organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

5-Carb­­oxy-1,3-bis­­(carb­­oxy­meth­yl)-4-imidazolinium-4-carboxyl­ate

aCollege of Chemistry and Chemical Engineering, Key Laboratory of Eco-Environment-Related Polymer Materials of the Ministry of Education, Gansu Key Laboratory of Polymer Materials, Northwest Normal University, Lanzhou 730070, People's Republic of China
*Correspondence e-mail: weitaibao@126.com

(Received 9 December 2011; accepted 16 December 2011; online 23 December 2011)

The title compound, C9H8N2O8, was obtained by the reaction of imidazole-4,5-dicarb­oxy­lic acid and 2-chloro­acetic acid. An intra­molecular O—H⋯O hydrogen bond occurs. The crystal packing is stabilized by intermolecular O—H⋯O and C—H⋯O hydrogen bonds, which link mol­ecules into a three-dimensional network.

Related literature

The title compound is a potential polydentate ligand for the construction of metal-organic frameworks. For applications of metal-organic frameworks, see: Gao et al. (2005[Gao, S., Huo, L.-H., Zhao, H. & Liu, J.-W. (2005). Acta Cryst. E61, m155-m157.]); Gurunatha et al. (2008[Gurunatha, K.-L., Kazuhiro, U. & Tapas, K.-M. (2008). Inorg. Chem. pp. 6578-6580.]); Wang et al. (2010[Wang, X.-J., Cen, Z.-M. & Ni, Q.-L. (2010). Cryst. Growth Des. 16, 1613-1618.]); Zhang & Li (2010[Zhang, F.-W. & Li, Z.-F. (2010). Inorg. Chem. 49, 3776-3788.]). For related structures, see: Chai et al. (2010[Chai, X.-C., Sun, Y.-Q. & Lei, R. (2010). Cryst. Growth Des. 10, 658-668.]); Liu et al. (2004[Liu, J.-W., Gao, S., Huo, L.-H., Gu, C.-S., Zhao, H. & Zhao, J.-G. (2004). Acta Cryst. E60, m1697-m1699.]); Lu et al. (2006[Lu, W.-G., Jiang, L., Feng, X.-L. & Lu, T. B. (2006). Cryst. Growth Des. 14, 564-571.]).

[Scheme 1]

Experimental

Crystal data
  • C9H8N2O8

  • Mr = 272.17

  • Orthorhombic, P b c a

  • a = 8.986 (7) Å

  • b = 7.041 (6) Å

  • c = 33.68 (3) Å

  • V = 2131 (3) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.15 mm−1

  • T = 296 K

  • 0.35 × 0.33 × 0.29 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). SAINT, APEX2 and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.948, Tmax = 0.957

  • 13878 measured reflections

  • 2091 independent reflections

  • 1750 reflections with I2s(I)

  • Rint = 0.055

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.109

  • S = 0.98

  • 2091 reflections

  • 185 parameters

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

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3—H3W⋯O2 1.13 (3) 1.29 (3) 2.426 (3) 177 (3)
C1—H1⋯O6i 0.93 2.47 3.158 (3) 131
C4—H4A⋯O5ii 0.97 2.38 3.311 (3) 160
C4—H4B⋯O6i 0.97 2.37 3.046 (3) 126
C6—H6A⋯O7i 0.97 2.42 3.136 (4) 130
C6—H6B⋯O8iii 0.97 2.44 3.346 (3) 154
O5—H2W⋯O1iv 0.92 (3) 1.67 (3) 2.581 (3) 170 (3)
O8—H1W⋯O4v 0.93 (4) 1.84 (4) 2.710 (3) 155 (3)
Symmetry codes: (i) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, z]; (ii) [x-{\script{1\over 2}}, y, -z+{\script{1\over 2}}]; (iii) -x, -y, -z+1; (iv) [-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (v) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1].

Data collection: APEX2 (Bruker, 2008[Bruker (2008). SAINT, APEX2 and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). SAINT, APEX2 and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

In recent years, increasing attention has been paid to the imidazole carboxylate ligands such as imidazole-4,5-dicarboxylic acid (H3IDC), (Gao et al., 2005; Gurunatha et al., 2008) and 1,3-dicarboxymethyl acid imidazolium (HDAM), (Wang et al., 2010; Zhang et al., 2010). H3IDC has six potential donor atoms (4O, 2 N) and can be partially or fully deprotonated to generate H2IDC-, HIDC2- and IDC3- anions at different pH values. Therefore, it can coordinate with metal ions in multi-coordinated ways to form a large diversity of supramolecular architectures (Lu et al., 2006; Liu et al., 2004). The zwitterionic dicarboxylate ligand HDAM, due to the presence of –CH2– spacers between the imidazole and carboxylate groups, has many degrees of flexibility and conformational freedom by bending or rotation when coordinating to the metal centre to give entanglements, conformational polymorphism and supramolecular isomerism, which may provide more possibility for the construction of unprecedented connected topological frameworks (Chai et al., 2010). Taking the above into consideration, we designed and synthesized the title compound (H3DDAM) as a novel ligand, and its molecular structure is reported herein.

The molecular structure of the title compound is shown in Fig. 1. The values of the C–O bond length within the carboxylic groups in 4- and 5-position of the imidazole ring range from 1.216 (3) to 1.295 (3), suggesting a delocalization of the negative charge within the two groups. As a consequence, the H3W proton is nearly symmetrically shared by the O2 and O3 oxygen atoms. The O1/O2/C8 and O3/O4/C9 carboxylic groups are approximately co-planar with the imidazole ring (dihedral angles 9.02 (14) and 10.37 (13)°, respectively), whereas the O5/O6/C5 and O7/O8/C7 groups are almost perpendicular, forming dihedral angles of 80.2 (2) and 88.1 (2)°, respectively. In the crystal structure, intermolecular O—H···O and C—H···O hydrogen bonds (Table 1) link molecules into a three-dimensional network.

Related literature top

The title compound is a potential polydentate ligand for the construction of metal-organic frameworks. For applications of metal-organic frameworks, see: Gao et al. (2005); Gurunatha et al. (2008); Wang et al. (2010); Zhang et al. (2010). For related structures, see: Chai et al. (2010); Liu et al. (2004); Lu et al. (2006).

Experimental top

Imidazole-4, 5-dicarboxylic acid (1.56 g, 0.01 mol) was slowly added to the stirred aqueous solution of 2-chloroacetic acid (2.82 g, 0.03 mol) and sodium hydroxide (1.2 g, 0.12 mol) in 30 ml of distilled water. The mixture was stirred for ca 4 h at reflux temperature, and the pH of the solution was controlled in the range of 8–11 with 5 M NaOH solution. Aqueous HCl (12M) was poured into the resultant mixture until the pH was 2–3. After cooling to room temperature, red block crystals suitable for X-ray structure analysis were obtained (2.28 g, yield: 83.7%). M.p.: 234–236 °C. Anal. Calcd for H3DDAM: C, 39.68; H, 2.94; N, 10.29, Found: C, 39.61; H, 2.98; N, 10.22.

Refinement top

The carboxylic H atoms were located in a difference Fourier map and refined freely. All other H atoms were included in calculated positions and refined in a riding-model approximation with C—H distances ranging from 0.93 to 0.97Å and Uiso(H) = 1.2 Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The structure of the title compound, showing the atom labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
5-Carboxy-1,3-bis(carboxymethyl)-4-imidazolinium-4-carboxylate top
Crystal data top
C9H8N2O8Dx = 1.697 Mg m3
Mr = 272.17Melting point: 510 K
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 5190 reflections
a = 8.986 (7) Åθ = 2.4–27.8°
b = 7.041 (6) ŵ = 0.15 mm1
c = 33.68 (3) ÅT = 296 K
V = 2131 (3) Å3Block, red
Z = 80.35 × 0.33 × 0.29 mm
F(000) = 1120
Data collection top
Bruker APEXII CCD
diffractometer
2091 independent reflections
Radiation source: fine-focus sealed tube1750 reflections with I2s(I)
Graphite monochromatorRint = 0.055
ϕ and ω scansθmax = 26.0°, θmin = 2.4°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 1111
Tmin = 0.948, Tmax = 0.957k = 88
13878 measured reflectionsl = 4041
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.048H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.109 w = 1/[σ2(Fo2) + (0.0398P)2 + 2.3475P]
where P = (Fo2 + 2Fc2)/3
S = 0.98(Δ/σ)max < 0.001
2091 reflectionsΔρmax = 0.23 e Å3
185 parametersΔρmin = 0.19 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.065 (3)
Crystal data top
C9H8N2O8V = 2131 (3) Å3
Mr = 272.17Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 8.986 (7) ŵ = 0.15 mm1
b = 7.041 (6) ÅT = 296 K
c = 33.68 (3) Å0.35 × 0.33 × 0.29 mm
Data collection top
Bruker APEXII CCD
diffractometer
2091 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
1750 reflections with I2s(I)
Tmin = 0.948, Tmax = 0.957Rint = 0.055
13878 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0480 restraints
wR(F2) = 0.109H atoms treated by a mixture of independent and constrained refinement
S = 0.98Δρmax = 0.23 e Å3
2091 reflectionsΔρmin = 0.19 e Å3
185 parameters
Special details top

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 (Å2) top
xyzUiso*/Ueq
C10.0333 (2)0.0455 (3)0.36566 (6)0.0294 (5)
H10.06830.07680.36100.035*
C20.0421 (2)0.3049 (3)0.39610 (6)0.0259 (5)
C30.0421 (2)0.3386 (3)0.35616 (6)0.0254 (5)
C40.0345 (2)0.1384 (3)0.29562 (6)0.0298 (5)
H4A0.04530.19040.27960.036*
H4B0.04060.00300.29060.036*
C50.1801 (3)0.2329 (3)0.28505 (6)0.0347 (5)
C60.0369 (2)0.0165 (3)0.43809 (6)0.0309 (5)
H6A0.02730.11920.43380.037*
H6B0.03390.05370.45840.037*
C70.1931 (3)0.0624 (3)0.45163 (6)0.0322 (5)
C80.0809 (2)0.5139 (3)0.33270 (6)0.0312 (5)
C90.0854 (2)0.4261 (3)0.43069 (6)0.0311 (5)
N10.00421 (19)0.1725 (2)0.33789 (5)0.0266 (4)
N20.00520 (19)0.1186 (2)0.40108 (5)0.0267 (4)
O10.0529 (2)0.5150 (2)0.29686 (4)0.0433 (5)
O20.1404 (2)0.6492 (2)0.35153 (5)0.0467 (5)
O30.1520 (2)0.5842 (2)0.42221 (5)0.0436 (5)
O40.0606 (2)0.3734 (2)0.46442 (4)0.0417 (4)
O50.2115 (2)0.2377 (3)0.24692 (5)0.0528 (6)
O60.2616 (2)0.2993 (3)0.30957 (5)0.0522 (5)
O70.28441 (18)0.1355 (3)0.43067 (5)0.0459 (5)
O80.2134 (2)0.0069 (3)0.48852 (5)0.0479 (5)
H2W0.149 (4)0.170 (5)0.2306 (9)0.075 (10)*
H1W0.306 (4)0.045 (5)0.4978 (10)0.082 (11)*
H3W0.149 (4)0.617 (4)0.3891 (9)0.073 (9)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0302 (11)0.0273 (11)0.0306 (11)0.0000 (9)0.0007 (9)0.0047 (9)
C20.0233 (10)0.0260 (10)0.0285 (10)0.0003 (8)0.0004 (8)0.0012 (8)
C30.0234 (10)0.0266 (10)0.0261 (10)0.0016 (8)0.0002 (8)0.0027 (8)
C40.0333 (12)0.0328 (11)0.0234 (10)0.0017 (10)0.0005 (8)0.0077 (9)
C50.0314 (12)0.0384 (12)0.0343 (12)0.0035 (10)0.0044 (9)0.0126 (10)
C60.0355 (12)0.0286 (11)0.0286 (11)0.0000 (9)0.0000 (9)0.0057 (9)
C70.0398 (13)0.0273 (11)0.0294 (11)0.0014 (10)0.0019 (10)0.0004 (9)
C80.0317 (12)0.0322 (12)0.0296 (11)0.0003 (10)0.0018 (9)0.0019 (9)
C90.0301 (11)0.0343 (12)0.0290 (11)0.0012 (10)0.0036 (9)0.0052 (9)
N10.0282 (9)0.0283 (9)0.0234 (9)0.0004 (8)0.0012 (7)0.0043 (7)
N20.0298 (9)0.0264 (9)0.0240 (8)0.0006 (8)0.0001 (7)0.0002 (7)
O10.0579 (11)0.0434 (10)0.0286 (8)0.0069 (8)0.0023 (7)0.0058 (7)
O20.0662 (12)0.0343 (9)0.0397 (9)0.0182 (9)0.0040 (8)0.0020 (8)
O30.0539 (11)0.0401 (10)0.0368 (9)0.0166 (8)0.0043 (8)0.0083 (7)
O40.0550 (11)0.0451 (10)0.0249 (8)0.0022 (9)0.0033 (7)0.0049 (7)
O50.0522 (12)0.0692 (13)0.0370 (9)0.0241 (10)0.0166 (8)0.0153 (9)
O60.0413 (10)0.0652 (13)0.0501 (10)0.0177 (9)0.0020 (8)0.0202 (9)
O70.0388 (10)0.0537 (11)0.0452 (10)0.0106 (9)0.0016 (8)0.0126 (9)
O80.0497 (11)0.0645 (12)0.0296 (9)0.0099 (10)0.0091 (8)0.0080 (8)
Geometric parameters (Å, º) top
C1—N11.320 (3)C6—N21.467 (3)
C1—N21.324 (3)C6—C71.511 (3)
C1—H10.9300C6—H6A0.9700
C2—C31.366 (3)C6—H6B0.9700
C2—N21.389 (3)C7—O71.199 (3)
C2—C91.496 (3)C7—O81.316 (3)
C3—N11.385 (3)C8—O11.233 (3)
C3—C81.506 (3)C8—O21.263 (3)
C4—N11.469 (3)C9—O41.216 (3)
C4—C51.511 (3)C9—O31.295 (3)
C4—H4A0.9700O2—H3W1.29 (3)
C4—H4B0.9700O3—H3W1.14 (3)
C5—O61.199 (3)O5—H2W0.92 (3)
C5—O51.315 (3)O8—H1W0.93 (4)
N1—C1—N2109.72 (19)C7—C6—H6B109.8
N1—C1—H1125.1H6A—C6—H6B108.2
N2—C1—H1125.1O7—C7—O8126.1 (2)
C3—C2—N2106.45 (17)O7—C7—C6123.4 (2)
C3—C2—C9131.9 (2)O8—C7—C6110.53 (19)
N2—C2—C9121.62 (19)O1—C8—O2125.0 (2)
C2—C3—N1106.91 (18)O1—C8—C3118.1 (2)
C2—C3—C8131.23 (19)O2—C8—C3116.90 (19)
N1—C3—C8121.86 (18)O4—C9—O3123.6 (2)
N1—C4—C5108.45 (17)O4—C9—C2120.4 (2)
N1—C4—H4A110.0O3—C9—C2116.01 (19)
C5—C4—H4A110.0C1—N1—C3108.44 (18)
N1—C4—H4B110.0C1—N1—C4122.60 (18)
C5—C4—H4B110.0C3—N1—C4128.64 (17)
H4A—C4—H4B108.4C1—N2—C2108.46 (18)
O6—C5—O5122.1 (2)C1—N2—C6122.56 (19)
O6—C5—C4122.6 (2)C2—N2—C6128.68 (17)
O5—C5—C4115.28 (19)C8—O2—H3W112.5 (14)
N2—C6—C7109.38 (17)C9—O3—H3W112.0 (16)
N2—C6—H6A109.8C5—O5—H2W116 (2)
C7—C6—H6A109.8C7—O8—H1W111 (2)
N2—C6—H6B109.8
N2—C2—C3—N10.3 (2)N2—C1—N1—C31.4 (2)
C9—C2—C3—N1177.8 (2)N2—C1—N1—C4175.52 (18)
N2—C2—C3—C8179.3 (2)C2—C3—N1—C11.1 (2)
C9—C2—C3—C82.5 (4)C8—C3—N1—C1178.64 (18)
N1—C4—C5—O69.2 (3)C2—C3—N1—C4174.69 (19)
N1—C4—C5—O5170.7 (2)C8—C3—N1—C45.0 (3)
N2—C6—C7—O715.1 (3)C5—C4—N1—C198.9 (2)
N2—C6—C7—O8166.48 (18)C5—C4—N1—C374.0 (3)
C2—C3—C8—O1170.6 (2)N1—C1—N2—C21.2 (2)
N1—C3—C8—O19.0 (3)N1—C1—N2—C6175.48 (18)
C2—C3—C8—O29.5 (3)C3—C2—N2—C10.5 (2)
N1—C3—C8—O2170.9 (2)C9—C2—N2—C1178.88 (18)
C3—C2—C9—O4171.7 (2)C3—C2—N2—C6174.33 (19)
N2—C2—C9—O410.4 (3)C9—C2—N2—C67.3 (3)
C3—C2—C9—O39.6 (3)C7—C6—N2—C190.0 (2)
N2—C2—C9—O3168.3 (2)C7—C6—N2—C283.1 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3W···O21.13 (3)1.29 (3)2.426 (3)177 (3)
C1—H1···O6i0.932.473.158 (3)131
C4—H4A···O5ii0.972.383.311 (3)160
C4—H4B···O6i0.972.373.046 (3)126
C6—H6A···O7i0.972.423.136 (4)130
C6—H6B···O8iii0.972.443.346 (3)154
O5—H2W···O1iv0.92 (3)1.67 (3)2.581 (3)170 (3)
O8—H1W···O4v0.93 (4)1.84 (4)2.710 (3)155 (3)
Symmetry codes: (i) x+1/2, y1/2, z; (ii) x1/2, y, z+1/2; (iii) x, y, z+1; (iv) x, y1/2, z+1/2; (v) x+1/2, y+1/2, z+1.

Experimental details

Crystal data
Chemical formulaC9H8N2O8
Mr272.17
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)296
a, b, c (Å)8.986 (7), 7.041 (6), 33.68 (3)
V3)2131 (3)
Z8
Radiation typeMo Kα
µ (mm1)0.15
Crystal size (mm)0.35 × 0.33 × 0.29
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.948, 0.957
No. of measured, independent and
observed [I2s(I)] reflections
13878, 2091, 1750
Rint0.055
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.109, 0.98
No. of reflections2091
No. of parameters185
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.23, 0.19

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SAINT (Bruker, 2008, SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3W···O21.13 (3)1.29 (3)2.426 (3)177 (3)
C1—H1···O6i0.932.473.158 (3)131
C4—H4A···O5ii0.972.383.311 (3)160
C4—H4B···O6i0.972.373.046 (3)126
C6—H6A···O7i0.972.423.136 (4)130
C6—H6B···O8iii0.972.443.346 (3)154
O5—H2W···O1iv0.92 (3)1.67 (3)2.581 (3)170 (3)
O8—H1W···O4v0.93 (4)1.84 (4)2.710 (3)155 (3)
Symmetry codes: (i) x+1/2, y1/2, z; (ii) x1/2, y, z+1/2; (iii) x, y, z+1; (iv) x, y1/2, z+1/2; (v) x+1/2, y+1/2, z+1.
 

Acknowledgements

This work was supported by the NSFC (No. 21064006) and the Natural Science Foundation of Gansu (1010RJZA018), which are gratefully acknowledged.

References

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