Diaqua-bis-(4-carb-oxy-2-ethyl-1H-imidazole-5-carboxyl-ato-κN,O)cadmium dihydrate.

The asymmetric unit of the title compound, [Cd(C(7)H(7)N(2)O(4))(2)(H(2)O)(2)]·2H(2)O, consists of one Cd(II) ion, one 4-carb-oxy-2-ethyl-1H-imidazole-5-carboxyl-ate anion, one coordinated water mol-ecule and one lattice water mol-ecule. The Cd(II) ion lies on a twofold axis, and is hexa-coordinated by four O atoms from water mol-ecules and carboxyl-ate groups and two N atoms from two imidazole rings, in a distorted octa-hedral arrangement. An extensive framework of N-H⋯O and O-H⋯O hydrogen bonds with the participation of coordinated and free water mol-ecules is found in the crystal structure, which contributes to the formation of a three-dimensional structure.

Related literature

For coordination polymers built up from related imidazole–carboxyl­ate ligands, see: Li et al. (2011 ▶); Wang et al. (2008 ▶); Zhang et al. (2010 ▶); Tian et al. (2010 ▶). For a related CdII complex based on the ligand 5-carb­oxy-2-methyl-1H-imidazole-4-carboxyl­ate, see: Nie et al. (2007 ▶).

Experimental

Crystal data

[Cd(C7H7N2O4)2(H2O)2]·2H2O

M = 550.76

Monoclinic,

a = 9.844 (2) Å

b = 17.084 (3) Å

c = 12.855 (3) Å

β = 102.21 (3)°

V = 2113.0 (8) Å3

Z = 4

Mo Kα radiation

μ = 1.10 mm−1

T = 293 K

0.30 × 0.25 × 0.18 mm

Data collection

Bruker SMART 1000 CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2004 ▶) T min = 0.733, T max = 0.826

8379 measured reflections

1898 independent reflections

1560 reflections with I > 2σ(I)

R int = 0.042

Refinement

R[F 2 > 2σ(F 2)] = 0.028

wR(F 2) = 0.072

S = 1.23

1898 reflections

142 parameters

6 restraints

H-atom parameters constrained

Δρmax = 0.77 e Å−3

Δρmin = −0.78 e Å−3

Data collection: SMART (Bruker, 2004 ▶); cell refinement: SAINT (Bruker, 2004 ▶); data reduction: SAINT; 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.

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536811021428/bh2359sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811021428/bh2359Isup2.hkl

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

[Cd(C7H7N2O4)2(H2O)2]·2H2O	F(000) = 1112
Mr = 550.76	Dx = 1.731 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 1702 reflections
a = 9.844 (2) Å	θ = 2.5–25.9°
b = 17.084 (3) Å	µ = 1.10 mm−1
c = 12.855 (3) Å	T = 293 K
β = 102.21 (3)°	Block, colourless
V = 2113.0 (8) Å3	0.30 × 0.25 × 0.18 mm
Z = 4

Bruker SMART 1000 CCD area-detector diffractometer	1898 independent reflections
Radiation source: fine-focus sealed tube	1560 reflections with I > 2σ(I)
graphite	Rint = 0.042
φ and ω scans	θmax = 25.2°, θmin = 3.2°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −11→10
Tmin = 0.733, Tmax = 0.826	k = −20→20
8379 measured reflections	l = −15→15

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)] = 0.028	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.072	H-atom parameters constrained
S = 1.23	w = 1/[σ2(Fo2) + (0.0164P)2 + 5.0177P] where P = (Fo2 + 2Fc2)/3
1898 reflections	(Δ/σ)max < 0.001
142 parameters	Δρmax = 0.77 e Å−3
6 restraints	Δρmin = −0.78 e Å−3
0 constraints

	x	y	z	Uiso*/Ueq
Cd1	0.0000	0.20278 (3)	0.2500	0.03340 (14)
O1	0.5880 (2)	0.14665 (16)	0.0777 (2)	0.0399 (7)
O2	0.5052 (3)	0.26839 (16)	0.0774 (2)	0.0439 (7)
O3	0.3063 (3)	0.33738 (16)	0.1245 (2)	0.0470 (7)
H3	0.3668	0.3140	0.1034	0.071*
O4	0.1229 (2)	0.30656 (16)	0.1896 (2)	0.0414 (6)
N1	0.3597 (3)	0.08847 (17)	0.1520 (2)	0.0288 (7)
H9	0.4044	0.0442	0.1391	0.035*
N2	0.1837 (3)	0.14937 (18)	0.1946 (2)	0.0287 (7)
C1	0.2678 (3)	0.2036 (2)	0.1605 (2)	0.0244 (7)
C2	0.3782 (3)	0.1654 (2)	0.1332 (3)	0.0266 (8)
C3	0.2420 (3)	0.0805 (2)	0.1895 (3)	0.0311 (8)
C4	0.1894 (4)	0.0046 (3)	0.2202 (4)	0.0506 (11)
H4A	0.2676	−0.0260	0.2578	0.061*
H4B	0.1289	0.0145	0.2693	0.061*
C5	0.1137 (8)	−0.0418 (4)	0.1323 (6)	0.127 (3)
H5A	0.0380	−0.0115	0.0927	0.190*
H5B	0.0780	−0.0880	0.1595	0.190*
H5C	0.1750	−0.0565	0.0867	0.190*
C6	0.5001 (3)	0.1949 (2)	0.0929 (3)	0.0316 (8)
C7	0.2289 (3)	0.2871 (2)	0.1586 (3)	0.0320 (8)
O1W	−0.1380 (3)	0.1871 (2)	0.0846 (2)	0.0691 (11)
H2W	−0.2184	0.1706	0.0594	0.104*
H1W	−0.1026	0.2090	0.0386	0.104*
O2W	−0.0139 (3)	0.45120 (19)	0.1075 (3)	0.0695 (10)
H4W	0.0458	0.4235	0.1478	0.104*
H3W	−0.0307	0.4344	0.0448	0.104*

	U11	U22	U33	U12	U13	U23
Cd1	0.02313 (19)	0.0344 (3)	0.0474 (2)	0.000	0.01810 (16)	0.000
O1	0.0283 (13)	0.0410 (18)	0.0557 (16)	−0.0001 (12)	0.0208 (12)	−0.0051 (13)
O2	0.0461 (15)	0.0289 (18)	0.0667 (18)	−0.0072 (12)	0.0345 (14)	0.0007 (13)
O3	0.0492 (16)	0.0276 (16)	0.075 (2)	−0.0021 (13)	0.0379 (15)	0.0003 (14)
O4	0.0338 (13)	0.0300 (16)	0.0671 (17)	0.0057 (12)	0.0261 (13)	0.0010 (14)
N1	0.0266 (14)	0.0189 (17)	0.0439 (17)	0.0022 (12)	0.0143 (13)	−0.0014 (13)
N2	0.0244 (14)	0.0242 (18)	0.0404 (16)	−0.0010 (12)	0.0134 (13)	0.0001 (13)
C1	0.0238 (15)	0.0191 (18)	0.0320 (17)	−0.0039 (15)	0.0098 (14)	−0.0003 (15)
C2	0.0210 (15)	0.030 (2)	0.0307 (18)	−0.0007 (14)	0.0088 (14)	−0.0007 (15)
C3	0.0261 (17)	0.028 (2)	0.041 (2)	0.0000 (15)	0.0115 (16)	0.0016 (16)
C4	0.041 (2)	0.032 (3)	0.084 (3)	0.0013 (18)	0.026 (2)	0.013 (2)
C5	0.173 (7)	0.092 (6)	0.123 (6)	−0.090 (6)	0.049 (5)	−0.033 (5)
C6	0.0250 (17)	0.039 (3)	0.0337 (19)	−0.0047 (17)	0.0123 (15)	−0.0069 (18)
C7	0.0298 (17)	0.030 (2)	0.0383 (19)	−0.0029 (16)	0.0123 (16)	0.0000 (17)
O1W	0.0318 (14)	0.134 (4)	0.0430 (16)	−0.0229 (18)	0.0119 (13)	0.0104 (19)
O2W	0.085 (2)	0.049 (2)	0.068 (2)	0.0309 (18)	0.0014 (18)	−0.0144 (17)

Cd1—N2i	2.270 (3)	N2—C1	1.375 (4)
Cd1—N2	2.270 (3)	C1—C2	1.375 (5)
Cd1—O1W	2.284 (3)	C1—C7	1.476 (5)
Cd1—O1Wi	2.284 (3)	C2—C6	1.491 (5)
Cd1—O4	2.368 (3)	C3—C4	1.481 (5)
Cd1—O4i	2.368 (3)	C4—C5	1.450 (7)
O1—C6	1.239 (4)	C4—H4A	0.9700
O2—C6	1.275 (5)	C4—H4B	0.9700
O3—C7	1.284 (4)	C5—H5A	0.9600
O3—H3	0.8096	C5—H5B	0.9600
O4—C7	1.239 (4)	C5—H5C	0.9600
N1—C3	1.353 (4)	O1W—H2W	0.8388
N1—C2	1.356 (5)	O1W—H1W	0.8355
N1—H9	0.9080	O2W—H4W	0.8424
N2—C3	1.317 (5)	O2W—H3W	0.8381
N2i—Cd1—N2	132.60 (15)	N1—C2—C6	122.5 (3)
N2i—Cd1—O1W	83.59 (10)	C1—C2—C6	131.7 (3)
N2—Cd1—O1W	91.00 (11)	N2—C3—N1	110.1 (3)
N2i—Cd1—O1Wi	91.00 (11)	N2—C3—C4	126.1 (3)
N2—Cd1—O1Wi	83.59 (10)	N1—C3—C4	123.9 (3)
O1W—Cd1—O1Wi	166.5 (2)	C5—C4—C3	114.9 (4)
N2i—Cd1—O4	154.13 (10)	C5—C4—H4A	108.5
N2—Cd1—O4	72.67 (10)	C3—C4—H4A	108.5
O1W—Cd1—O4	91.54 (10)	C5—C4—H4B	108.5
O1Wi—Cd1—O4	98.55 (11)	C3—C4—H4B	108.5
N2i—Cd1—O4i	72.67 (10)	H4A—C4—H4B	107.5
N2—Cd1—O4i	154.13 (10)	C4—C5—H5A	109.5
O1W—Cd1—O4i	98.55 (11)	C4—C5—H5B	109.5
O1Wi—Cd1—O4i	91.54 (10)	H5A—C5—H5B	109.5
O4—Cd1—O4i	83.03 (12)	C4—C5—H5C	109.5
C7—O3—H3	108.4	H5A—C5—H5C	109.5
C7—O4—Cd1	115.4 (2)	H5B—C5—H5C	109.5
C3—N1—C2	108.6 (3)	O1—C6—O2	125.3 (3)
C3—N1—H9	117.7	O1—C6—C2	118.1 (4)
C2—N1—H9	133.5	O2—C6—C2	116.6 (3)
C3—N2—C1	106.7 (3)	O4—C7—O3	122.1 (4)
C3—N2—Cd1	139.4 (2)	O4—C7—C1	119.1 (3)
C1—N2—Cd1	113.7 (2)	O3—C7—C1	118.8 (3)
N2—C1—C2	108.9 (3)	Cd1—O1W—H2W	136.5
N2—C1—C7	119.0 (3)	Cd1—O1W—H1W	110.6
C2—C1—C7	132.1 (3)	H2W—O1W—H1W	112.2
N1—C2—C1	105.8 (3)	H4W—O2W—H3W	111.6

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O2	0.81	1.66	2.468 (4)	172.
O2W—H4W···O4	0.84	2.16	2.904 (4)	147.
O2W—H3W···O1ii	0.84	2.08	2.874 (4)	157.
O1W—H1W···O2ii	0.84	1.97	2.788 (4)	165.
O1W—H2W···O1iii	0.84	2.01	2.768 (3)	150.
N1—H9···O2Wiv	0.91	1.86	2.771 (4)	177.

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3⋯O2	0.81	1.66	2.468 (4)	172
O2W—H4W⋯O4	0.84	2.16	2.904 (4)	147
O2W—H3W⋯O1i	0.84	2.08	2.874 (4)	157
O1W—H1W⋯O2i	0.84	1.97	2.788 (4)	165
O1W—H2W⋯O1ii	0.84	2.01	2.768 (3)	150
N1—H9⋯O2Wiii	0.91	1.86	2.771 (4)	177

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