201 (16)0.88843 (11)0.0174 (3)
C50.50294 (18)0.84709 (16)0.82237 (11)0.0179 (3)
C60.41768 (18)0.78078 (16)0.47369 (11)0.0178 (3)
C70.68657 (18)0.59678 (16)0.39564 (12)0.0187 (3)
C80.56313 (18)0.62252 (15)0.30563 (11)0.0174 (3)
C90.38190 (18)0.71494 (15)0.30277 (11)0.0167 (3)
C100.42496 (19)0.62623 (16)0.15447 (12)0.0193 (3)
H100.40460.60600.08440.023*
C110.1111 (2)0.8869 (2)0.38356 (14)0.0312 (3)
H11A0.07370.93700.29910.047*
H11B0.09690.97270.41890.047*
H11C0.03160.81350.43120.047*
C120.71544 (19)0.68114 (17)0.56767 (12)0.0217 (3)
H12A0.72380.79220.55490.033*
H12B0.84140.61180.56070.033*
H12C0.65790.63620.64910.033*
C130.7597 (2)0.46116 (18)0.17183 (13)0.0251 (3)
H13A0.78550.35240.23440.038*
H13B0.86500.51020.16230.038*
H13C0.74330.45140.09410.038*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0199 (5)0.0252 (5)0.0241 (5)0.0084 (4)0.0032 (4)0.0109 (4)
O20.0180 (5)0.0209 (5)0.0262 (5)0.0038 (4)0.0101 (4)0.0055 (4)
O30.0414 (6)0.0210 (5)0.0249 (5)0.0036 (4)0.0113 (4)0.0099 (4)
O40.0250 (5)0.0225 (5)0.0154 (4)0.0064 (4)0.0052 (3)0.0072 (4)
O50.0203 (5)0.0306 (5)0.0201 (5)0.0043 (4)0.0040 (4)0.0129 (4)
O60.0192 (5)0.0350 (6)0.0301 (5)0.0028 (4)0.0086 (4)0.0147 (4)
N10.0148 (5)0.0249 (6)0.0188 (5)0.0036 (4)0.0036 (4)0.0093 (4)
N20.0159 (5)0.0215 (5)0.0163 (5)0.0054 (4)0.0039 (4)0.0059 (4)
N30.0194 (5)0.0191 (5)0.0172 (5)0.0051 (4)0.0042 (4)0.0065 (4)
N40.0196 (5)0.0205 (5)0.0193 (5)0.0056 (4)0.0017 (4)0.0083 (4)
C10.0166 (6)0.0174 (6)0.0148 (5)0.0062 (5)0.0038 (4)0.0030 (4)
C20.0186 (6)0.0170 (5)0.0140 (5)0.0067 (5)0.0030 (4)0.0048 (4)
C30.0173 (6)0.0175 (5)0.0163 (5)0.0050 (4)0.0029 (4)0.0049 (4)
C40.0167 (6)0.0227 (6)0.0139 (5)0.0064 (5)0.0019 (4)0.0060 (5)
C50.0184 (6)0.0206 (6)0.0174 (6)0.0061 (5)0.0036 (4)0.0075 (5)
C60.0175 (6)0.0205 (6)0.0163 (6)0.0067 (5)0.0023 (4)0.0050 (5)
C70.0180 (6)0.0203 (6)0.0180 (6)0.0056 (5)0.0022 (5)0.0057 (5)
C80.0178 (6)0.0187 (6)0.0161 (6)0.0052 (5)0.0015 (5)0.0056 (5)
C90.0163 (6)0.0183 (6)0.0164 (5)0.0064 (5)0.0022 (4)0.0046 (4)
C100.0228 (6)0.0189 (6)0.0176 (6)0.0064 (5)0.0042 (5)0.0058 (5)
C110.0177 (7)0.0470 (9)0.0312 (7)0.0037 (6)0.0071 (5)0.0225 (7)
C120.0188 (6)0.0291 (7)0.0198 (6)0.0061 (5)0.0065 (5)0.0090 (5)
C130.0213 (6)0.0279 (7)0.0291 (7)0.0035 (5)0.0007 (5)0.0154 (6)
Geometric parameters (Å, º) top
O1—C41.2123 (16)C1—C3i1.3911 (17)
O2—C41.3176 (16)C1—C21.4008 (18)
O2—H1O0.855 (9)C1—C41.5030 (17)
O3—C51.2057 (17)C2—C31.3935 (17)
O4—C51.3270 (15)C2—C51.4968 (17)
O4—H2O0.843 (9)C3—C1i1.3911 (17)
O5—C61.2349 (16)C3—H30.9500
O6—C71.2197 (17)C7—C81.4236 (17)
N1—C91.3713 (17)C8—C91.3698 (18)
N1—C61.3747 (16)C10—H100.9500
N1—C111.4638 (17)C11—H11A0.9800
N2—C61.3875 (17)C11—H11B0.9800
N2—C71.4181 (17)C11—H11C0.9800
N2—C121.4671 (15)C12—H12A0.9800
N3—C101.3384 (17)C12—H12B0.9800
N3—C91.3618 (16)C12—H12C0.9800
N4—C101.3410 (17)C13—H13A0.9800
N4—C81.3829 (16)C13—H13B0.9800
N4—C131.4664 (17)C13—H13C0.9800
C4—O2—H1O110.9 (13)O6—C7—N2121.91 (12)
C5—O4—H2O111.5 (16)O6—C7—C8126.89 (13)
C9—N1—C6119.13 (11)N2—C7—C8111.20 (11)
C9—N1—C11121.00 (11)C9—C8—N4105.48 (11)
C6—N1—C11119.85 (11)C9—C8—C7123.20 (12)
C6—N2—C7126.45 (11)N4—C8—C7131.32 (12)
C6—N2—C12116.05 (11)N3—C9—C8111.54 (11)
C7—N2—C12117.50 (11)N3—C9—N1126.48 (12)
C10—N3—C9103.47 (11)C8—C9—N1121.97 (11)
C10—N4—C8106.08 (11)N3—C10—N4113.43 (11)
C10—N4—C13127.01 (11)N3—C10—H10123.3
C8—N4—C13126.90 (11)N4—C10—H10123.3
C3i—C1—C2119.74 (12)N1—C11—H11A109.5
C3i—C1—C4119.61 (11)N1—C11—H11B109.5
C2—C1—C4120.31 (11)H11A—C11—H11B109.5
C3—C2—C1119.94 (11)N1—C11—H11C109.5
C3—C2—C5117.97 (11)H11A—C11—H11C109.5
C1—C2—C5122.07 (11)H11B—C11—H11C109.5
C1i—C3—C2120.31 (12)N2—C12—H12A109.5
C1i—C3—H3119.8N2—C12—H12B109.5
C2—C3—H3119.8H12A—C12—H12B109.5
O1—C4—O2125.76 (12)N2—C12—H12C109.5
O1—C4—C1121.79 (12)H12A—C12—H12C109.5
O2—C4—C1112.42 (11)H12B—C12—H12C109.5
O3—C5—O4125.01 (12)N4—C13—H13A109.5
O3—C5—C2121.87 (11)N4—C13—H13B109.5
O4—C5—C2113.10 (11)H13A—C13—H13B109.5
O5—C6—N1120.74 (12)N4—C13—H13C109.5
O5—C6—N2121.29 (11)H13A—C13—H13C109.5
N1—C6—N2117.97 (11)H13B—C13—H13C109.5
C3i—C1—C2—C30.6 (2)C6—N2—C7—C83.16 (18)
C4—C1—C2—C3172.74 (11)C12—N2—C7—C8175.68 (10)
C3i—C1—C2—C5179.23 (11)C10—N4—C8—C90.39 (14)
C4—C1—C2—C55.92 (18)C13—N4—C8—C9179.52 (12)
C1—C2—C3—C1i0.6 (2)C10—N4—C8—C7179.29 (13)
C5—C2—C3—C1i179.28 (11)C13—N4—C8—C71.6 (2)
C3i—C1—C4—O1131.94 (13)O6—C7—C8—C9175.61 (13)
C2—C1—C4—O141.37 (18)N2—C7—C8—C93.34 (18)
C3i—C1—C4—O246.39 (15)O6—C7—C8—N43.1 (2)
C2—C1—C4—O2140.30 (12)N2—C7—C8—N4177.92 (12)
C3—C2—C5—O348.27 (18)C10—N3—C9—C80.07 (14)
C1—C2—C5—O3130.41 (14)C10—N3—C9—N1179.02 (12)
C3—C2—C5—O4130.22 (12)N4—C8—C9—N30.20 (14)
C1—C2—C5—O451.09 (16)C7—C8—C9—N3179.22 (11)
C9—N1—C6—O5179.55 (11)N4—C8—C9—N1179.34 (11)
C11—N1—C6—O51.85 (19)C7—C8—C9—N11.6 (2)
C9—N1—C6—N21.00 (18)C6—N1—C9—N3178.25 (12)
C11—N1—C6—N2177.60 (12)C11—N1—C9—N33.2 (2)
C7—N2—C6—O5178.31 (12)C6—N1—C9—C80.75 (19)
C12—N2—C6—O52.83 (18)C11—N1—C9—C8177.83 (13)
C7—N2—C6—N11.14 (19)C9—N3—C10—N40.33 (15)
C12—N2—C6—N1177.72 (11)C8—N4—C10—N30.47 (15)
C6—N2—C7—O6175.85 (12)C13—N4—C10—N3179.60 (12)
C12—N2—C7—O65.31 (19)
Symmetry code: (i) x+1, y+2, z+2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H1O···N3ii0.86 (1)1.83 (1)2.6774 (17)171 (2)
O4—H2O···O50.84 (2)1.84 (2)2.6571 (15)162 (2)
C12—H12B···O6iii0.982.303.239 (2)159
Symmetry codes: (ii) x, y+2, z+1; (iii) x+2, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H1O···N3i0.855 (14)1.831 (14)2.6774 (17)170.6 (18)
O4—H2O···O50.841 (19)1.84 (2)2.6571 (15)162 (2)
C12—H12B···O6ii0.982.303.239 (2)159
Symmetry codes: (i) x, y+2, z+1; (ii) x+2, y+1, z+1.
 

Acknowledgements

The authors gratefully thank the Ministry of Higher Education (Malaysia) for funding structural studies through the High-Impact Research scheme (grant No. UM.C/HIR-MOHE/SC/03).

References

First citationArman, H. D. & Tiekink, E. R. T. (2013). Z. Kristallogr. Cryst. Mat. 228, 289–294.  Web of Science CSD CrossRef CAS
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