2-Methyl­imidazolium hydrogen maleate

Liu, Z.-X.

doi:10.1107/S1600536809004103

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 65| Part 3| March 2009| Page o499

doi:10.1107/S1600536809004103

Open

access

2-Methylimidazolium hydrogen maleate

Zhi-Xiong Liu ^a ^*

^aCollege of Horticulture and Gardening, Yangtze University, Jingzhou 434025, Hubei, People's Republic of China, and College of Biological Science and Biotechnology, Beijing Forestry University, Beijing 100083, People's Republic of China
^*Correspondence e-mail: zxliu1977@yahoo.com.cn

(Received 31 January 2009; accepted 4 February 2009; online 11 February 2009)

Molecules in the title compound, C₄H₇N₂⁺·C₄H₃O₄⁻, are linked by intermolecular N—H⋯O hydrogen bonds into one-dimensional chains parallel to [101]. These chains are in turn linked by an R₂²(8) motif, formed by weak C—H⋯O hydrogen bonds, into corrugated sheets running parallel to (10 $[\overline{1}]$ ). These sheets are further linked by weak intermolecular C—H⋯O hydrogen bonds, forming a three-dimensional network. Intramolecular N—H⋯O and O—H⋯O interactions are also present.

Related literature

For related structures, see: Aakeröy & Salmon (2005 ); Liu & Meng (2006 ). For hydrogen-bond motifs, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₄H₇N₂⁺·C₄H₃O₄⁻
M_r = 198.18
Monoclinic, C 2/c
a = 13.9897 (14) Å
b = 7.2274 (7) Å
c = 20.533 (2) Å
β = 108.310 (2)°
V = 1970.9 (3) Å³
Z = 8
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 295 (2) K
0.10 × 0.10 × 0.08 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2001 ) T_min = 0.979, T_max = 0.991
7461 measured reflections
2143 independent reflections
1273 reflections with I > 2σ(I)
R_int = 0.027

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.130
S = 0.99
2143 reflections
137 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.17 e Å⁻³
Δρ_min = −0.13 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H3A⋯O3	1.20 (3)	1.21 (3)	2.4085 (18)	174 (2)
N1—H1⋯O2	0.901 (19)	1.80 (2)	2.701 (2)	176.3 (17)
N2—H2A⋯O4ⁱ	0.95 (2)	1.77 (2)	2.713 (2)	171.2 (17)
C3—H3⋯O3ⁱⁱ	0.93	2.64	3.471 (2)	150
C4—H4A⋯O3ⁱ	0.96	2.59	3.490 (2)	155
C6—H6⋯O2ⁱⁱⁱ	0.93	2.66	3.544 (2)	158
Symmetry codes: (i) $[x+{\script{1\over 2}}, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ ; (ii) -x+1, -y+1, -z+1; (iii) $[-x+{\script{3\over 2}}, -y+{\script{5\over 2}}, -z+1]$ .

Data collection: SMART (Bruker, 2001 ); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003 ); software used to prepare material for publication: PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809004103/lh2769sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809004103/lh2769Isup2.hkl

checkCIF report

Comment top

As part of the continuing studies on the synthesis of co-crystal or organic salts involving imidazole (Liu & Meng, 2006), the crystal structure of title compound (I) is reported. It was obtained by mixing a 2:1 molar amounts of 2-methylimidazole and 2-maleic acid and in 95% methanol solution at room temperature.

According to Aakeröy and Salmon (2005) complex (I) is an organic salt. In (I), one of the carboxyl protons is transferred to the imidazole N atom, forming a 1:1 anhydrous organic adduct. The two carboxyl groups in the maleate anion are hydrogen-bonded to each other via atom H3A located approximately at the mid-point of atoms O1 and O3 (Fig.1).

In the crystal structure, by a combination of N1-H1···O2, N2-H2A···O4ⁱ and C4-H4A···O3ⁱ hydrogen bonds (symmetry codes as in Table 1) molecules in (I) are linked into a one-dimensional chain parallel to the [101] direction (Fig.2). These adjacent chains are linked by a R₂²(8) hydrogen motif (Bernstein et al., 1995) originating from two weak centrosymmetric C6-H6···O2 (3/2-x, 5/2-y, 1-z) hydrogen bonds, into a corrugated sheet running parallel to the (101) plane (Fig.3). These sheets are further linked by weak C3-H3···O3 (1-x, 1-y, 1-z) hydrogen bonds, forming a three-dimensional network.

Related literature top

For related structures, see: Aakeröy & Salmon (2005); Liu & Meng (2006). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

All the reagents and solvents were used as obtained without further purification. A 1:2 molar amounts of maleic acid (0.1 mmol, 11.6 mg) and 2-methylimidazole (0.2 mmol, 16.4 mg) were dissolved in 95% methanol (10 ml). The mixture was stirred for half an hour at room temperature and then filtered. The resulting solution was kept in air for one week. Block-shaped crystals suitable for single-crystal X-ray diffraction analysis were grown by slow evaporation of a solution of (I).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: PLATON (Spek, 2003).

Figures top

	Fig. 1. Molecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H-bonds are shown in dashed lines.
	Fig. 2. Part of the crystal structure of (I), showing the formation of the one-dimensional chain linked by intermolecular N-H···O hydrogen bonds parallel to the [101] direction. (symmetry code: i = 1/2+x, 3/2-y, 1/2+z)
	Fig. 3. Part of the crystal structure of (I), showing the formation of the two-dimensional corrugated sheet linked by intermolecular N-H···O and C-H···O hydrogen bonds (a) view perpendicular to the (101) plane and (b) view along to the (101) plane, respectively. Only H atoms involved in hydrogen bonds are shown.

2-Methylimidazolium hydrogen maleate top

Crystal data top

C₄H₇N₂⁺·C₄H₃O₄⁻	F(000) = 832
M_r = 198.18	D_x = 1.336 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 1457 reflections
a = 13.9897 (14) Å	θ = 3.1–21.4°
b = 7.2274 (7) Å	µ = 0.11 mm⁻¹
c = 20.533 (2) Å	T = 295 K
β = 108.310 (2)°	Block, colorless
V = 1970.9 (3) Å³	0.10 × 0.10 × 0.08 mm
Z = 8

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	2143 independent reflections
Radiation source: fine focus sealed Siemens Mo tube	1273 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.027
0.3° wide ω exposures scans	θ_max = 27.0°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 2001)	h = −17→17
T_min = 0.979, T_max = 0.991	k = −9→9
7461 measured reflections	l = −26→24

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.130	H atoms treated by a mixture of independent and constrained refinement
S = 0.99	w = 1/[σ²(F_o²) + (0.0703P)²] where P = (F_o² + 2F_c²)/3
2143 reflections	(Δ/σ)_max = 0.001
137 parameters	Δρ_max = 0.17 e Å⁻³
0 restraints	Δρ_min = −0.13 e Å⁻³

Crystal data top

C₄H₇N₂⁺·C₄H₃O₄⁻	V = 1970.9 (3) Å³
M_r = 198.18	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 13.9897 (14) Å	µ = 0.11 mm⁻¹
b = 7.2274 (7) Å	T = 295 K
c = 20.533 (2) Å	0.10 × 0.10 × 0.08 mm
β = 108.310 (2)°

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	2143 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2001)	1273 reflections with I > 2σ(I)
T_min = 0.979, T_max = 0.991	R_int = 0.027
7461 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	0 restraints
wR(F²) = 0.130	H atoms treated by a mixture of independent and constrained refinement
S = 0.99	Δρ_max = 0.17 e Å⁻³
2143 reflections	Δρ_min = −0.13 e Å⁻³
137 parameters

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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

	x	y	z	U_iso*/U_eq
C1	0.77143 (12)	0.6738 (2)	0.65115 (8)	0.0603 (4)
C2	0.64878 (15)	0.5430 (3)	0.57064 (11)	0.0810 (6)
H2	0.5957	0.5264	0.5303	0.097*
C3	0.68665 (14)	0.4163 (3)	0.61863 (11)	0.0812 (6)
H3	0.6654	0.2943	0.6183	0.097*
C4	0.84501 (15)	0.8105 (3)	0.69038 (10)	0.0855 (6)
H4A	0.8699	0.7731	0.7376	0.128*
H4B	0.8131	0.9293	0.6872	0.128*
H4C	0.9000	0.8183	0.6720	0.128*
C5	0.61393 (13)	1.0269 (2)	0.46763 (9)	0.0630 (5)
C6	0.59800 (13)	1.1982 (2)	0.42603 (9)	0.0641 (5)
H6	0.6446	1.2915	0.4440	0.077*
C7	0.52819 (11)	1.2406 (2)	0.36726 (9)	0.0643 (5)
H7	0.5327	1.3601	0.3517	0.077*
C8	0.44457 (13)	1.1297 (3)	0.32255 (9)	0.0652 (5)
N1	0.70226 (11)	0.7022 (2)	0.59149 (8)	0.0687 (4)
H1	0.6924 (14)	0.811 (3)	0.5686 (9)	0.082*
N2	0.76299 (11)	0.4998 (2)	0.66877 (8)	0.0665 (4)
H2A	0.8074 (14)	0.439 (3)	0.7076 (10)	0.080*
O1	0.55899 (10)	0.88414 (17)	0.44508 (7)	0.0830 (4)
O2	0.68111 (10)	1.02685 (18)	0.52321 (7)	0.0844 (4)
O3	0.43419 (11)	0.96097 (18)	0.33767 (7)	0.0885 (5)
H3A	0.495 (2)	0.916 (3)	0.3917 (15)	0.133*
O4	0.38675 (9)	1.20541 (19)	0.27165 (6)	0.0826 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0574 (10)	0.0627 (11)	0.0610 (10)	0.0021 (8)	0.0187 (8)	−0.0008 (8)
C2	0.0663 (11)	0.0887 (15)	0.0787 (13)	−0.0016 (10)	0.0093 (10)	−0.0184 (11)
C3	0.0727 (12)	0.0667 (12)	0.0994 (15)	−0.0082 (10)	0.0202 (11)	−0.0139 (11)
C4	0.0861 (13)	0.0770 (14)	0.0872 (14)	−0.0151 (10)	0.0186 (11)	−0.0040 (10)
C5	0.0611 (10)	0.0644 (11)	0.0618 (11)	−0.0024 (8)	0.0169 (9)	−0.0047 (8)
C6	0.0662 (10)	0.0583 (10)	0.0644 (11)	−0.0138 (8)	0.0158 (9)	−0.0052 (8)
C7	0.0649 (10)	0.0580 (10)	0.0660 (11)	−0.0100 (8)	0.0147 (9)	−0.0006 (8)
C8	0.0631 (11)	0.0734 (12)	0.0588 (11)	−0.0047 (9)	0.0188 (9)	−0.0052 (9)
N1	0.0679 (9)	0.0715 (10)	0.0631 (9)	0.0079 (8)	0.0154 (8)	0.0042 (7)
N2	0.0633 (9)	0.0610 (9)	0.0712 (10)	0.0041 (7)	0.0156 (8)	0.0035 (7)
O1	0.0929 (9)	0.0625 (8)	0.0787 (9)	−0.0138 (7)	0.0056 (8)	0.0039 (6)
O2	0.0830 (9)	0.0878 (10)	0.0658 (8)	−0.0080 (7)	−0.0005 (7)	0.0060 (6)
O3	0.0962 (10)	0.0716 (9)	0.0768 (9)	−0.0281 (7)	−0.0028 (7)	−0.0017 (7)
O4	0.0748 (8)	0.0894 (9)	0.0693 (8)	−0.0015 (7)	0.0021 (7)	0.0008 (7)

Geometric parameters (Å, º) top

C1—N1	1.317 (2)	C5—O1	1.283 (2)
C1—N2	1.324 (2)	C5—C6	1.481 (2)
C1—C4	1.471 (2)	C6—C7	1.328 (2)
C2—C3	1.327 (3)	C6—H6	0.9300
C2—N1	1.366 (2)	C7—C8	1.476 (2)
C2—H2	0.9300	C7—H7	0.9300
C3—N2	1.369 (2)	C8—O4	1.2307 (19)
C3—H3	0.9300	C8—O3	1.278 (2)
C4—H4A	0.9600	N1—H1	0.901 (19)
C4—H4B	0.9600	N2—H2A	0.95 (2)
C4—H4C	0.9600	O1—H3A	1.20 (3)
C5—O2	1.230 (2)	O3—H3A	1.21 (3)

N1—C1—N2	107.46 (16)	C7—C6—C5	130.67 (15)
N1—C1—C4	125.99 (16)	C7—C6—H6	114.7
N2—C1—C4	126.55 (16)	C5—C6—H6	114.7
C3—C2—N1	107.26 (17)	C6—C7—C8	130.74 (16)
C3—C2—H2	126.4	C6—C7—H7	114.6
N1—C2—H2	126.4	C8—C7—H7	114.6
C2—C3—N2	106.84 (18)	O4—C8—O3	122.41 (17)
C2—C3—H3	126.6	O4—C8—C7	117.90 (17)
N2—C3—H3	126.6	O3—C8—C7	119.69 (16)
C1—C4—H4A	109.5	C1—N1—C2	109.26 (16)
C1—C4—H4B	109.5	C1—N1—H1	124.6 (12)
H4A—C4—H4B	109.5	C2—N1—H1	126.1 (12)
C1—C4—H4C	109.5	C1—N2—C3	109.18 (16)
H4A—C4—H4C	109.5	C1—N2—H2A	125.4 (11)
H4B—C4—H4C	109.5	C3—N2—H2A	125.1 (11)
O2—C5—O1	122.12 (17)	C5—O1—H3A	111.7 (11)
O2—C5—C6	117.90 (15)	C5—O2—H1	113.4 (6)
O1—C5—C6	119.98 (16)	C8—O3—H3A	112.4 (11)

N1—C2—C3—N2	0.3 (2)	C4—C1—N1—C2	179.34 (16)
O2—C5—C6—C7	−175.16 (18)	C3—C2—N1—C1	−0.1 (2)
O1—C5—C6—C7	5.4 (3)	N1—C1—N2—C3	0.27 (19)
C5—C6—C7—C8	−1.9 (3)	C4—C1—N2—C3	−179.18 (16)
C6—C7—C8—O4	176.67 (17)	C2—C3—N2—C1	−0.3 (2)
C6—C7—C8—O3	−3.0 (3)	O1—C5—O2—H1	−0.7 (7)
N2—C1—N1—C2	−0.11 (19)	C6—C5—O2—H1	179.9 (6)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H3A···O3	1.20 (3)	1.21 (3)	2.4085 (18)	174 (2)
N1—H1···O2	0.901 (19)	1.80 (2)	2.701 (2)	176.3 (17)
N2—H2A···O4ⁱ	0.95 (2)	1.77 (2)	2.713 (2)	171.2 (17)
C3—H3···O3ⁱⁱ	0.93	2.64	3.471 (2)	150
C4—H4A···O3ⁱ	0.96	2.59	3.490 (2)	155
C6—H6···O2ⁱⁱⁱ	0.93	2.66	3.544 (2)	158

Symmetry codes: (i) x+1/2, −y+3/2, z+1/2; (ii) −x+1, −y+1, −z+1; (iii) −x+3/2, −y+5/2, −z+1.

Experimental details

Crystal data
Chemical formula	C₄H₇N₂⁺·C₄H₃O₄⁻
M_r	198.18
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	295
a, b, c (Å)	13.9897 (14), 7.2274 (7), 20.533 (2)
β (°)	108.310 (2)
V (Å³)	1970.9 (3)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.10 × 0.10 × 0.08

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2001)
T_min, T_max	0.979, 0.991
No. of measured, independent and observed [I > 2σ(I)] reflections	7461, 2143, 1273
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.130, 0.99
No. of reflections	2143
No. of parameters	137
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.17, −0.13

Computer programs: SMART (Bruker, 2001), SAINT-Plus (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H3A···O3	1.20 (3)	1.21 (3)	2.4085 (18)	174 (2)
N1—H1···O2	0.901 (19)	1.80 (2)	2.701 (2)	176.3 (17)
N2—H2A···O4ⁱ	0.95 (2)	1.77 (2)	2.713 (2)	171.2 (17)
C3—H3···O3ⁱⁱ	0.93	2.64	3.471 (2)	150
C4—H4A···O3ⁱ	0.96	2.59	3.490 (2)	155
C6—H6···O2ⁱⁱⁱ	0.93	2.66	3.544 (2)	158

Symmetry codes: (i) x+1/2, −y+3/2, z+1/2; (ii) −x+1, −y+1, −z+1; (iii) −x+3/2, −y+5/2, −z+1.

Acknowledgements

This work received financial support mainly from Yangtze University.

References

Aakeröy, C. B. & Salmon, D. J. (2005). CrystEngComm, 7, 439–448. Web of Science CrossRef Google Scholar
Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573. CrossRef CAS Web of Science Google Scholar
Bruker (2001). SAINT-Plus and SMART. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Liu, Z.-X. & Meng, X.-G. (2006). Acta Cryst. E62, o1286–o1288. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2001). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2003). J. Appl. Cryst. 36, 7–13. Web of Science CrossRef CAS IUCr Journals Google Scholar