Guanidinium pyromellitate

The title compound, guanidinium pyromellitate, 2[C(NH₂)₃]⁺·(C₁₀H₄O₈)²⁻ or 2 CH₆N₃⁺·C₁₀H₄O₈²⁻, comprises a 1,2,4,5-benzene­tetra­carboxyl­ate anion and two guanidinium cations. The carboxyl­ate anions lie on centers of inversion and involve intramolecular O—H...O hydrogen bonds. The cations and anions are linked by strong three-dimensional N—H...O hydrogen bonds and π–π-stacking interactions into a three-dimensional framework containing a one-dimensional channel along the diagonal of the ca plane. The N—H...O hydrogen-bond distances range from 2.899 (6) to 3.068 (5) Å.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.054
• wR factor = 0.148
• Data-to-parameter ratio = 9.1

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level A:



PLAT_738  Alert A D-H..A  Calc      167(3), Rep    167.0(3) ....       9.90 s.u-Ratio
                     N2   -H6   -O4      1.555   1.555   1.555

PLAT_738  Alert A D-H..A  Calc      166(3), Rep    166.0(3) ....       9.90 s.u-Ratio
                     N1   -H4   -O3      1.555   1.555   1.555


 Alert Level C:



PLAT_369  Alert C Long   C(sp2)-C(sp2) Bond  C(1)   -   C(2)   =       1.53 Ang.


 2 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 1 Alert Level C = Please check

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Computing details

Data collection: Bruker SMART; cell refinement: SMART (Bruker, 1999); data reduction: SHELXTL (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Guanidium Dihydrigen 1,2,4,5-Benzenetetracarboxylate

Crystal data

2CH6N3^+·C10H4O8^2^−	F(000) = 388.0
Mr = 372.31	Dx = 1.583 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 172 reflections
a = 3.7949 (2) Å	θ = 2.0–25.1°
b = 20.1494 (9) Å	µ = 0.14 mm^−1
c = 10.3903 (1) Å	T = 293 K
β = 100.501 (3)°	Column, colorless
V = 781.19 (5) Å^3	0.36 × 0.30 × 0.18 mm
Z = 2

Data collection

Siemems SMART CCD diffractometer	1372 independent reflections
Radiation source: fine-focus sealed tube	1132 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.029
φ and ω scans	θmax = 25.1°, θmin = 2.0°
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick, 1996)	h = −4→4
Tmin = 0.953, Tmax = 0.976	k = −23→21
2373 measured reflections	l = −4→12

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)] = 0.054	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.148	All H-atom parameters refined
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0666P)^2 + 0.7112P] where P = (Fo^2 + 2Fc^2)/3
1372 reflections	(Δ/σ)max < 0.001
150 parameters	Δρmax = 0.19 e Å^−3
0 restraints	Δρmin = −0.26 e Å^−3

Special details

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	−0.5083 (7)	0.31950 (9)	−0.1084 (2)	0.0581 (7)
O2	−0.1462 (7)	0.33475 (9)	0.0773 (2)	0.0591 (7)
O3	0.0721 (6)	0.51806 (9)	0.31938 (19)	0.0527 (6)
O4	−0.0975 (7)	0.61919 (10)	0.2694 (2)	0.0634 (8)
C1	−0.3648 (8)	0.35664 (12)	−0.0135 (2)	0.0392 (6)
C2	−0.4587 (7)	0.43044 (12)	−0.0153 (2)	0.0324 (6)
C3	−0.2947 (7)	0.46460 (12)	0.0956 (2)	0.0344 (6)
C4	−0.3250 (7)	0.53268 (11)	0.1159 (2)	0.0313 (6)
C5	−0.1034 (7)	0.55706 (13)	0.2438 (2)	0.0371 (6)
C6	0.5571 (8)	0.65754 (13)	0.5549 (2)	0.0389 (6)
N1	0.4783 (8)	0.59360 (12)	0.5571 (3)	0.0520 (7)
N2	0.4135 (8)	0.69461 (13)	0.4543 (2)	0.0487 (7)
N3	0.7720 (8)	0.68548 (13)	0.6546 (3)	0.0514 (7)
H7	−0.138 (7)	0.4393 (13)	0.165 (3)	0.029 (6)*
H6	0.255 (9)	0.6772 (15)	0.389 (3)	0.049 (9)*
H5	0.473 (9)	0.7340 (19)	0.455 (3)	0.062 (10)*
H4	0.329 (8)	0.5770 (15)	0.487 (3)	0.049 (8)*
H3	0.867 (9)	0.6630 (17)	0.723 (4)	0.060 (10)*
H2	0.850 (9)	0.7266 (18)	0.643 (3)	0.059 (9)*
H1	0.619 (10)	0.5681 (18)	0.617 (4)	0.071 (11)*
H8	−0.301 (10)	0.6509 (18)	0.192 (4)	0.071 (10)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0856 (16)	0.0274 (10)	0.0502 (12)	0.0113 (10)	−0.0170 (11)	−0.0102 (9)
O2	0.0905 (17)	0.0297 (10)	0.0465 (12)	0.0165 (10)	−0.0155 (11)	−0.0029 (9)
O3	0.0759 (14)	0.0353 (10)	0.0384 (11)	0.0045 (10)	−0.0122 (10)	−0.0006 (9)
O4	0.0917 (17)	0.0301 (11)	0.0535 (13)	0.0061 (11)	−0.0265 (12)	−0.0108 (9)
C1	0.0579 (16)	0.0252 (13)	0.0329 (13)	0.0039 (12)	0.0041 (12)	−0.0019 (11)
C2	0.0443 (14)	0.0235 (12)	0.0303 (12)	0.0001 (10)	0.0091 (10)	−0.0012 (10)
C3	0.0469 (14)	0.0259 (13)	0.0291 (13)	0.0017 (11)	0.0033 (11)	0.0012 (10)
C4	0.0425 (13)	0.0250 (12)	0.0277 (12)	0.0005 (10)	0.0095 (11)	−0.0012 (9)
C5	0.0498 (15)	0.0280 (13)	0.0320 (13)	0.0004 (11)	0.0037 (11)	−0.0042 (11)
C6	0.0524 (15)	0.0280 (13)	0.0349 (13)	−0.0002 (11)	0.0044 (12)	0.0003 (11)
N1	0.0734 (18)	0.0276 (12)	0.0477 (15)	−0.0041 (12)	−0.0085 (14)	0.0023 (11)
N2	0.0727 (17)	0.0286 (13)	0.0374 (13)	−0.0054 (12)	−0.0098 (12)	0.0012 (10)
N3	0.0733 (18)	0.0333 (13)	0.0412 (14)	−0.0079 (13)	−0.0064 (13)	0.0052 (11)

Geometric parameters (Å, º)

O1—C1	1.278 (3)	C3—C4	1.396 (3)
O2—C1	1.220 (3)	C4—C2^i	1.416 (3)
O3—C5	1.219 (3)	C4—C5	1.519 (3)
O4—C5	1.279 (3)	C6—N2	1.319 (3)
C1—C2	1.529 (3)	C6—N1	1.324 (4)
C2—C3	1.388 (3)	C6—N3	1.322 (4)
C2—C4^i	1.416 (3)
O2—C1—O1	121.3 (2)	C3—C4—C5	113.8 (2)
O2—C1—C2	119.0 (2)	C2^i—C4—C5	129.1 (2)
O1—C1—C2	119.6 (2)	O3—C5—O4	120.7 (2)
C3—C2—C4^i	117.7 (2)	O3—C5—C4	120.3 (2)
C3—C2—C1	113.8 (2)	O4—C5—C4	119.0 (2)
C4^i—C2—C1	128.5 (2)	N2—C6—N1	120.2 (3)
C2—C3—C4	125.2 (2)	N2—C6—N3	119.1 (3)
C3—C4—C2^i	117.1 (2)	N1—C6—N3	120.6 (3)

Symmetry code: (i) −x−1, −y+1, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H6···O4	0.89 (3)	2.02 (3)	2.899 (3)	167.0 (3)
N2—H5···O2^ii	0.82 (4)	2.18 (4)	2.994 (3)	169.0 (6)
N1—H4···O3	0.90 (3)	2.19 (3)	3.067 (4)	166.0 (3)
N3—H3···O2^iii	0.86 (4)	2.15 (4)	2.916 (4)	147.0 (2)
N3—H2···O1^ii	0.90 (4)	2.02 (4)	2.913 (3)	177.2 (9)
N1—H1···O3^iii	0.90 (4)	2.13 (4)	2.970 (3)	153.8 (9)
O4—H8···O1^i	1.19 (4)	1.19 (4)	2.377 (3)	175.6 (4)

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