



Supporting information
![]() | Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536809039117/zs2010sup1.cif |
![]() | Structure factor file (CIF format) https://doi.org/10.1107/S1600536809039117/zs2010Isup2.hkl |
CCDC reference: 754050
Key indicators
- Single-crystal X-ray study
- T = 293 K
- Mean
(C-C) = 0.004 Å
- R factor = 0.027
- wR factor = 0.073
- Data-to-parameter ratio = 10.2
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor .... 2.50 PLAT042_ALERT_1_C Calc. and Reported MoietyFormula Strings Differ ?
Alert level G PLAT154_ALERT_1_G The su's on the Cell Angles are Equal (x 10000) 3000 Deg. PLAT180_ALERT_4_G Check Cell Rounding: # of Values Ending with 0 = 3 PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature 293 K PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature 293 K
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 2 ALERT level C = Check and explain 4 ALERT level G = General alerts; check 4 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 1 ALERT type 2 Indicator that the structure model may be wrong or deficient 0 ALERT type 3 Indicator that the structure quality may be low 1 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
Sodium 2-hydroxyphosphonocarboxylate (1 mmol) was dissolved in 10 ml of 50% ethanol-water after which 1 mmol of copper(II) chloride dihydrate and 1 mmol of 4,4'-bipyridine were added in sequence. After stirring for 10 min, the resulting mixture was transferred into a Teflon-lined stainless steel vessel (15 ml) which was sealed and heated at 110 °C for four days, then allowed to cool to room temperature. The blue-green single crystal blocks of the title compound (I), together with yellow-red prismatic crystals of a second unidentified component were obtained. The yield of (I) was ca. 25% (based on copper). IR (cm-1, KBr): 3439, 3110, 3060, 2921, 1665, 1581, 1487, 1409, 1273, 1205 1106, 1000, 892, 827, 798.
All H atoms were geometrically placed and refined using a riding model approximation, with C—H = 0.93 Å or N—H = 0.86 Å and Uiso(H) = 1.2Ueq (C, N).
Currently, in situ chemical reactions are of considerable interest, providing a powerful route for the preparation of novel crystals with unexpected structures, e.g. Ren et al. (2007) has reported the hydrothermal synthesis of a new coordination polymer [Cu(ox)(4,4'-bpy)]n (bpy = 4,4'-bipyridine; ox = oxalate2-) resulting from the decomposition of furan-2-carboxylic acid to give the ox2- ligand in the reaction of this acid with Cu(NO3)2.3H2O and 4,4'-bpy. In the work reported here, a novel ion-pair complex, (4,4'-H2bpy)[Cu(ox)2] (I) was obtained by using sodium 2-hydroxyphosphonocarboxylate as the ox2- source and CuCl2 . 2H2O as the copper source. Copper(II) is a relatively strong oxidant with the ability to oxidise the sodium 2-hydroxyphosphonocarboxylic giving ox2- which is generated in situ, resulting in formation of the title compound, the structure of which is reported here.
The structure of the (I) shows an ion-pair complex comprising a protonated 4,4'-bipyridine dication, (4,4'-H2bpy)2+ (Bukowska-Strzyzewska et al., 1979; Crawford et al., 2004; Dou et al., 2007; Madhu et al., 2004; Näther et al., 2001; Tosik et al., 1990; Willett et al., 2006), and a [Cu(C2O4)2]2- anion (Fig. 1). The discrete bis-(oxalato)copper(II) dianions have square planar CuO4 stereochemistry, comprising four O donor atoms from two oxalate ligands [Cu–O, 1.9245 (19), 1.9252 (17) Å] and lie across inversion centres in the unit cell. In the axial sites, the Cu–Ooxalate contacts are 2.920 (2) Å. With the 4,4'-bipyridine dications, the pyridine rings are coplanar and also have crystallographic inversion symmetry. Interamolecular N—H···O hydrogen bonds (Table 1) link the cations and anions into one-dimensional chains and together with weak intramolecular C–H···O interactions give two-dimensional sheet structures which layer down the a direction in the unit cell (Fig. 2).
For related background, see: Ren et al. (2007). For related structures, see, for example: Bukowska-Strzyzewska et al. (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).
Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT-Plus (Bruker, 2005); data reduction: SAINT-Plus (Bruker, 2005); 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 (Sheldrick, 2008).
(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 monochromator | 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 |
(C10H10N2)[Cu(C2O4)2] | γ = 97.89 (3)° |
Mr = 397.79 | V = 331.93 (15) Å3 |
Triclinic, P1 | Z = 1 |
a = 3.6900 (7) Å | Mo Kα radiation |
b = 9.950 (2) Å | µ = 1.70 mm−1 |
c = 10.230 (2) Å | T = 293 K |
α = 113.77 (3)° | 0.41 × 0.27 × 0.22 mm |
β = 98.43 (3)° |
Bruker APEXII CCD area-detector diffractometer | 1168 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | 1126 reflections with I > 2σ(I) |
Tmin = 0.527, Tmax = 0.705 | Rint = 0.013 |
1761 measured reflections |
R[F2 > 2σ(F2)] = 0.027 | 0 restraints |
wR(F2) = 0.073 | H-atom parameters constrained |
S = 1.09 | Δρmax = 0.30 e Å−3 |
1168 reflections | Δρmin = −0.29 e Å−3 |
115 parameters |
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) |
Symmetry codes: (i) −x, −y, −z+1; (ii) −x+1, −y, −z. |
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 |
Symmetry codes: (iii) −x+2, −y+1, −z+1; (iv) x+1, y, z−1. |
Experimental details
Crystal data | |
Chemical formula | (C10H10N2)[Cu(C2O4)2] |
Mr | 397.79 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 293 |
a, b, c (Å) | 3.6900 (7), 9.950 (2), 10.230 (2) |
α, β, γ (°) | 113.77 (3), 98.43 (3), 97.89 (3) |
V (Å3) | 331.93 (15) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 1.70 |
Crystal size (mm) | 0.41 × 0.27 × 0.22 |
Data collection | |
Diffractometer | Bruker APEXII CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 2005) |
Tmin, Tmax | 0.527, 0.705 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 1761, 1168, 1126 |
Rint | 0.013 |
(sin θ/λ)max (Å−1) | 0.597 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.027, 0.073, 1.09 |
No. of reflections | 1168 |
No. of parameters | 115 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.30, −0.29 |
Computer programs: APEX2 (Bruker, 2005), SAINT-Plus (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O4i | 0.86 | 2.02 | 2.755 (3) | 143.1 |
N1—H1A···O1i | 0.86 | 2.21 | 2.880 (3) | 135.3 |
C1—H1···O4ii | 0.93 | 2.49 | 3.381 (3) | 159.8 |
C2—H2···O3ii | 0.93 | 2.57 | 3.195 (3) | 124.6 |
C4—H4···O2 | 0.93 | 2.42 | 3.272 (3) | 152.6 |
C5—H5···O1 | 0.93 | 2.46 | 3.215 (3) | 138.1 |
Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) x+1, y, z−1. |
Currently, in situ chemical reactions are of considerable interest, providing a powerful route for the preparation of novel crystals with unexpected structures, e.g. Ren et al. (2007) has reported the hydrothermal synthesis of a new coordination polymer [Cu(ox)(4,4'-bpy)]n (bpy = 4,4'-bipyridine; ox = oxalate2-) resulting from the decomposition of furan-2-carboxylic acid to give the ox2- ligand in the reaction of this acid with Cu(NO3)2.3H2O and 4,4'-bpy. In the work reported here, a novel ion-pair complex, (4,4'-H2bpy)[Cu(ox)2] (I) was obtained by using sodium 2-hydroxyphosphonocarboxylate as the ox2- source and CuCl2 . 2H2O as the copper source. Copper(II) is a relatively strong oxidant with the ability to oxidise the sodium 2-hydroxyphosphonocarboxylic giving ox2- which is generated in situ, resulting in formation of the title compound, the structure of which is reported here.
The structure of the (I) shows an ion-pair complex comprising a protonated 4,4'-bipyridine dication, (4,4'-H2bpy)2+ (Bukowska-Strzyzewska et al., 1979; Crawford et al., 2004; Dou et al., 2007; Madhu et al., 2004; Näther et al., 2001; Tosik et al., 1990; Willett et al., 2006), and a [Cu(C2O4)2]2- anion (Fig. 1). The discrete bis-(oxalato)copper(II) dianions have square planar CuO4 stereochemistry, comprising four O donor atoms from two oxalate ligands [Cu–O, 1.9245 (19), 1.9252 (17) Å] and lie across inversion centres in the unit cell. In the axial sites, the Cu–Ooxalate contacts are 2.920 (2) Å. With the 4,4'-bipyridine dications, the pyridine rings are coplanar and also have crystallographic inversion symmetry. Interamolecular N—H···O hydrogen bonds (Table 1) link the cations and anions into one-dimensional chains and together with weak intramolecular C–H···O interactions give two-dimensional sheet structures which layer down the a direction in the unit cell (Fig. 2).