4,4'-Bipyridinium bis-(oxalato-κO,O)cuprate(II): an ion-pair complex.

The title compound, (C(10)H(10)N(2))[Cu(C(2)O(4))(2)] or (4,4'-H(2)bpy)[Cu(ox)(2)] (bpy is 4,4'-bipyridine and ox is oxalate), is an ion-pair complex comprising a protonated 4,4'-bipyridinium dication and a square-planar dioxalatocopper(II) dianion. In the centrosymmetric dianion, the Cu(II) centre is coordinated by four O atoms from the two dicrete oxalate ligands [Cu-O = 1.9245 (19) and 1.9252 (17) Å], while the planar dications are also centrosymmetric. Inter-species N-H⋯O hydrogen bonds link the cations and anions into one-dimensional chains and, together with weak intra-ion C-H⋯O inter-actions, give a two-dimensional sheet structure.

Related literature

For related background, see: Ren et al. (2007 ▶). For related structures, see, for example: Bukowska-Strzyzewska & Tosik (1979 ▶); Crawford et al. (2004 ▶); Diallo et al. (2008 ▶); Dou et al. (2007 ▶); Madhu & Das (2004 ▶); Näther et al. (2001 ▶); Tosik et al. (1990 ▶); Willett et al. (2006 ▶).

Experimental

Crystal data

(C10H10N2)[Cu(C2O4)2]

M = 397.79

Triclinic,

a = 3.6900 (7) Å

b = 9.950 (2) Å

c = 10.230 (2) Å

α = 113.77 (3)°

β = 98.43 (3)°

γ = 97.89 (3)°

V = 331.93 (15) Å3

Z = 1

Mo Kα radiation

μ = 1.70 mm−1

T = 293 K

0.41 × 0.27 × 0.22 mm

Data collection

Bruker APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (; Bruker, 2005 ▶) T min = 0.527, T max = 0.705

1761 measured reflections

1168 independent reflections

1126 reflections with I > 2σ(I)

R int = 0.013

Refinement

R[F 2 > 2σ(F 2)] = 0.027

wR(F 2) = 0.073

S = 1.09

1168 reflections

115 parameters

H-atom parameters constrained

Δρmax = 0.30 e Å−3

Δρmin = −0.29 e Å−3

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: SAINT-Plus (Bruker, 2005 ▶); data reduction: SAINT-Plus; 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 datablocks I, global. DOI: 10.1107/S1600536809039117/zs2010sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809039117/zs2010Isup2.hkl

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

(C10H10N2)[Cu(C2O4)2]	Z = 1
Mr = 397.79	F(000) = 201
Triclinic, P1	Dx = 1.990 Mg m−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 3.6900 (7) Å	Cell parameters from 1168 reflections
b = 9.950 (2) Å	θ = 2.2–25.1°
c = 10.230 (2) Å	µ = 1.70 mm−1
α = 113.77 (3)°	T = 293 K
β = 98.43 (3)°	Block, green-blue
γ = 97.89 (3)°	0.41 × 0.27 × 0.22 mm
V = 331.93 (15) Å3

Bruker APEXII CCD area-detector diffractometer	1168 independent reflections
Radiation source: fine-focus sealed tube	1126 reflections with I > 2σ(I)
graphite	Rint = 0.013
φ and ω scans	θmax = 25.1°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −4→4
Tmin = 0.527, Tmax = 0.705	k = −9→11
1761 measured reflections	l = −11→12

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)] = 0.027	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.073	H-atom parameters constrained
S = 1.09	w = 1/[σ2(Fo2) + (0.0434P)2 + 0.1814P] where P = (Fo2 + 2Fc2)/3
1168 reflections	(Δ/σ)max < 0.001
115 parameters	Δρmax = 0.30 e Å−3
0 restraints	Δρmin = −0.29 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
Cu1	0.0000	0.0000	0.5000	0.02273 (16)
C1	0.9693 (6)	0.2924 (3)	0.0264 (3)	0.0263 (5)
H1	1.0658	0.3392	−0.0273	0.032*
C2	0.7599 (6)	0.1481 (3)	−0.0443 (3)	0.0228 (5)
H2	0.7140	0.0971	−0.1459	0.027*
C3	0.6154 (6)	0.0779 (2)	0.0367 (2)	0.0182 (4)
C4	0.6955 (7)	0.1599 (3)	0.1887 (3)	0.0265 (5)
H4	0.6054	0.1165	0.2461	0.032*
C5	0.9057 (7)	0.3037 (3)	0.2534 (3)	0.0312 (6)
H5	0.9580	0.3582	0.3547	0.037*
C6	0.4733 (6)	0.2586 (3)	0.5616 (3)	0.0232 (5)
C7	0.3414 (6)	0.2770 (3)	0.7045 (2)	0.0224 (5)
N1	1.0353 (5)	0.3657 (2)	0.1713 (2)	0.0273 (4)
H1A	1.1664	0.4564	0.2135	0.033*
O1	0.6801 (5)	0.3636 (2)	0.5609 (2)	0.0342 (4)
O2	0.3514 (5)	0.12699 (19)	0.45407 (17)	0.0286 (4)
O3	0.1187 (5)	0.16185 (19)	0.69418 (18)	0.0265 (4)
O4	0.4569 (5)	0.39568 (19)	0.81441 (18)	0.0313 (4)

	U11	U22	U33	U12	U13	U23
Cu1	0.0285 (2)	0.0171 (2)	0.0166 (2)	−0.00496 (16)	0.00626 (16)	0.00411 (17)
C1	0.0250 (12)	0.0251 (12)	0.0318 (13)	0.0015 (10)	0.0060 (10)	0.0167 (11)
C2	0.0249 (11)	0.0219 (12)	0.0211 (11)	0.0009 (9)	0.0046 (9)	0.0102 (10)
C3	0.0155 (10)	0.0184 (11)	0.0216 (11)	0.0041 (9)	0.0043 (8)	0.0095 (9)
C4	0.0319 (13)	0.0245 (12)	0.0218 (12)	−0.0003 (10)	0.0082 (10)	0.0101 (10)
C5	0.0360 (14)	0.0262 (13)	0.0237 (13)	−0.0002 (11)	0.0047 (10)	0.0059 (11)
C6	0.0244 (11)	0.0224 (12)	0.0214 (12)	0.0018 (9)	0.0051 (9)	0.0092 (10)
C7	0.0235 (11)	0.0221 (12)	0.0208 (12)	0.0022 (9)	0.0046 (9)	0.0096 (10)
N1	0.0242 (10)	0.0160 (10)	0.0371 (12)	−0.0022 (8)	0.0040 (9)	0.0099 (9)
O1	0.0425 (10)	0.0237 (9)	0.0309 (10)	−0.0083 (8)	0.0111 (8)	0.0101 (8)
O2	0.0381 (9)	0.0205 (8)	0.0196 (8)	−0.0057 (7)	0.0102 (7)	0.0037 (7)
O3	0.0332 (9)	0.0208 (8)	0.0198 (8)	−0.0059 (7)	0.0079 (7)	0.0062 (7)
O4	0.0389 (10)	0.0203 (9)	0.0227 (9)	−0.0070 (7)	0.0063 (7)	0.0018 (7)

Cu1—O3	1.9245 (19)	C4—C5	1.367 (4)
Cu1—O3i	1.9245 (19)	C4—H4	0.9300
Cu1—O2i	1.9252 (17)	C5—N1	1.331 (3)
Cu1—O2	1.9252 (17)	C5—H5	0.9300
C1—N1	1.327 (3)	C6—O1	1.210 (3)
C1—C2	1.369 (3)	C6—O2	1.288 (3)
C1—H1	0.9300	C6—C7	1.557 (3)
C2—C3	1.397 (3)	C7—O4	1.221 (3)
C2—H2	0.9300	C7—O3	1.272 (3)
C3—C4	1.395 (3)	N1—H1A	0.8600
C3—C3ii	1.485 (4)
O3—Cu1—O3i	180.0	C5—C4—H4	119.9
O3—Cu1—O2i	93.91 (7)	C3—C4—H4	119.9
O3i—Cu1—O2i	86.09 (7)	N1—C5—C4	119.9 (2)
O3—Cu1—O2	86.09 (7)	N1—C5—H5	120.1
O3i—Cu1—O2	93.91 (7)	C4—C5—H5	120.1
O2i—Cu1—O2	180.00 (8)	O1—C6—O2	126.2 (2)
N1—C1—C2	120.4 (2)	O1—C6—C7	119.2 (2)
N1—C1—H1	119.8	O2—C6—C7	114.60 (19)
C2—C1—H1	119.8	O4—C7—O3	125.9 (2)
C1—C2—C3	119.7 (2)	O4—C7—C6	119.3 (2)
C1—C2—H2	120.1	O3—C7—C6	114.8 (2)
C3—C2—H2	120.1	C1—N1—C5	122.3 (2)
C4—C3—C2	117.5 (2)	C1—N1—H1A	118.9
C4—C3—C3ii	121.4 (2)	C5—N1—H1A	118.9
C2—C3—C3ii	121.1 (3)	C6—O2—Cu1	111.74 (14)
C5—C4—C3	120.3 (2)	C7—O3—Cu1	112.38 (14)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4iii	0.86	2.02	2.755 (3)	143
N1—H1A···O1iii	0.86	2.21	2.880 (3)	135
C1—H1···O4iv	0.93	2.49	3.381 (3)	160
C2—H2···O3iv	0.93	2.57	3.195 (3)	125
C4—H4···O2	0.93	2.42	3.272 (3)	153
C5—H5···O1	0.93	2.46	3.215 (3)	138

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O4i	0.86	2.02	2.755 (3)	143
N1—H1A⋯O1i	0.86	2.21	2.880 (3)	135
C1—H1⋯O4ii	0.93	2.49	3.381 (3)	160
C2—H2⋯O3ii	0.93	2.57	3.195 (3)	125
C4—H4⋯O2	0.93	2.42	3.272 (3)	153
C5—H5⋯O1	0.93	2.46	3.215 (3)	138

Symmetry codes: (i) ; (ii) .