Tetra­kis(methyl­ammonium) benzene-1,2,4,5-tetra­carboxyl­ate dihydrate

In the title compound, 4CH₆N⁺·C₁₀H₂O₈⁴⁻·2H₂O, the complete C₁₀H₂O₈⁴⁻ anion is generated by inversion; one of the unique carboxyl­ate groups is almost coplanar with the benzene ring, perhaps as the result of intra­molecular C—H...O inter­actions, and the other is almost perpendicular. A network of O—H...O and N—H...O hydrogen bonds helps to consolidate the crystal packing.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.032
• wR factor = 0.092
• Data-to-parameter ratio = 10.2

checkCIF/PLATON results

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Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   1 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
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Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2002); cell refinement: CrysAlis RED (Oxford Diffraction, 2002); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 1990); software used to prepare material for publication: SHELXL97.

Tetrakis(methylammonium) benzene-1,2,4,5-tetracarboxylate dihydrate

Crystal data

4CH6N^+·C10H2O8^4^−·2H2O	Z = 1
Mr = 414.42	F(000) = 222
Triclinic, P1	Dx = 1.320 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.9844 (6) Å	Cell parameters from 3377 reflections
b = 8.1959 (7) Å	θ = 3.3–25.5°
c = 9.1928 (8) Å	µ = 0.11 mm^−1
α = 115.958 (8)°	T = 298 K
β = 96.233 (6)°	Block, colourless
γ = 99.896 (7)°	0.50 × 0.48 × 0.45 mm
V = 521.24 (9) Å^3

Data collection

Oxford Diffraction Xcalibur diffractometer	1673 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.016
Graphite monochromator	θmax = 25.5°, θmin = 3.3°
Detector resolution: 1024x1024 with blocks 2x2 pixels mm^-1	h = −9→9
ω scans	k = −9→9
3377 measured reflections	l = −11→9
1915 independent reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.032	All H-atom parameters refined
wR(F^2) = 0.092	w = 1/[σ^2(Fo^2) + (0.0502P)^2 + 0.0982P] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max < 0.001
1915 reflections	Δρmax = 0.20 e Å^−3
188 parameters	Δρmin = −0.15 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.168 (13)

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
N1	0.25909 (15)	0.44239 (19)	0.77132 (15)	0.0408 (3)
H1A	0.238 (3)	0.367 (3)	0.656 (3)	0.072 (6)*
H1B	0.294 (2)	0.375 (2)	0.821 (2)	0.054 (5)*
H1C	0.352 (2)	0.541 (3)	0.796 (2)	0.057 (5)*
C2	0.1024 (2)	0.5094 (4)	0.8133 (2)	0.0654 (5)
H2A	0.013 (3)	0.400 (4)	0.797 (3)	0.088 (7)*
H2B	0.132 (3)	0.600 (4)	0.931 (3)	0.096 (7)*
H2C	0.064 (3)	0.556 (3)	0.734 (3)	0.086 (7)*
N3	0.37315 (16)	0.68260 (17)	0.46879 (16)	0.0394 (3)
H3A	0.331 (2)	0.560 (3)	0.447 (2)	0.062 (5)*
H3B	0.490 (3)	0.728 (3)	0.514 (2)	0.072 (6)*
H3C	0.356 (2)	0.686 (3)	0.363 (2)	0.061 (5)*
C4	0.2790 (2)	0.8063 (2)	0.5804 (2)	0.0477 (4)
H4A	0.156 (3)	0.749 (3)	0.542 (3)	0.086 (7)*
H4B	0.311 (3)	0.816 (3)	0.690 (3)	0.080 (6)*
H4C	0.304 (3)	0.920 (4)	0.577 (3)	0.087 (7)*
C6	0.16487 (14)	0.12040 (15)	0.03709 (13)	0.0237 (3)
C5	0.10194 (14)	0.08727 (15)	0.16048 (13)	0.0234 (3)
C7	0.06043 (14)	0.03280 (16)	−0.12093 (14)	0.0253 (3)
H7	0.1034 (17)	0.0554 (18)	−0.2055 (16)	0.028 (3)*
C8	0.19744 (15)	0.18080 (17)	0.33872 (14)	0.0295 (3)
O9	0.18068 (13)	0.34054 (13)	0.43079 (11)	0.0453 (3)
O10	0.27804 (13)	0.09052 (15)	0.38743 (12)	0.0489 (3)
C11	0.34390 (14)	0.24237 (16)	0.06758 (14)	0.0279 (3)
O12	0.38470 (11)	0.26855 (14)	−0.05010 (11)	0.0418 (3)
O13	0.44075 (11)	0.30816 (15)	0.20629 (11)	0.0447 (3)
O14	0.33097 (16)	0.74525 (19)	0.19681 (16)	0.0560 (3)
H14A	0.420 (3)	0.751 (3)	0.154 (3)	0.091 (7)*
H14B	0.319 (3)	0.874 (4)	0.253 (3)	0.101 (8)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0330 (6)	0.0533 (7)	0.0286 (6)	−0.0082 (5)	−0.0011 (5)	0.0210 (6)
C2	0.0439 (9)	0.0945 (15)	0.0491 (10)	0.0088 (10)	0.0077 (8)	0.0292 (10)
N3	0.0315 (6)	0.0371 (7)	0.0408 (7)	0.0048 (5)	0.0021 (5)	0.0131 (5)
C4	0.0498 (9)	0.0497 (9)	0.0439 (9)	0.0171 (7)	0.0135 (7)	0.0194 (7)
C6	0.0215 (6)	0.0241 (6)	0.0227 (5)	0.0029 (4)	0.0030 (4)	0.0098 (4)
C5	0.0223 (5)	0.0236 (5)	0.0209 (5)	0.0030 (4)	0.0019 (4)	0.0089 (4)
C7	0.0256 (6)	0.0284 (6)	0.0211 (5)	0.0030 (4)	0.0056 (4)	0.0119 (5)
C8	0.0258 (6)	0.0341 (6)	0.0224 (6)	−0.0040 (5)	0.0012 (5)	0.0126 (5)
O9	0.0519 (6)	0.0385 (6)	0.0261 (5)	0.0010 (4)	0.0033 (4)	0.0028 (4)
O10	0.0498 (6)	0.0538 (6)	0.0408 (6)	0.0036 (5)	−0.0110 (4)	0.0277 (5)
C11	0.0240 (6)	0.0284 (6)	0.0281 (6)	0.0012 (5)	0.0037 (5)	0.0125 (5)
O12	0.0320 (5)	0.0544 (6)	0.0390 (5)	−0.0051 (4)	0.0066 (4)	0.0274 (5)
O13	0.0279 (5)	0.0587 (6)	0.0364 (5)	−0.0126 (4)	−0.0058 (4)	0.0234 (5)
O14	0.0510 (7)	0.0654 (8)	0.0602 (7)	0.0132 (6)	0.0216 (6)	0.0349 (6)

Geometric parameters (Å, º)

N1—C2	1.474 (2)	C6—C7	1.3925 (15)
N1—H1A	0.94 (2)	C6—C5	1.3998 (15)
N1—H1B	0.918 (19)	C6—C11	1.5158 (15)
N1—H1C	0.927 (19)	C5—C7^i	1.3882 (16)
C2—H2A	0.98 (3)	C5—C8	1.5106 (15)
C2—H2B	0.98 (3)	C7—C5^i	1.3882 (16)
C2—H2C	1.01 (2)	C7—H7	0.959 (14)
N3—C4	1.472 (2)	C8—O10	1.246 (2)
N3—H3A	0.93 (2)	C8—O9	1.250 (2)
N3—H3B	0.92 (2)	C11—O13	1.247 (1)
N3—H3C	0.98 (2)	C11—O12	1.256 (1)
C4—H4A	0.97 (2)	O14—H14A	0.86 (3)
C4—H4B	0.97 (2)	O14—H14B	0.98 (3)
C4—H4C	0.93 (3)
C2—N1—H1A	108.2 (12)	H4A—C4—H4B	107.1 (18)
C2—N1—H1B	115.7 (11)	N3—C4—H4C	107.7 (14)
H1A—N1—H1B	108.3 (17)	H4A—C4—H4C	109.7 (19)
C2—N1—H1C	110.9 (11)	H4B—C4—H4C	114.9 (19)
H1A—N1—H1C	105.7 (16)	C7—C6—C5	118.41 (10)
H1B—N1—H1C	107.5 (15)	C7—C6—C11	118.98 (10)
N1—C2—H2A	106.7 (14)	C5—C6—C11	122.58 (10)
N1—C2—H2B	106.9 (14)	C7^i—C5—C6	119.13 (10)
H2A—C2—H2B	108.9 (19)	C7^i—C5—C8	116.95 (10)
N1—C2—H2C	107.5 (13)	C6—C5—C8	123.88 (9)
H2A—C2—H2C	109.6 (19)	C5^i—C7—C6	122.46 (10)
H2B—C2—H2C	117 (2)	C5^i—C7—H7	119.1 (8)
C4—N3—H3A	111.0 (11)	C6—C7—H7	118.5 (8)
C4—N3—H3B	108.7 (13)	O10—C8—O9	124.1 (1)
H3A—N3—H3B	113.0 (17)	O10—C8—C5	118.5 (1)
C4—N3—H3C	109.8 (11)	O9—C8—C5	117.3 (1)
H3A—N3—H3C	107.2 (16)	O13—C11—O12	124.6 (1)
H3B—N3—H3C	106.9 (16)	O13—C11—C6	118.1 (1)
N3—C4—H4A	108.8 (13)	O12—C11—C6	117.3 (1)
N3—C4—H4B	108.4 (12)	H14A—O14—H14B	105 (2)
C7—C6—C5—C7^i	0.79 (18)	C6—C5—C8—O10	−101.5 (1)
C11—C6—C5—C7^i	−177.16 (10)	C7^i—C5—C8—O9	−94.4 (1)
C7—C6—C5—C8	−176.70 (10)	C6—C5—C8—O9	83.1 (1)
C11—C6—C5—C8	5.35 (17)	C7—C6—C11—O13	−174.6 (1)
C5—C6—C7—C5^i	−0.82 (18)	C5—C6—C11—O13	3.3 (2)
C11—C6—C7—C5^i	177.21 (10)	C7—C6—C11—O12	4.7 (2)
C7^i—C5—C8—O10	81.0 (1)	C5—C6—C11—O12	−177.3 (1)

Symmetry code: (i) −x, −y, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O9	0.94 (2)	1.98 (2)	2.828 (2)	149 (2)
N1—H1B···O12^ii	0.92 (2)	1.90 (2)	2.813 (2)	172 (2)
N1—H1C···O13^iii	0.93 (2)	1.89 (2)	2.794 (2)	164 (2)
N3—H3A···O9	0.93 (2)	1.92 (2)	2.809 (2)	160 (2)
N3—H3B···O10^iii	0.92 (2)	2.00 (2)	2.869 (2)	159 (2)
N3—H3C···O14	0.98 (2)	1.80 (2)	2.762 (2)	167 (2)
O14—H14A···O12^iv	0.86 (3)	1.91 (3)	2.758 (2)	173 (2)
O14—H14B···O10^v	0.98 (3)	1.77 (3)	2.736 (2)	166 (2)
C2—H2B···O14^ii	0.98 (3)	2.43 (3)	3.305 (2)	149 (2)
C7—H7···O12	0.96 (1)	2.43 (1)	2.770 (1)	100.5 (9)

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