Diaqua­bis­(1H-imidazole-4-carboxyl­ato-κ² N ³,O ⁴)manganese(II)

Abstract

In the title compound, [Mn(C₄H₃N₂O₂)₂(H₂O)₂], the Mn^II ion is located on a twofold rotation axis and displays a distorted octa­hedral coordination environment, defined by two N,O-bidentate 1H-imidazole-4-carboxyl­ate ligands in the equatorial plane and two water mol­ecules in axial positions. In the crystal, O—H⋯O and N—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional supra­molecular network. π–π stacking inter­actions between the imidazole rings [centroid–centroid distances = 3.5188 (15) and 3.6687 (15) Å] further stabilize the structure.

Related literature  

For related structures, see: Cai et al. (2012 ▶); Chen (2012 ▶); Gryz et al. (2007 ▶); Haggag (2005 ▶); Shuai et al. (2011 ▶); Starosta & Leciejewicz (2006 ▶); Yin et al. (2009 ▶); Zheng et al. (2011 ▶).

Experimental  

Crystal data  

• [Mn(C₄H₃N₂O₂)₂(H₂O)₂]

• M _r = 313.14

• Orthorhombic,

• a = 7.3052 (10) Å

• b = 11.7997 (17) Å

• c = 13.5156 (19) Å

• V = 1165.0 (3) ų

• Z = 4

• Mo Kα radiation

• μ = 1.16 mm⁻¹

• T = 298 K

• 0.36 × 0.32 × 0.30 mm

Data collection  

• Bruker APEXII CCD diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 2001 ▶) T _min = 0.679, T _max = 0.721

• 5775 measured reflections

• 1145 independent reflections

• 972 reflections with I > 2σ(I)

• R _int = 0.067

Refinement  

• R[F ² > 2σ(F ²)] = 0.039

• wR(F ²) = 0.109

• S = 1.07

• 1145 reflections

• 87 parameters

• H-atom parameters constrained

• Δρ_max = 0.34 e Å⁻³

• Δρ_min = −0.57 e Å⁻³

Data collection: APEX2 (Bruker, 2007 ▶); cell refinement: SAINT (Bruker, 2007 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ▶) and PLATON (Spek, 2009 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2⋯O2i	0.86	1.95	2.811 (3)	173
O1W—H1WA⋯O2ii	0.87	1.96	2.818 (2)	167
O1W—H1WB⋯O2iii	0.73	2.02	2.751 (2)	176

Symmetry codes: (i) ; (ii) ; (iii) .

supplementary crystallographic information

Comment

In the past few years, structures containing metals and N-heterocyclic carboxylic acids have attracted much attention due to their fascinating structures and potential applications in many fields. 1H-Imidazole-4-carboxylic acid (H₂imc), which contains two N atoms of an imidazole group and one carboxylate group, has been widely used to prepare a variety of coordination polymers with different structures and exceptional properties (Cai et al., 2012; Gryz et al., 2007; Haggag, 2005; Starosta & Leciejewicz, 2006; Zheng et al., 2011). For instance, three mononuclear complexes, [Cd(Himc)₂(H₂O)₂] (Yin et al., 2009), [Zn(Himc)₂(H₂O)₂] (Shuai et al., 2011) and [Co(Himc)₂(H₂O)₂] (Chen, 2012), have been reported. In this paper, we report the synthesis and structure of a new Mn(II) coordination polymer, [Mn(Himc)₂(H₂O)₂], which is isomorphous with the Cd(II), Zn(II) and Co(II) analogs.

The asymmetric unit of the title compound contains a half of [Mn(Himc)₂(H₂O)₂] formula unit. The Mn^II ion, lying on a twofold rotation axis, is six-coordinated by two N and two O atoms from two cis-oriented N,O-bidentate Himc ligands in the equatorial plane, and two water molecules in the axial positions, forming a slightly distorted octahedral geometry (Fig. 1). The bond lengths and angles around the Mn atom are normal. In the crystal structure, intermolecular O—H···O and N—H···O hydrogen bonds (Table 1) involving the coordinated water O atoms, carboxylate O atoms and imidazole N atoms link the molecules into a three-dimensional supramolecular network, as presented in Fig. 2. π–π stacking interactions between the imidazole rings [centroid–centroid distances = 3.5188 (15) and 3.6687 (15) Å] further stabilize the crystal structure.

Experimental

A mixture of H₂imc (0.30 mmol), MnCl₂.6H₂O (0.30 mmol) and 6 ml EtOH/H₂O (v/v 1:1) was sealed into a 10 ml sample bottle reactor and heated at 373 k for 72 h under autogenous pressure, and then slowly cooled to room temperature at a rate of 5 K/h. Colorless block crystals of the title compound were obtained, washed with distilled water and dried in air (yield: 30%).

Refinement

C- and N-bound H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93 and N—H = 0.86 Å and with U_iso(H) = 1.2U_eq(C, N). H atoms of the water molecule were located from a difference Fourier map and refined as riding atoms, with U_iso(H) = 1.5U_eq(O).

Figures

Fig. 1.

The molecular structure of the title compound. Displacement ellipsoids are drawn at the 30% probability level. [Symmetry code: (i) -x+3/2, -y+3/2, z.]

Fig. 2.

The crystal packing of the title compound, showing the three-dimensional supramolecular network. Hydrogen bonds are shown as dashed lines.

Crystal data

[Mn(C4H3N2O2)2(H2O)2]	F(000) = 636
Mr = 313.14	Dx = 1.785 Mg m−3
Orthorhombic, Pccn	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ab 2ac	Cell parameters from 1516 reflections
a = 7.3052 (10) Å	θ = 3.3–24.9°
b = 11.7997 (17) Å	µ = 1.16 mm−1
c = 13.5156 (19) Å	T = 298 K
V = 1165.0 (3) Å3	Block, colourless
Z = 4	0.36 × 0.32 × 0.30 mm

Data collection

Bruker APEXII CCD diffractometer	1145 independent reflections
Radiation source: fine-focus sealed tube	972 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.067
φ and ω scans	θmax = 26.0°, θmin = 3.0°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −8→9
Tmin = 0.679, Tmax = 0.721	k = −14→10
5775 measured reflections	l = −16→15

Refinement

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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.109	H-atom parameters constrained
S = 1.07	w = 1/[σ2(Fo2) + (0.0489P)2 + 0.3284P] where P = (Fo2 + 2Fc2)/3
1145 reflections	(Δ/σ)max = 0.001
87 parameters	Δρmax = 0.34 e Å−3
0 restraints	Δρmin = −0.57 e Å−3

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
Mn1	0.7500	0.7500	0.63202 (3)	0.0256 (2)
N1	0.5501 (2)	0.81048 (17)	0.52125 (14)	0.0282 (5)
N2	0.3599 (3)	0.87066 (19)	0.40742 (14)	0.0342 (5)
H2	0.3136	0.8835	0.3500	0.041*
C1	0.4022 (3)	0.87462 (18)	0.67505 (16)	0.0238 (5)
C2	0.4063 (3)	0.86601 (18)	0.56583 (16)	0.0241 (5)
C4	0.5155 (3)	0.8144 (2)	0.42597 (17)	0.0350 (6)
H4	0.5895	0.7822	0.3775	0.042*
C3	0.2882 (4)	0.9039 (2)	0.49557 (18)	0.0312 (5)
H3	0.1804	0.9442	0.5057	0.037*
O1	0.5374 (2)	0.83532 (14)	0.72111 (11)	0.0310 (4)
O2	0.2642 (2)	0.91985 (15)	0.71532 (12)	0.0302 (4)
O1W	0.5981 (2)	0.59207 (14)	0.66084 (14)	0.0392 (5)
H1WA	0.6528	0.5466	0.7024	0.059*
H1WB	0.5022	0.5856	0.6758	0.059*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Mn1	0.0235 (4)	0.0344 (4)	0.0189 (3)	0.00646 (18)	0.000	0.000
N1	0.0272 (11)	0.0389 (12)	0.0184 (10)	0.0068 (8)	−0.0009 (8)	−0.0021 (8)
N2	0.0348 (13)	0.0490 (13)	0.0186 (10)	0.0037 (9)	−0.0074 (8)	0.0014 (8)
C1	0.0247 (12)	0.0233 (11)	0.0233 (12)	−0.0029 (9)	0.0020 (9)	−0.0011 (8)
C2	0.0243 (12)	0.0288 (12)	0.0192 (12)	0.0008 (9)	0.0002 (9)	−0.0007 (8)
C4	0.0359 (15)	0.0506 (16)	0.0186 (12)	0.0067 (11)	0.0000 (10)	−0.0031 (10)
C3	0.0289 (12)	0.0391 (13)	0.0256 (13)	0.0037 (10)	−0.0008 (10)	0.0009 (10)
O1	0.0287 (10)	0.0457 (10)	0.0186 (8)	0.0087 (7)	−0.0010 (7)	−0.0002 (7)
O2	0.0243 (10)	0.0432 (11)	0.0232 (10)	0.0047 (6)	0.0048 (6)	−0.0051 (7)
O1W	0.0279 (10)	0.0429 (11)	0.0467 (12)	0.0036 (7)	0.0039 (8)	0.0133 (8)

Geometric parameters (Å, º)

Mn1—O1W	2.2037 (17)	N2—H2	0.8600
Mn1—O1Wi	2.2038 (17)	C1—O1	1.257 (3)
Mn1—O1i	2.2079 (16)	C1—O2	1.264 (3)
Mn1—O1	2.2079 (16)	C1—C2	1.480 (3)
Mn1—N1	2.2097 (19)	C2—C3	1.359 (3)
Mn1—N1i	2.2097 (19)	C4—H4	0.9300
N1—C4	1.313 (3)	C3—H3	0.9300
N1—C2	1.377 (3)	O1W—H1WA	0.87
N2—C4	1.340 (3)	O1W—H1WB	0.73
N2—C3	1.359 (3)
O1W—Mn1—O1Wi	159.64 (10)	C4—N2—H2	126.1
O1W—Mn1—O1i	82.66 (6)	C3—N2—H2	126.1
O1Wi—Mn1—O1i	86.27 (6)	O1—C1—O2	124.7 (2)
O1W—Mn1—O1	86.27 (6)	O1—C1—C2	116.93 (18)
O1Wi—Mn1—O1	82.66 (6)	O2—C1—C2	118.34 (19)
O1i—Mn1—O1	113.90 (8)	C3—C2—N1	109.6 (2)
O1W—Mn1—N1	93.44 (7)	C3—C2—C1	131.4 (2)
O1Wi—Mn1—N1	100.34 (7)	N1—C2—C1	118.98 (18)
O1i—Mn1—N1	168.96 (6)	N1—C4—N2	111.4 (2)
O1—Mn1—N1	75.97 (7)	N1—C4—H4	124.3
O1W—Mn1—N1i	100.34 (7)	N2—C4—H4	124.3
O1Wi—Mn1—N1i	93.44 (7)	C2—C3—N2	105.9 (2)
O1i—Mn1—N1i	75.96 (7)	C2—C3—H3	127.1
O1—Mn1—N1i	168.97 (6)	N2—C3—H3	127.1
N1—Mn1—N1i	94.70 (10)	C1—O1—Mn1	116.82 (14)
C4—N1—C2	105.38 (19)	Mn1—O1W—H1WA	113.7
C4—N1—Mn1	143.43 (17)	Mn1—O1W—H1WB	128.2
C2—N1—Mn1	111.19 (14)	H1WA—O1W—H1WB	101.3
C4—N2—C3	107.8 (2)
O1W—Mn1—N1—C4	−95.6 (3)	O1—C1—C2—N1	3.7 (3)
O1Wi—Mn1—N1—C4	99.5 (3)	O2—C1—C2—N1	−175.9 (2)
O1i—Mn1—N1—C4	−26.7 (5)	C2—N1—C4—N2	1.0 (3)
O1—Mn1—N1—C4	179.1 (3)	Mn1—N1—C4—N2	−178.4 (2)
N1i—Mn1—N1—C4	5.1 (3)	C3—N2—C4—N1	−0.8 (3)
O1W—Mn1—N1—C2	85.01 (16)	N1—C2—C3—N2	0.3 (3)
O1Wi—Mn1—N1—C2	−79.94 (16)	C1—C2—C3—N2	−179.3 (2)
O1i—Mn1—N1—C2	153.9 (3)	C4—N2—C3—C2	0.3 (3)
O1—Mn1—N1—C2	−0.28 (15)	O2—C1—O1—Mn1	175.69 (16)
N1i—Mn1—N1—C2	−174.31 (19)	C2—C1—O1—Mn1	−3.9 (2)
C4—N1—C2—C3	−0.8 (3)	O1W—Mn1—O1—C1	−92.12 (16)
Mn1—N1—C2—C3	178.83 (16)	O1Wi—Mn1—O1—C1	105.01 (16)
C4—N1—C2—C1	178.8 (2)	O1i—Mn1—O1—C1	−172.39 (18)
Mn1—N1—C2—C1	−1.5 (2)	N1—Mn1—O1—C1	2.38 (16)
O1—C1—C2—C3	−176.7 (2)	N1i—Mn1—O1—C1	35.2 (4)
O2—C1—C2—C3	3.7 (3)

Symmetry code: (i) −x+3/2, −y+3/2, z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···O2ii	0.86	1.95	2.811 (3)	173
O1W—H1WA···O2iii	0.87	1.96	2.818 (2)	167
O1W—H1WB···O2iv	0.73	2.02	2.751 (2)	176

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