Poly[di-μ(9)-citrato-cobalt(II)tetra-sodium].

The title compound, [CoNa(4)(C(6)H(5)O(7))(2)](n), was obtained under hydro-thermal conditions as a minor product. The Co(2+) cation is located on a crystallographic inversion center and is coordinated by six O atoms from two different citrate units, forming a [Co(C(6)H(5)O(7))(2)](4-) building unit with Co-O bond lengths between 2.0578 (17) and 2.0813 (16) Å. The structure features two crystallographically independent Na(+) ions. The first Na(+) cation is five-coordinated by O atoms of five carboxylate groups from four different citrate anions. The second Na(+) cation is surrounded by six O atoms of five carboxylate groups from five different citrate anions. The carboxylate groups of the citrate are completely depronona-ted, the hydroxyl group, however, is not. It is coordinated to the Co(2+) cation, and through an O-H⋯O hydrogen bond connected to a neighboring [Co(C(6)H(5)O(7))(2)](4-) building unit. The coordination modes of the carboxyl-ate O atoms vary, with one O atom being coordinated to three different Na(+) cations, three are bridging O atoms bound to two Na(+) cations and two are connected to a Co(2+) cation and a Na(+) cation, respectively. Through these inter-connections, the basic [Co(C(6)H(5)O(7))(2)](4-) building units are linked with each other through coordination of their carboxyl-ate groups to the Na(+) cations, forming a three-dimensional framework.

Related literature

For potential applications of coordination polymers in drug delivery, shape-selective sorption/separation and catalysis, see: Chen & Tong (2007 ▶); Zeng et al. (2009 ▶). Their structures vary from one-dimensional to three-dimensional architectures, see: Du & Bu et al. (2009 ▶); Qiu & Zhu (2009 ▶). For a compound containing the [Co(C6H5O7)2]4− subunit, see: Matzapetakis et al. (2000 ▶); for coordination polymers involving Na+ cations, see: Pan et al. (2011 ▶).

Experimental

Crystal data

[CoNa4(C6H5O7)2]

M = 529.09

Monoclinic,

a = 7.9792 (16) Å

b = 12.516 (3) Å

c = 8.7110 (17) Å

β = 113.84 (3)°

V = 795.7 (3) Å3

Z = 2

Mo Kα radiation

μ = 1.28 mm−1

T = 293 K

0.25 × 0.15 × 0.15 mm

Data collection

Rigaku R-AXIS RAPID-S diffractometer

Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2002 ▶) T min = 0.795, T max = 0.826

8179 measured reflections

1820 independent reflections

1493 reflections with I > 2σ(I)

R int = 0.055

Refinement

R[F 2 > 2σ(F 2)] = 0.041

wR(F 2) = 0.072

S = 1.12

1820 reflections

142 parameters

H-atom parameters constrained

Δρmax = 0.29 e Å−3

Δρmin = −0.31 e Å−3

Data collection: RAPID-AUTO (Rigaku, 1998 ▶); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2002 ▶); 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/S1600536812017606/zl2468sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812017606/zl2468Isup2.hkl

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

[CoNa4(C6H5O7)2]	F(000) = 530
Mr = 529.09	Dx = 2.208 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 7365 reflections
a = 7.9792 (16) Å	θ = 3.0–27.5°
b = 12.516 (3) Å	µ = 1.28 mm−1
c = 8.7110 (17) Å	T = 293 K
β = 113.84 (3)°	Block, yellow
V = 795.7 (3) Å3	0.25 × 0.15 × 0.15 mm
Z = 2

Rigaku R-AXIS RAPID-S diffractometer	1820 independent reflections
Radiation source: fine-focus sealed tube	1493 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.055
ω scans	θmax = 27.5°, θmin = 3.0°
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2002)	h = −10→10
Tmin = 0.795, Tmax = 0.826	k = −15→16
8179 measured reflections	l = −11→11

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)] = 0.041	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.072	H-atom parameters constrained
S = 1.12	w = 1/[σ2(Fo2) + (0.0253P)2 + 0.3552P] where P = (Fo2 + 2Fc2)/3
1820 reflections	(Δ/σ)max < 0.001
142 parameters	Δρmax = 0.29 e Å−3
0 restraints	Δρmin = −0.31 e Å−3

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.

	x	y	z	Uiso*/Ueq
Co1	1.0000	0.0000	1.0000	0.01112 (13)
Na1	0.60461 (14)	0.11777 (8)	1.03513 (13)	0.0233 (3)
Na2	0.44536 (14)	0.37904 (8)	0.83883 (13)	0.0219 (3)
O1	1.0085 (2)	0.01241 (12)	0.7650 (2)	0.0125 (4)
H1	0.9089	0.0001	0.6807	0.015*
O2	0.8226 (2)	0.12772 (13)	0.9279 (2)	0.0177 (4)
O3	0.6796 (2)	0.27068 (15)	0.7861 (2)	0.0232 (5)
O4	1.3026 (2)	0.01125 (14)	0.5009 (2)	0.0195 (4)
O5	1.4004 (2)	0.01690 (13)	0.7789 (2)	0.0186 (4)
O6	1.2231 (2)	0.10114 (14)	1.0518 (2)	0.0172 (4)
O7	1.3273 (2)	0.22348 (13)	0.9263 (2)	0.0187 (4)
C1	1.0686 (3)	0.12024 (19)	0.7524 (3)	0.0120 (5)
C2	0.9109 (3)	0.19974 (19)	0.7122 (3)	0.0138 (5)
H2A	0.9616	0.2709	0.7193	0.017*
H2B	0.8274	0.1886	0.5961	0.017*
C3	0.7974 (3)	0.1990 (2)	0.8171 (3)	0.0143 (5)
C4	1.1394 (3)	0.12288 (19)	0.6139 (3)	0.0144 (5)
H4A	1.0377	0.1087	0.5075	0.017*
H4B	1.1833	0.1944	0.6082	0.017*
C5	1.2912 (3)	0.0446 (2)	0.6347 (3)	0.0142 (5)
C6	1.2209 (3)	0.1507 (2)	0.9229 (3)	0.0132 (5)

	U11	U22	U33	U12	U13	U23
Co1	0.0127 (2)	0.0116 (2)	0.0100 (2)	0.0002 (2)	0.00553 (18)	0.0019 (2)
Na1	0.0213 (6)	0.0273 (6)	0.0241 (6)	−0.0021 (5)	0.0121 (5)	−0.0007 (5)
Na2	0.0197 (5)	0.0251 (6)	0.0217 (6)	−0.0023 (5)	0.0092 (5)	0.0015 (5)
O1	0.0139 (8)	0.0118 (9)	0.0109 (8)	−0.0036 (7)	0.0041 (7)	−0.0007 (7)
O2	0.0205 (10)	0.0181 (10)	0.0184 (10)	0.0034 (8)	0.0121 (8)	0.0051 (8)
O3	0.0212 (11)	0.0269 (11)	0.0246 (11)	0.0126 (8)	0.0126 (9)	0.0074 (9)
O4	0.0186 (10)	0.0256 (10)	0.0163 (9)	0.0018 (8)	0.0092 (8)	−0.0050 (8)
O5	0.0190 (9)	0.0187 (10)	0.0152 (9)	0.0030 (8)	0.0039 (8)	0.0003 (8)
O6	0.0176 (9)	0.0199 (10)	0.0113 (9)	−0.0018 (8)	0.0028 (7)	0.0032 (8)
O7	0.0179 (10)	0.0176 (9)	0.0219 (10)	−0.0051 (8)	0.0096 (8)	−0.0022 (8)
C1	0.0144 (12)	0.0112 (12)	0.0118 (12)	0.0005 (10)	0.0069 (10)	0.0026 (10)
C2	0.0167 (13)	0.0145 (12)	0.0111 (12)	0.0030 (10)	0.0066 (10)	0.0015 (11)
C3	0.0137 (13)	0.0150 (13)	0.0128 (13)	0.0000 (10)	0.0038 (10)	−0.0023 (11)
C4	0.0167 (13)	0.0151 (13)	0.0125 (13)	0.0032 (10)	0.0072 (11)	0.0015 (11)
C5	0.0139 (13)	0.0135 (12)	0.0160 (14)	−0.0039 (10)	0.0068 (11)	−0.0002 (11)
C6	0.0112 (12)	0.0141 (12)	0.0164 (13)	0.0042 (10)	0.0077 (11)	−0.0021 (11)

Co1—O2i	2.0578 (17)	O4—C5	1.275 (3)
Co1—O2	2.0578 (17)	O4—Na2viii	2.542 (2)
Co1—O6	2.0800 (17)	O4—Na2ix	2.545 (2)
Co1—O6i	2.0800 (17)	O5—C5	1.254 (3)
Co1—O1	2.0813 (16)	O5—Na1i	2.349 (2)
Co1—O1i	2.0813 (16)	O5—Na1x	2.508 (2)
Na1—O2	2.286 (2)	O5—Na2viii	2.562 (2)
Na1—O5i	2.349 (2)	O6—C6	1.276 (3)
Na1—O7ii	2.418 (2)	O6—Na2xi	2.424 (2)
Na1—O3iii	2.455 (2)	O7—C6	1.238 (3)
Na1—O5ii	2.508 (2)	O7—Na2x	2.416 (2)
Na2—O7ii	2.416 (2)	O7—Na1x	2.418 (2)
Na2—O6iv	2.424 (2)	C1—C4	1.526 (3)
Na2—O3	2.498 (2)	C1—C2	1.530 (3)
Na2—O4v	2.542 (2)	C1—C6	1.539 (3)
Na2—O4vi	2.545 (2)	C2—C3	1.525 (3)
Na2—O5v	2.562 (2)	C2—H2A	0.9700
O1—C1	1.451 (3)	C2—H2B	0.9700
O1—H1	0.8501	C4—C5	1.510 (3)
O2—C3	1.270 (3)	C4—H4A	0.9700
O3—C3	1.247 (3)	C4—H4B	0.9700
O3—Na1vii	2.455 (2)
O2i—Co1—O2	180.000 (1)	C3—O3—Na1vii	119.56 (16)
O2i—Co1—O6	89.06 (7)	C3—O3—Na2	154.82 (17)
O2—Co1—O6	90.94 (7)	Na1vii—O3—Na2	85.63 (7)
O2i—Co1—O6i	90.94 (7)	C5—O4—Na2viii	92.53 (15)
O2—Co1—O6i	89.06 (7)	C5—O4—Na2ix	122.91 (16)
O6—Co1—O6i	180.0	Na2viii—O4—Na2ix	102.91 (7)
O2i—Co1—O1	93.79 (7)	C5—O5—Na1i	133.69 (16)
O2—Co1—O1	86.21 (7)	C5—O5—Na1x	133.68 (16)
O6—Co1—O1	78.61 (7)	Na1i—O5—Na1x	86.18 (7)
O6i—Co1—O1	101.39 (7)	C5—O5—Na2viii	92.13 (15)
O2i—Co1—O1i	86.21 (7)	Na1i—O5—Na2viii	86.42 (6)
O2—Co1—O1i	93.79 (7)	Na1x—O5—Na2viii	116.79 (8)
O6—Co1—O1i	101.39 (7)	C6—O6—Co1	113.50 (16)
O6i—Co1—O1i	78.61 (7)	C6—O6—Na2xi	127.01 (16)
O1—Co1—O1i	180.000 (1)	Co1—O6—Na2xi	119.41 (8)
O2—Na1—O5i	123.27 (8)	C6—O7—Na2x	159.49 (17)
O2—Na1—O7ii	122.46 (7)	C6—O7—Na1x	96.72 (15)
O5i—Na1—O7ii	113.26 (7)	Na2x—O7—Na1x	98.80 (7)
O2—Na1—O3iii	112.38 (8)	O1—C1—C4	108.62 (19)
O5i—Na1—O3iii	81.95 (7)	O1—C1—C2	110.85 (19)
O7ii—Na1—O3iii	83.86 (7)	C4—C1—C2	109.76 (19)
O2—Na1—O5ii	89.53 (7)	O1—C1—C6	108.27 (19)
O5i—Na1—O5ii	93.82 (7)	C4—C1—C6	110.9 (2)
O7ii—Na1—O5ii	76.36 (7)	C2—C1—C6	108.40 (19)
O3iii—Na1—O5ii	156.27 (7)	C3—C2—C1	119.5 (2)
O7ii—Na2—O6iv	101.07 (7)	C3—C2—H2A	107.5
O7ii—Na2—O3	92.10 (7)	C1—C2—H2A	107.5
O6iv—Na2—O3	98.95 (7)	C3—C2—H2B	107.5
O7ii—Na2—O4v	132.38 (7)	C1—C2—H2B	107.5
O6iv—Na2—O4v	125.90 (7)	H2A—C2—H2B	107.0
O3—Na2—O4v	88.26 (7)	O3—C3—O2	123.0 (2)
O7ii—Na2—O4vi	86.60 (7)	O3—C3—C2	116.4 (2)
O6iv—Na2—O4vi	102.26 (7)	O2—C3—C2	120.6 (2)
O3—Na2—O4vi	158.61 (8)	C5—C4—C1	115.2 (2)
O4v—Na2—O4vi	77.09 (7)	C5—C4—H4A	108.5
O7ii—Na2—O5v	168.65 (7)	C1—C4—H4A	108.5
O6iv—Na2—O5v	77.74 (7)	C5—C4—H4B	108.5
O3—Na2—O5v	77.04 (7)	C1—C4—H4B	108.5
O4v—Na2—O5v	51.67 (6)	H4A—C4—H4B	107.5
O4vi—Na2—O5v	104.71 (7)	O5—C5—O4	123.2 (2)
C1—O1—Co1	106.67 (13)	O5—C5—C4	119.9 (2)
C1—O1—H1	109.0	O4—C5—C4	116.9 (2)
Co1—O1—H1	116.4	O7—C6—O6	124.8 (2)
C3—O2—Co1	131.01 (16)	O7—C6—C1	118.2 (2)
C3—O2—Na1	115.84 (16)	O6—C6—C1	117.0 (2)
Co1—O2—Na1	112.10 (8)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O4xii	0.85	1.79	2.640 (3)	174

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯O4i	0.85	1.79	2.640 (3)	174

Symmetry code: (i) .