Poly[[{μ3-dihydrogen [(pyridin-4-yl­methyl­imino)­bis­(methyl­ene)]diphos­phon­ato-κ5O:O′,N,O′′:N′}copper(II)] dihydrate]

Zhang, S.-Y.; Zhou, Z.-G.; Wang, K.-J.

doi:10.1107/S1600536811052512

metal-organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 68| Part 1| January 2012| Pages m38-m39

doi:10.1107/S1600536811052512

Open

access

Poly[[{μ₃-dihydrogen [(pyridin-4-ylmethylimino)bis(methylene)]diphosphonato-κ⁵O:O′,N,O′′:N′}copper(II)] dihydrate]

Shi-Yong Zhang,^a Zhong-Gao Zhou ^a ^* and Ke-Jun Wang ^a

^aCollege of Chemistry and Chemical Engineering, Gannan Normal University, Ganzhou, Jiangxi 341000, People's Republic of China
^*Correspondence e-mail: zhgzhou@foxmail.com

(Received 13 November 2011; accepted 6 December 2011; online 10 December 2011)

In the title polymer, {[Cu(C₈H₁₂N₂O₆P₂)]·2H₂O}_n, the geometry of the five-coordinate Cu^II ion can best be described as slightly distorted square-pyramidal formed by one N and two O atoms of an N(CH₂PO₃H)₂ group and one N atom from a pyridine ring. The elongated apex of the pyramid is occupied by one O atom from a third diphosphonate ligand. The interconnection of Cu²⁺ ions by the diphosphonate ligands results in the formation of a double-chain array along the b axis, in which the two sub-chains are interlocked by pairs of PO₃ groups. The outside of each sub-chain is decorated by other PO₃ groups. These double chains are further assembled into a three-dimensional supramolecular architecture via a large number of O—H⋯O hydrogen bonds between the phosphonate groups and lattice water molecules.

Related literature

For background to metal phosphonate chemistry, see: Maeda (2004 ); Mao (2007 ); Shimizu et al. (2009 ). For the synthetic strategy of attaching functional groups to a phosphonic acid ligand, see: Drumel et al. (1995 ); Mao et al. (2002 ); Liang & Shimizu (2007 ); Du et al. (2006 , 2010b ). For a structurally related complex, see: Song & Mao (2005 ). For the zwitterionic behavior of aminophosphonic acid, see: Yang et al. (2008 ); Du et al. (2009 , 2010a ).

Experimental

Crystal data

[Cu(C₈H₁₂N₂O₆P₂)]·2H₂O
M_r = 393.71
Triclinic, $[P \overline 1]$
a = 8.9250 (3) Å
b = 9.0000 (3) Å
c = 10.5066 (3) Å
α = 75.648 (2)°
β = 67.124 (2)°
γ = 67.126 (2)°
V = 711.75 (4) Å³
Z = 2
Mo Kα radiation
μ = 1.80 mm⁻¹
T = 296 K
0.40 × 0.03 × 0.02 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ) T_min = 0.605, T_max = 0.746
7659 measured reflections
3267 independent reflections
2309 reflections with I > 2σ(I)
R_int = 0.043

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.118
S = 1.03
3267 reflections
202 parameters
6 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.50 e Å⁻³
Δρ_min = −0.60 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1B⋯O1W	0.82	1.68	2.494 (4)	169
O6—H6C⋯O2W	0.82	1.75	2.567 (5)	172
O1W—H1WA⋯O5ⁱ	0.83 (2)	1.92 (2)	2.746 (4)	177 (5)
O1W—H1WB⋯O5ⁱⁱ	0.84 (2)	1.93 (2)	2.747 (4)	167 (5)
O2W—H2WA⋯O1ⁱⁱⁱ	0.85 (2)	2.09 (3)	2.882 (4)	155 (5)
O2W—H2WB⋯O3^iv	0.85 (2)	1.96 (3)	2.776 (4)	161 (6)
Symmetry codes: (i) x+1, y, z; (ii) -x+1, -y+1, -z; (iii) x-1, y+1, z; (iv) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); 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) and DIAMOND (Brandenburg, 2010 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811052512/fj2483sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811052512/fj2483Isup2.hkl

checkCIF report

Comment top

During the past few decades, the syntheses of metal phosphonates with various structures has attracted much attention, owing to their potential applications in areas such as catalysis, ion exchange, intercalation chemistry, and material chemistry (Maeda, 2004; Mao, 2007; Shimizu et al., 2009). The strategy of attaching functional groups such as amine, hydroxyl, carboxylate, sulfonate, and sulfone groups to the phosphonic acid has proven to be an effective method for the isolation of a variety of metal phosphonates with new structures (Drumel et al., 1995; Mao et al., 2002; Liang & Shimizu, 2007; Du et al. 2006, 2010b). Recently, we are interested in the combination of multiple functional groups to phosphonic acid as a more complex ligand. Herein, we report a copper(II) phosphonate based on an amino-bis(methyl-phosphonic acid) ligand, which contains pyridyl group as an additional functional group. As far as we are aware, only one layered cobalt(II) phosphonate has been reported based on the same ligand (Song & Mao, 2005).

The title compound (I) features a one-dimensional double-chain structure. The formula of it contains one Cu²⁺ ion, one H₂L^2- anion and two lattice water molecules. Cu(1) ion is five-coordinate and its coordination geometry can be described as a slightly distorted square-pyramid (Fig. 1): the square plane is formed by one N and two O atoms of a N(CH₂PO₃H)₂ group as well as one N atom of a pyridyl group from two H₂L^2- ligand, and the prolonged apex of the pyramid is occupied by one O atom from a third H₂L^2- ligand. The H₂L^2- ligand in compound (I) acts as a pentadentate chelating and bridging ligand. It chelates one Cu²⁺ ion by its N(CH₂PO₃H)₂ group in a tridentate fashion (2O and 1 N), and also bridges with other two Cu²⁺ ions via its pyridyl group and a third O atom (Scheme 1). The two phosphonate groups of the H₂L^2- ligand both are 1H-protonated as the requirement for charge balance and also as indicated by two much longer P—O bonds. It is worthy of note that the strongly basic N atom in the H₂L^2- ligand is not protonated but bonded to a Cu²⁺ ion, which is rarely observed for phosphonic acid ligands containing a tertiary amine group (Yang et al., 2008; Du et al., 2009, 2010a).

The interconnection of the Cu²⁺ ions by the HL^2- anions results in the formation of a one-dimensional double-chain array along the b-axis, in which the two sub-chains are inter-locked by pairs of P(1)O₃ groups and the outside of each sub-chain is decorated by P(2)O₃ groups. It is worthy of note that such two sub-chains are related by inversion centers, and the shortest Cd···Cd distance between them is 5.170 (4) Å while that in each sub-chain is 9.000 (1) Å. These double-chains are further assembled into a three-dimensional supramolecular architecture via a large number of hydrogen bonds between the phosphonate groups and lattice water molecules (Fig. 3 and Table 1).

Related literature top

For background to metal phosphonate chemistry, see: Maeda (2004); Mao (2007); Shimizu et al. (2009). For the synthetic strategy of attaching functional groups to a phosphonic acid ligand, see: Drumel et al. (1995); Mao et al. (2002); Liang & Shimizu (2007); Du et al. (2006, 2010b). For a structurally related complex, see: Song & Mao (2005). For the zwitterionic behavior of aminophosphonic acid, see: Yang et al. (2008); Du et al. (2009, 2010a).

Experimental top

4-Pyridyl-CH₂N(CH₂PO₃H₂)₂ (0.2 mmol) was dissolved in 4 ml H₂O and poured into a test tube, then CuCl₂.2H₂O (0.15 mmol) dissolved in 8 ml EtOH was carefully layered onto it and left to stand at room temperature. Blue column-shaped crystals of (I) were obtained after about two weeks later. IR data for (I) (KBr, cm^-1): 3477(s), 3228(s), 3141(m), 3079(m), 2975(m), 2913(m), 2376(m), 1846(m), 1624(s), 1502(m), 1448(m), 1433(m), 1350(m), 1266(s), 1221(m), 1173(s), 1140(versus), 1065(s), 1051(s), 1032(s), 945(s), 929(m), 906(m), 866(m), 844(m), 795(m), 742(m), 648(m), 588(s), 524(m), 482(m), 453(m).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 2010); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. View of the selected unit of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. [Symmetry codes: (i) x, y + 1, z; (ii) -x + 1, -y + 1, -z + 1; (iii) x, y - 1, z.]
	Fig. 2. View of the double-chain structure of (I) along the b-axis. The CPO₃ tetrahedra are shaded in purple. Cu, N and C atoms are drawn as cyan, blue and black circles, respectively.
	Fig. 3. View of the structure of (I) down the b-axis. For display details, see the caption for Fig. 2. Hydrogen bonds are represented by dashed lines.

Poly[[{µ₃-dihydrogen [(pyridin-4-ylmethylimino)bis(methylene)]diphosphonato- κ⁵O:O',N,O'':N'}copper(II)] dihydrate] top

Crystal data top

[Cu(C₈H₁₂N₂O₆P₂)]·2H₂O	Z = 2
M_r = 393.71	F(000) = 402
Triclinic, P1	D_x = 1.837 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.9250 (3) Å	Cell parameters from 1430 reflections
b = 9.0000 (3) Å	θ = 2.1–27.6°
c = 10.5066 (3) Å	µ = 1.80 mm⁻¹
α = 75.648 (2)°	T = 296 K
β = 67.124 (2)°	Needle, blue
γ = 67.126 (2)°	0.40 × 0.03 × 0.02 mm
V = 711.75 (4) Å³

Data collection top

Bruker APEXII CCD diffractometer	3267 independent reflections
Radiation source: fine-focus sealed tube	2309 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.043
phi and ω scans	θ_max = 27.6°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −10→11
T_min = 0.605, T_max = 0.746	k = −11→11
7659 measured reflections	l = −13→13

Refinement top

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.118	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ²(F_o²) + (0.055P)² + 0.1702P] where P = (F_o² + 2F_c²)/3
3267 reflections	(Δ/σ)_max < 0.001
202 parameters	Δρ_max = 0.50 e Å⁻³
6 restraints	Δρ_min = −0.60 e Å⁻³

Crystal data top

[Cu(C₈H₁₂N₂O₆P₂)]·2H₂O	γ = 67.126 (2)°
M_r = 393.71	V = 711.75 (4) Å³
Triclinic, P1	Z = 2
a = 8.9250 (3) Å	Mo Kα radiation
b = 9.0000 (3) Å	µ = 1.80 mm⁻¹
c = 10.5066 (3) Å	T = 296 K
α = 75.648 (2)°	0.40 × 0.03 × 0.02 mm
β = 67.124 (2)°

Data collection top

Bruker APEXII CCD diffractometer	3267 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2008)	2309 reflections with I > 2σ(I)
T_min = 0.605, T_max = 0.746	R_int = 0.043
7659 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	6 restraints
wR(F²) = 0.118	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.50 e Å⁻³
3267 reflections	Δρ_min = −0.60 e Å⁻³
202 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
Cu1	0.47006 (6)	0.60143 (5)	0.25556 (5)	0.02485 (17)
P1	0.69833 (14)	0.32696 (12)	0.39341 (11)	0.0237 (2)
P2	0.17163 (14)	0.57368 (13)	0.21239 (12)	0.0265 (3)
N1	0.5076 (4)	−0.1825 (4)	0.2025 (3)	0.0240 (7)
N2	0.4396 (4)	0.3746 (4)	0.2980 (3)	0.0207 (7)
C1	0.3823 (5)	−0.0485 (5)	0.1777 (4)	0.0282 (9)
H1A	0.2869	−0.0590	0.1696	0.034*
C2	0.3912 (5)	0.1042 (5)	0.1641 (4)	0.0293 (10)
H2A	0.3025	0.1945	0.1457	0.035*
C3	0.5301 (5)	0.1261 (4)	0.1773 (4)	0.0233 (9)
C4	0.6596 (6)	−0.0148 (5)	0.1992 (4)	0.0294 (9)
H4A	0.7570	−0.0076	0.2065	0.035*
C5	0.6465 (5)	−0.1652 (5)	0.2102 (4)	0.0273 (9)
H5A	0.7364	−0.2575	0.2233	0.033*
C6	0.5389 (5)	0.2920 (4)	0.1674 (4)	0.0243 (9)
H6A	0.4964	0.3607	0.0933	0.029*
H6B	0.6587	0.2831	0.1412	0.029*
C7	0.5053 (5)	0.2840 (5)	0.4152 (4)	0.0235 (9)
H7A	0.5324	0.1684	0.4164	0.028*
H7B	0.4179	0.3168	0.5029	0.028*
C8	0.2500 (5)	0.4113 (5)	0.3387 (4)	0.0224 (8)
H8A	0.1931	0.4454	0.4312	0.027*
H8B	0.2255	0.3151	0.3391	0.027*
O1	0.8567 (4)	0.1971 (3)	0.3047 (3)	0.0309 (7)
H1B	0.9034	0.2423	0.2302	0.046*
O2	0.6750 (3)	0.4935 (3)	0.3111 (3)	0.0278 (6)
O3	0.7175 (4)	0.3101 (3)	0.5319 (3)	0.0307 (7)
O4	0.2907 (3)	0.6731 (3)	0.1706 (3)	0.0273 (6)
O5	0.1664 (4)	0.5097 (3)	0.0961 (3)	0.0356 (7)
O6	−0.0163 (4)	0.6712 (4)	0.2955 (3)	0.0393 (8)
H6C	−0.0137	0.7334	0.3394	0.059*
O1W	1.0256 (4)	0.3000 (4)	0.0716 (3)	0.0381 (8)
H1WA	1.065 (6)	0.366 (5)	0.078 (5)	0.057*
H1WB	0.964 (6)	0.344 (5)	0.021 (5)	0.057*
O2W	−0.0383 (5)	0.8732 (4)	0.4421 (4)	0.0462 (9)
H2WA	−0.037 (7)	0.965 (4)	0.397 (5)	0.069*
H2WB	0.053 (5)	0.832 (6)	0.464 (6)	0.069*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu1	0.0279 (3)	0.0187 (3)	0.0339 (3)	−0.0064 (2)	−0.0186 (2)	−0.0011 (2)
P1	0.0258 (6)	0.0185 (5)	0.0290 (6)	−0.0027 (4)	−0.0154 (5)	−0.0030 (4)
P2	0.0283 (6)	0.0233 (5)	0.0369 (6)	−0.0077 (5)	−0.0215 (5)	−0.0020 (5)
N1	0.0277 (18)	0.0195 (17)	0.0268 (19)	−0.0072 (14)	−0.0117 (15)	−0.0025 (14)
N2	0.0248 (17)	0.0177 (16)	0.0235 (17)	−0.0068 (14)	−0.0127 (15)	−0.0014 (13)
C1	0.026 (2)	0.023 (2)	0.042 (3)	−0.0039 (17)	−0.018 (2)	−0.0081 (19)
C2	0.030 (2)	0.022 (2)	0.040 (3)	−0.0025 (18)	−0.020 (2)	−0.0054 (18)
C3	0.028 (2)	0.0192 (19)	0.023 (2)	−0.0061 (17)	−0.0087 (18)	−0.0038 (16)
C4	0.031 (2)	0.028 (2)	0.034 (2)	−0.0097 (19)	−0.015 (2)	−0.0042 (19)
C5	0.028 (2)	0.0169 (19)	0.039 (3)	−0.0065 (17)	−0.017 (2)	−0.0003 (18)
C6	0.028 (2)	0.022 (2)	0.027 (2)	−0.0063 (17)	−0.0142 (18)	−0.0024 (17)
C7	0.031 (2)	0.0188 (19)	0.023 (2)	−0.0078 (17)	−0.0125 (18)	0.0005 (16)
C8	0.023 (2)	0.022 (2)	0.026 (2)	−0.0100 (17)	−0.0100 (18)	−0.0025 (17)
O1	0.0302 (16)	0.0228 (15)	0.0335 (17)	−0.0006 (13)	−0.0123 (14)	−0.0028 (13)
O2	0.0279 (16)	0.0194 (14)	0.0395 (17)	−0.0054 (12)	−0.0194 (14)	0.0008 (13)
O3	0.0312 (17)	0.0335 (16)	0.0321 (17)	−0.0054 (13)	−0.0200 (14)	−0.0043 (13)
O4	0.0315 (16)	0.0234 (14)	0.0367 (17)	−0.0100 (12)	−0.0243 (14)	0.0038 (13)
O5	0.049 (2)	0.0308 (16)	0.0431 (19)	−0.0148 (15)	−0.0302 (16)	−0.0026 (14)
O6	0.0290 (17)	0.0360 (18)	0.061 (2)	−0.0048 (14)	−0.0248 (16)	−0.0111 (16)
O1W	0.041 (2)	0.0387 (19)	0.042 (2)	−0.0163 (16)	−0.0204 (16)	0.0014 (15)
O2W	0.048 (2)	0.0337 (19)	0.061 (2)	−0.0053 (17)	−0.030 (2)	−0.0057 (17)

Geometric parameters (Å, º) top

Cu1—O2	1.949 (3)	C2—C3	1.390 (5)
Cu1—O4	1.949 (2)	C2—H2A	0.9300
Cu1—N1ⁱ	2.008 (3)	C3—C4	1.385 (5)
Cu1—N2	2.080 (3)	C3—C6	1.501 (5)
Cu1—O3ⁱⁱ	2.315 (3)	C4—C5	1.376 (5)
P1—O3	1.495 (3)	C4—H4A	0.9300
P1—O2	1.514 (3)	C5—H5A	0.9300
P1—O1	1.570 (3)	C6—H6A	0.9700
P1—C7	1.827 (4)	C6—H6B	0.9700
P2—O5	1.497 (3)	C7—H7A	0.9700
P2—O4	1.518 (3)	C7—H7B	0.9700
P2—O6	1.563 (3)	C8—H8A	0.9700
P2—C8	1.831 (4)	C8—H8B	0.9700
N1—C1	1.340 (5)	O1—H1B	0.8200
N1—C5	1.341 (5)	O3—Cu1ⁱⁱ	2.315 (3)
N1—Cu1ⁱⁱⁱ	2.008 (3)	O6—H6C	0.8200
N2—C7	1.489 (5)	O1W—H1WA	0.832 (19)
N2—C8	1.492 (5)	O1W—H1WB	0.836 (19)
N2—C6	1.507 (5)	O2W—H2WA	0.846 (19)
C1—C2	1.376 (6)	O2W—H2WB	0.848 (19)
C1—H1A	0.9300

O2—Cu1—O4	167.12 (11)	C3—C2—H2A	119.4
O2—Cu1—N1ⁱ	93.65 (12)	C4—C3—C2	115.6 (3)
O4—Cu1—N1ⁱ	92.92 (12)	C4—C3—C6	122.4 (4)
O2—Cu1—N2	86.48 (11)	C2—C3—C6	121.9 (3)
O4—Cu1—N2	86.29 (11)	C5—C4—C3	121.1 (4)
N1ⁱ—Cu1—N2	176.50 (13)	C5—C4—H4A	119.4
O2—Cu1—O3ⁱⁱ	96.97 (11)	C3—C4—H4A	119.4
O4—Cu1—O3ⁱⁱ	94.37 (11)	N1—C5—C4	121.9 (4)
N1ⁱ—Cu1—O3ⁱⁱ	87.53 (12)	N1—C5—H5A	119.0
N2—Cu1—O3ⁱⁱ	95.93 (11)	C4—C5—H5A	119.0
O3—P1—O2	116.53 (16)	C3—C6—N2	115.5 (3)
O3—P1—O1	108.57 (16)	C3—C6—H6A	108.4
O2—P1—O1	110.13 (17)	N2—C6—H6A	108.4
O3—P1—C7	110.01 (18)	C3—C6—H6B	108.4
O2—P1—C7	103.88 (16)	N2—C6—H6B	108.4
O1—P1—C7	107.31 (17)	H6A—C6—H6B	107.5
O5—P2—O4	115.75 (17)	N2—C7—P1	109.1 (3)
O5—P2—O6	108.56 (17)	N2—C7—H7A	109.9
O4—P2—O6	111.15 (16)	P1—C7—H7A	109.9
O5—P2—C8	112.42 (17)	N2—C7—H7B	109.9
O4—P2—C8	103.00 (16)	P1—C7—H7B	109.9
O6—P2—C8	105.44 (18)	H7A—C7—H7B	108.3
C1—N1—C5	118.3 (3)	N2—C8—P2	108.1 (3)
C1—N1—Cu1ⁱⁱⁱ	120.0 (3)	N2—C8—H8A	110.1
C5—N1—Cu1ⁱⁱⁱ	121.1 (3)	P2—C8—H8A	110.1
C7—N2—C8	111.7 (3)	N2—C8—H8B	110.1
C7—N2—C6	112.3 (3)	P2—C8—H8B	110.1
C8—N2—C6	112.8 (3)	H8A—C8—H8B	108.4
C7—N2—Cu1	107.6 (2)	P1—O1—H1B	109.5
C8—N2—Cu1	104.3 (2)	P1—O2—Cu1	119.08 (16)
C6—N2—Cu1	107.7 (2)	P1—O3—Cu1ⁱⁱ	133.88 (16)
N1—C1—C2	121.7 (4)	P2—O4—Cu1	117.93 (16)
N1—C1—H1A	119.1	P2—O6—H6C	109.5
C2—C1—H1A	119.1	H1WA—O1W—H1WB	109 (4)
C1—C2—C3	121.3 (4)	H2WA—O2W—H2WB	107 (4)
C1—C2—H2A	119.4

Symmetry codes: (i) x, y+1, z; (ii) −x+1, −y+1, −z+1; (iii) x, y−1, z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1B···O1W	0.82	1.68	2.494 (4)	169
O6—H6C···O2W	0.82	1.75	2.567 (5)	172
O1W—H1WA···O5^iv	0.83 (2)	1.92 (2)	2.746 (4)	177 (5)
O1W—H1WB···O5^v	0.84 (2)	1.93 (2)	2.747 (4)	167 (5)
O2W—H2WA···O1^vi	0.85 (2)	2.09 (3)	2.882 (4)	155 (5)
O2W—H2WB···O3ⁱⁱ	0.85 (2)	1.96 (3)	2.776 (4)	161 (6)

Symmetry codes: (ii) −x+1, −y+1, −z+1; (iv) x+1, y, z; (v) −x+1, −y+1, −z; (vi) x−1, y+1, z.

Experimental details

Crystal data
Chemical formula	[Cu(C₈H₁₂N₂O₆P₂)]·2H₂O
M_r	393.71
Crystal system, space group	Triclinic, P1
Temperature (K)	296
a, b, c (Å)	8.9250 (3), 9.0000 (3), 10.5066 (3)
α, β, γ (°)	75.648 (2), 67.124 (2), 67.126 (2)
V (Å³)	711.75 (4)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.80
Crystal size (mm)	0.40 × 0.03 × 0.02

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2008)
T_min, T_max	0.605, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	7659, 3267, 2309
R_int	0.043
(sin θ/λ)_max (Å⁻¹)	0.652

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.118, 1.03
No. of reflections	3267
No. of parameters	202
No. of restraints	6
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.50, −0.60

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 2010), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1B···O1W	0.82	1.68	2.494 (4)	169
O6—H6C···O2W	0.82	1.75	2.567 (5)	172
O1W—H1WA···O5ⁱ	0.832 (19)	1.916 (19)	2.746 (4)	177 (5)
O1W—H1WB···O5ⁱⁱ	0.836 (19)	1.93 (2)	2.747 (4)	167 (5)
O2W—H2WA···O1ⁱⁱⁱ	0.846 (19)	2.09 (3)	2.882 (4)	155 (5)
O2W—H2WB···O3^iv	0.848 (19)	1.96 (3)	2.776 (4)	161 (6)

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

Acknowledgements

This work was supported by the NSF of Jiangxi Provincial Education Department (grant No. GJJ10714).

References

Brandenburg, K. (2010). DIAMOND. Crystal Impact GbR, Bonn, Germany. Google Scholar
Bruker (2008). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Drumel, S., Janvier, P., Deniaud, D. & Bujoli, B. (1995). Chem. Commun. pp. 1051–1052. CrossRef Google Scholar
Du, Z.-Y., Sun, Y.-H., Liu, Q.-Y., Xie, Y.-R. & Wen, H.-R. (2009). Inorg. Chem. 48, 7015–7017. Web of Science CSD CrossRef PubMed CAS Google Scholar
Du, Z.-Y., Sun, Y.-H., Zhang, X.-Z., Luo, S.-F., Xie, Y.-R. & Wan, D.-B. (2010a). CrystEngComm, 12, 1774–1778. Web of Science CSD CrossRef Google Scholar
Du, Z.-Y., Wen, H.-R., Liu, C.-M., Sun, Y.-H., Lu, Y.-B. & Xie, Y.-R. (2010b). Cryst. Growth Des. 10, 3721–3726. Web of Science CSD CrossRef CAS Google Scholar
Du, Z.-Y., Xu, H.-B. & Mao, J.-G. (2006). Inorg. Chem. 45, 9780–9788. Web of Science CSD CrossRef PubMed CAS Google Scholar
Liang, J. & Shimizu, G. K. H. (2007). Inorg. Chem. 46, 10449–10451. Web of Science CSD CrossRef PubMed CAS Google Scholar
Maeda, K. (2004). Microporous Mesoporous Mater. 73, 47–55. Web of Science CrossRef CAS Google Scholar
Mao, J.-G. (2007). Coord. Chem. Rev. 251, 1493–1520. Web of Science CrossRef CAS Google Scholar
Mao, J.-G., Wang, Z. K. & Clearfield, A. (2002). Inorg. Chem. 41, 6106–6111. Web of Science CSD CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Shimizu, G. K., Vaidhyanathan, H. R. & Taylor, J. M. (2009). Chem. Soc. Rev. 38, 1430–1449. Web of Science CrossRef PubMed CAS Google Scholar
Song, J.-L. & Mao, J.-G. (2005). J. Solid State Chem. 178, 3530–3537. Web of Science CSD CrossRef Google Scholar
Yang, B.-P., Prosvirin, A. V., Guo, Y.-Q. & Mao, J.-G. (2008). Inorg. Chem. 47, 1453–1459. Web of Science CSD CrossRef PubMed CAS Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.