A second monoclinic modification of benzimidazolium 3-carboxy­phenoxy­acetate 3-carboxy­phenoxy­acetic acid

Gao, S.; Huo, L.-H.; Gu, C.-S.; Zhao, H.; Ng, S.W.

doi:10.1107/S1600536804024158

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A second monoclinic modification of benzimidazolium 3-carboxyphenoxyacetate 3-carboxyphenoxyacetic acid

S. Gao, L.-H. Huo, C.-S. Gu, H. Zhao and S. W. Ng

In the primitive monoclinic modification of the title compound, C₇H₇N₂⁺·C₉H₇O₅⁻·C₉H₈O₅, the two monoanions are connected by an `acid' O—H

O hydrogen bond whose H atom does not lie on a special position. This acid hydrogen atom and the two monoanions comprise a carboxylate monoanion/neutral molecule in which the acid H atom is disordered between the two monoanionic units. The chains are connected into a layer structure through the C₇H₇N₂⁺ cations via N—H

O hydrogen bonds.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536804024158/lh6280sup1.cif Contains datablocks I, global
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536804024158/lh6280Isup2.hkl Contains datablock I

CCDC reference: 255474

checkCIF report

Key indicators

Single-crystal X-ray study
T = 295 K
Mean (C-C) = 0.003 Å
R factor = 0.051
wR factor = 0.123
Data-to-parameter ratio = 14.5

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT432_ALERT_2_B Short Inter X...Y Contact  O10    ..  C19     ..       2.89 Ang.

Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.782     0.979
            Tmin' and Tmax expected:      0.951     0.979
            RR' =      0.822
            Please check that your absorption correction is appropriate.
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.82
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.20
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.54

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

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

Computing details top

Data collection: RAPID-AUTO (Rigaku Corporation, 1998); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku/MSC and Rigaku Corporation, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.

Benzimidazolium 3-carboxyphenoxyacetate 3-carboxyphenoxyacetatic acid top

Crystal data top

C₇H₇N₂⁺·C₉H₇O₅⁻·C₉H₈O₅	F(000) = 1064
M_r = 510.45	D_x = 1.490 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 17563 reflections
a = 7.647 (2) Å	θ = 3.1–27.2°
b = 21.158 (4) Å	µ = 0.12 mm⁻¹
c = 14.122 (3) Å	T = 295 K
β = 95.08 (3)°	Prism, colorless
V = 2276.1 (8) Å³	0.42 × 0.26 × 0.18 mm
Z = 4

Data collection top

Rigaku R-AXIS RAPID diffractometer	5193 independent reflections
Radiation source: fine-focus sealed tube	3394 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.051
ω scan	θ_max = 27.5°, θ_min = 3.1°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −9→8
T_min = 0.782, T_max = 0.979	k = −27→27
21472 measured reflections	l = −18→18

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.051	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.123	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	w = 1/[σ²(F_o²) + (0.0626P)² + 0.2455P] where P = (F_o² + 2F_c²)/3
5193 reflections	(Δ/σ)_max = 0.001
359 parameters	Δρ_max = 0.25 e Å⁻³
6 restraints	Δρ_min = −0.18 e Å⁻³

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
O1	0.4758 (2)	0.6183 (1)	0.8870 (1)	0.0433 (3)
O2	0.5925 (2)	0.7144 (1)	0.9069 (1)	0.0558 (4)
O3	0.3817 (2)	0.5805 (1)	0.5463 (1)	0.0516 (4)
O4	0.2066 (2)	0.4864 (1)	0.4638 (1)	0.0476 (4)
O5	0.2469 (2)	0.5195 (1)	0.3187 (1)	0.0525 (4)
O6	0.4204 (2)	0.6362 (1)	0.0786 (1)	0.0450 (4)
O7	0.3688 (2)	0.6065 (1)	0.2232 (1)	0.0515 (4)
O8	0.2920 (2)	0.5337 (1)	−0.0017 (1)	0.0445 (4)
O9	0.2160 (2)	0.4921 (1)	−0.3429 (1)	0.0507 (4)
O10	0.1561 (3)	0.3901 (1)	−0.3596 (1)	0.0836 (6)
N1	0.0380 (2)	0.3722 (1)	0.4129 (1)	0.0467 (4)
N2	−0.0446 (2)	0.2750 (1)	0.4234 (1)	0.0481 (4)
C1	0.5410 (2)	0.6713 (1)	0.8553 (1)	0.0362 (4)
C2	0.4680 (2)	0.6255 (1)	0.6935 (1)	0.0357 (4)
C3	0.5437 (2)	0.6732 (1)	0.7501 (1)	0.0329 (4)
C4	0.6178 (2)	0.7256 (1)	0.7087 (1)	0.0363 (4)
C5	0.6134 (3)	0.7293 (1)	0.6114 (1)	0.0412 (5)
C6	0.5354 (3)	0.6821 (1)	0.5539 (1)	0.0417 (5)
C7	0.4631 (3)	0.6301 (1)	0.5951 (1)	0.0364 (4)
C8	0.3698 (3)	0.5815 (1)	0.4459 (1)	0.0421 (5)
C9	0.2666 (3)	0.5245 (1)	0.4080 (1)	0.0390 (4)
C10	0.3668 (2)	0.5971 (1)	0.1324 (1)	0.0347 (4)
C11	0.2938 (3)	0.5339 (1)	0.0981 (1)	0.0340 (4)
C12	0.2325 (2)	0.4806 (1)	−0.0505 (1)	0.0324 (4)
C13	0.1756 (2)	0.4262 (1)	−0.0087 (1)	0.0369 (4)
C14	0.1202 (3)	0.3754 (1)	−0.0661 (1)	0.0418 (5)
C15	0.1190 (3)	0.3789 (1)	−0.1633 (1)	0.0413 (5)
C16	0.1767 (2)	0.4338 (1)	−0.2049 (1)	0.0345 (4)
C17	0.2340 (2)	0.4847 (1)	−0.1485 (1)	0.0339 (4)
C18	0.1802 (3)	0.4361 (1)	−0.3102 (1)	0.0427 (5)
C19	0.0137 (3)	0.3251 (1)	0.4710 (2)	0.0520 (5)
C20	−0.0076 (2)	0.3518 (1)	0.3207 (1)	0.0362 (4)
C21	−0.0098 (3)	0.3825 (1)	0.2348 (2)	0.0476 (5)
C22	−0.0695 (3)	0.3484 (1)	0.1568 (2)	0.0557 (6)
C23	−0.1192 (3)	0.2855 (1)	0.1624 (2)	0.0556 (6)
C24	−0.1148 (3)	0.2536 (1)	0.2480 (2)	0.0476 (5)
C25	−0.0595 (3)	0.2890 (1)	0.3279 (1)	0.0366 (4)
H1o	0.463 (3)	0.623 (1)	0.947 (1)	0.07 (1)*
H5o	0.27 (1)	0.553 (2)	0.287 (4)	0.08 (3)*	0.42 (7)
H7o	0.329 (5)	0.575 (1)	0.253 (2)	0.04 (2)*	0.58 (7)
H9o	0.217 (3)	0.489 (1)	−0.404 (1)	0.07 (1)*
H1n	0.081 (3)	0.409 (1)	0.429 (2)	0.07 (1)*
H2n	−0.062 (4)	0.239 (1)	0.451 (2)	0.08 (1)*
H2	0.4203	0.5904	0.7212	0.043*
H4	0.6697	0.7576	0.7466	0.044*
H5	0.6633	0.7640	0.5836	0.049*
H6	0.5319	0.6854	0.4881	0.050*
H8a	0.4866	0.5807	0.4240	0.050*
H8b	0.3118	0.6199	0.4226	0.050*
H11a	0.3669	0.4998	0.1252	0.041*
H11b	0.1759	0.5283	0.1169	0.041*
H13	0.1744	0.4236	0.0570	0.044*
H14	0.0832	0.3385	−0.0383	0.050*
H15	0.0799	0.3448	−0.2010	0.050*
H17	0.2731	0.5213	−0.1762	0.041*
H19	0.0349	0.3271	0.5368	0.062*
H21	0.0274	0.4241	0.2302	0.057*
H22	−0.0772	0.3679	0.0976	0.067*
H23	−0.1568	0.2641	0.1068	0.067*
H24	−0.1466	0.2113	0.2519	0.057*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.061 (1)	0.044 (1)	0.025 (1)	−0.008 (1)	0.003 (1)	0.001 (1)
O2	0.087 (1)	0.050 (1)	0.031 (1)	−0.015 (1)	0.008 (1)	−0.010 (1)
O3	0.076 (1)	0.057 (1)	0.022 (1)	−0.029 (1)	0.005 (1)	−0.004 (1)
O4	0.067 (1)	0.049 (1)	0.028 (1)	−0.017 (1)	0.006 (1)	0.000 (1)
O5	0.078 (1)	0.056 (1)	0.023 (1)	−0.021 (1)	0.004 (1)	−0.003 (1)
O6	0.069 (1)	0.037 (1)	0.030 (1)	−0.010 (1)	0.009 (1)	0.002 (1)
O7	0.083 (1)	0.049 (1)	0.024 (1)	−0.020 (1)	0.009 (1)	−0.005 (1)
O8	0.075 (1)	0.038 (1)	0.021 (1)	−0.017 (1)	0.006 (1)	−0.001 (1)
O9	0.083 (1)	0.047 (1)	0.023 (1)	−0.014 (1)	0.010 (1)	−0.001 (1)
O10	0.166 (2)	0.052 (1)	0.034 (1)	−0.027 (1)	0.013 (1)	−0.014 (1)
N1	0.049 (1)	0.039 (1)	0.050 (1)	−0.002 (1)	−0.003 (1)	−0.009 (1)
N2	0.059 (1)	0.046 (1)	0.038 (1)	−0.004 (1)	−0.003 (1)	0.011 (1)
C1	0.041 (1)	0.040 (1)	0.028 (1)	0.002 (1)	0.002 (1)	−0.003 (1)
C2	0.045 (1)	0.038 (1)	0.026 (1)	−0.007 (1)	0.007 (1)	0.001 (1)
C3	0.034 (1)	0.036 (1)	0.029 (1)	0.003 (1)	0.004 (1)	−0.002 (1)
C4	0.039 (1)	0.032 (1)	0.037 (1)	0.000 (1)	0.003 (1)	−0.003 (1)
C5	0.050 (1)	0.035 (1)	0.040 (1)	−0.004 (1)	0.009 (1)	0.006 (1)
C6	0.055 (1)	0.046 (1)	0.025 (1)	−0.006 (1)	0.007 (1)	0.003 (1)
C7	0.042 (1)	0.039 (1)	0.028 (1)	−0.007 (1)	0.004 (1)	−0.003 (1)
C8	0.057 (1)	0.048 (1)	0.022 (1)	−0.009 (1)	0.006 (1)	0.001 (1)
C9	0.050 (1)	0.043 (1)	0.024 (1)	−0.003 (1)	0.005 (1)	0.000 (1)
C10	0.044 (1)	0.036 (1)	0.024 (1)	−0.001 (1)	0.004 (1)	−0.001 (1)
C11	0.045 (1)	0.039 (1)	0.019 (1)	−0.003 (1)	0.004 (1)	0.002 (1)
C12	0.038 (1)	0.033 (1)	0.026 (1)	−0.004 (1)	0.003 (1)	−0.003 (1)
C13	0.045 (1)	0.041 (1)	0.025 (1)	−0.004 (1)	0.006 (1)	0.004 (1)
C14	0.056 (1)	0.033 (1)	0.037 (1)	−0.008 (1)	0.010 (1)	0.004 (1)
C15	0.053 (1)	0.036 (1)	0.036 (1)	−0.009 (1)	0.007 (1)	−0.007 (1)
C16	0.040 (1)	0.035 (1)	0.028 (1)	−0.001 (1)	0.005 (1)	−0.002 (1)
C17	0.044 (1)	0.032 (1)	0.026 (1)	−0.004 (1)	0.006 (1)	0.001 (1)
C18	0.061 (1)	0.041 (1)	0.027 (1)	−0.006 (1)	0.005 (1)	−0.005 (1)
C19	0.057 (1)	0.063 (1)	0.035 (1)	0.001 (1)	−0.001 (1)	0.000 (1)
C20	0.036 (1)	0.033 (1)	0.040 (1)	0.002 (1)	0.004 (1)	0.000 (1)
C21	0.047 (1)	0.044 (1)	0.053 (1)	0.002 (1)	0.011 (1)	0.017 (1)
C22	0.052 (1)	0.077 (2)	0.040 (1)	0.008 (1)	0.014 (1)	0.016 (1)
C23	0.056 (1)	0.076 (2)	0.036 (1)	0.009 (1)	0.004 (1)	−0.016 (1)
C24	0.049 (1)	0.040 (1)	0.054 (1)	0.000 (1)	0.002 (1)	−0.010 (1)
C25	0.041 (1)	0.034 (1)	0.035 (1)	0.001 (1)	0.002 (1)	0.0055 (1)

Geometric parameters (Å, º) top

O1—C1	1.322 (2)	C16—C18	1.491 (3)
O2—C1	1.210 (2)	C20—C21	1.375 (3)
O3—C7	1.373 (2)	C20—C25	1.392 (3)
O3—C8	1.414 (2)	C21—C22	1.361 (3)
O4—C9	1.243 (2)	C22—C23	1.388 (3)
O5—C9	1.261 (2)	C23—C24	1.383 (3)
O6—C10	1.219 (2)	C24—C25	1.389 (3)
O7—C10	1.296 (2)	O1—H1o	0.87 (2)
O8—C12	1.373 (2)	O5—H5o	0.85 (2)
O8—C11	1.408 (2)	O7—H7o	0.86 (2)
O9—C18	1.309 (2)	O9—H9o	0.86 (2)
O10—C18	1.201 (2)	N1—H1n	0.86 (2)
N1—C19	1.315 (3)	N2—H2n	0.87 (2)
N1—C20	1.387 (3)	C2—H2	0.93
N2—C19	1.313 (3)	C4—H4	0.93
N2—C25	1.377 (2)	C5—H5	0.93
C1—C3	1.489 (2)	C6—H6	0.93
C2—C3	1.383 (3)	C8—H8a	0.97
C2—C7	1.389 (2)	C8—H8b	0.97
C3—C4	1.395 (3)	C11—H11a	0.97
C4—C5	1.373 (3)	C11—H11b	0.97
C5—C6	1.388 (3)	C13—H13	0.93
C6—C7	1.383 (3)	C14—H14	0.93
C8—C9	1.513 (3)	C15—H15	0.93
C10—C11	1.512 (3)	C17—H17	0.93
C12—C13	1.381 (2)	C19—H19	0.93
C12—C17	1.388 (2)	C21—H21	0.93
C13—C14	1.389 (3)	C22—H22	0.93
C14—C15	1.374 (3)	C23—H23	0.93
C15—C16	1.390 (3)	C24—H24	0.93
C16—C17	1.387 (2)

C7—O3—C8	118.6 (1)	N2—C25—C24	132.2 (2)
C11—O8—C12	118.6 (1)	C20—C25—C24	121.7 (2)
C19—N1—C20	108.2 (2)	C1—O1—H1o	109 (2)
C19—N2—C25	108.8 (2)	C9—O5—H5o	116 (5)
O1—C1—O2	123.2 (2)	C10—O7—H7o	113 (3)
O1—C1—C3	113.6 (2)	C18—O9—H9o	107 (2)
O2—C1—C3	123.2 (2)	C19—N1—H1n	126 (2)
C3—C2—C7	120.0 (2)	C20—N1—H1n	126 (2)
C2—C3—C4	120.2 (2)	C19—N2—H2n	122 (2)
C1—C3—C2	121.0 (2)	C25—N2—H2n	129 (2)
C1—C3—C4	118.8 (2)	C3—C2—H2	120.0
C3—C4—C5	119.3 (2)	C7—C2—H2	120.0
C4—C5—C6	121.0 (2)	C5—C4—H4	120.4
C5—C6—C7	119.6 (2)	C3—C4—H4	120.4
O3—C7—C2	114.8 (2)	C4—C5—H5	119.5
O3—C7—C6	125.2 (2)	C6—C5—H5	119.5
C2—C7—C6	120.0 (2)	C7—C6—H6	120.2
O3—C8—C9	109.1 (2)	C5—C6—H6	120.2
O4—C9—O5	124.1 (2)	O3—C8—H8a	109.9
O4—C9—C8	120.2 (2)	C9—C8—H8a	109.9
O5—C9—C8	115.7 (2)	O3—C8—H8b	109.9
O6—C10—O7	122.5 (2)	C9—C8—H8b	109.9
O6—C10—C11	122.3 (2)	H8a—C8—H8b	108.3
O7—C10—C11	115.2 (2)	O8—C11—H11a	110.3
O8—C11—C10	107.2 (1)	C10—C11—H11a	110.3
O8—C12—C13	124.8 (2)	O8—C11—H11b	110.3
O8—C12—C17	114.7 (2)	C10—C11—H11b	110.3
C13—C12—C17	120.5 (2)	H11a—C11—H11b	108.5
C12—C13—C14	119.2 (2)	C12—C13—H13	120.4
C13—C14—C15	121.0 (2)	C14—C13—H13	120.4
C14—C15—C16	119.6 (2)	C15—C14—H14	119.5
C15—C16—C17	120.1 (2)	C13—C14—H14	119.5
C15—C16—C18	118.9 (2)	C14—C15—H15	120.2
C17—C16—C18	121.0 (2)	C16—C15—H15	120.2
C12—C17—C16	119.6 (2)	C12—C17—H17	120.2
O10—C18—O9	123.6 (2)	C16—C17—H17	120.2
O9—C18—C16	113.9 (2)	N2—C19—H19	124.7
O10—C18—C16	122.5 (2)	N1—C19—H19	124.7
N1—C19—N2	110.7 (2)	C22—C21—H21	121.9
N1—C20—C21	131.6 (2)	C20—C21—H21	121.9
N1—C20—C25	106.2 (2)	C21—C22—H22	118.8
C21—C20—C25	122.2 (2)	C23—C22—H22	118.8
C20—C21—C22	116.1 (2)	C24—C23—H23	118.9
C21—C22—C23	122.4 (2)	C22—C23—H23	118.9
C22—C23—C24	122.2 (2)	C23—C24—H24	122.3
C23—C24—C25	115.3 (2)	C25—C24—H24	122.3
N2—C25—C20	106.1 (2)

C7—C2—C3—C4	−1.0 (3)	C14—C15—C16—C17	−0.4 (3)
C7—C2—C3—C1	176.3 (2)	C14—C15—C16—C18	178.0 (2)
O2—C1—C3—C2	−173.7 (2)	C15—C16—C17—C12	−0.3 (3)
O1—C1—C3—C2	5.9 (2)	C18—C16—C17—C12	−178.7 (2)
O2—C1—C3—C4	3.6 (3)	O8—C12—C17—C16	180.0 (2)
O1—C1—C3—C4	−176.9 (2)	C13—C12—C17—C16	0.4 (3)
C2—C3—C4—C5	0.5 (3)	C17—C16—C18—O10	168.9 (2)
C1—C3—C4—C5	−176.8 (2)	C15—C16—C18—O10	−9.5 (3)
C3—C4—C5—C6	0.4 (3)	C17—C16—C18—O9	−9.5 (3)
C4—C5—C6—C7	−0.8 (3)	C15—C16—C18—O9	172.1 (2)
C8—O3—C7—C6	0.3 (3)	C25—N2—C19—N1	0.3 (3)
C8—O3—C7—C2	179.6 (2)	C20—N1—C19—N2	0.1 (3)
C5—C6—C7—O3	179.6 (2)	C19—N1—C20—C21	178.5 (2)
C5—C6—C7—C2	0.3 (3)	C19—N1—C20—C25	−0.4 (2)
C3—C2—C7—O3	−178.8 (2)	N1—C20—C21—C22	−177.4 (2)
C3—C2—C7—C6	0.6 (3)	C25—C20—C21—C22	1.4 (3)
C7—O3—C8—C9	−176.8 (2)	C20—C21—C22—C23	−2.4 (3)
O3—C8—C9—O4	0.7 (3)	C21—C22—C23—C24	1.3 (3)
O3—C8—C9—O5	−179.7 (2)	C22—C23—C24—C25	0.9 (3)
C12—O8—C11—C10	179.3 (2)	C19—N2—C25—C24	−179.7 (2)
O6—C10—C11—O8	−3.7 (2)	C19—N2—C25—C20	−0.6 (2)
O7—C10—C11—O8	176.5 (2)	C23—C24—C25—N2	177.1 (2)
C11—O8—C12—C13	−0.9 (3)	C23—C24—C25—C20	−1.8 (3)
C11—O8—C12—C17	179.5 (2)	C21—C20—C25—N2	−178.5 (2)
O8—C12—C13—C14	−179.4 (2)	N1—C20—C25—N2	0.6 (2)
C17—C12—C13—C14	0.2 (3)	C21—C20—C25—C24	0.7 (3)
C12—C13—C14—C15	−0.9 (3)	N1—C20—C25—C24	179.8 (2)
C13—C14—C15—C16	1.0 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1o···O6ⁱ	0.87 (2)	1.93 (2)	2.800 (2)	176 (2)
O5—H5o···O7	0.85 (2)	1.69 (3)	2.511 (2)	161 (7)
O7—H7o···O5	0.86 (2)	1.65 (2)	2.511 (2)	174 (4)
O9—H9o···O4ⁱⁱ	0.86 (2)	1.87 (2)	2.728 (2)	175 (2)
N1—H1n···O4	0.86 (2)	1.94 (2)	2.802 (2)	173 (3)
N2—H2n···O2ⁱⁱⁱ	0.87 (2)	2.11 (2)	2.771 (2)	133 (2)

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

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