Bis(7-amino-1,2,4-triazolo[1,5-a]pyrimidin-4-ium) bis­(oxalato-κ2O1,O2)cuprate(II) dihydrate

Caballero, A.B.; Castillo, Ó.; Rodríguez-Diéguez, A.; Salas, J.M.

doi:10.1107/S1600536811040724

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 11| November 2011| Pages m1531-m1532

doi:10.1107/S1600536811040724

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Bis(7-amino-1,2,4-triazolo[1,5-a]pyrimidin-4-ium) bis(oxalato-κ²O¹,O²)cuprate(II) dihydrate

Ana B. Caballero,^a Óscar Castillo,^b Antonio Rodríguez-Diéguez ^a and Juan M. Salas ^a ^*

^aDepartamento de Química Inorgánica, Facultad de Ciencias, Universidad de Granada, c/ Severo Ochoa s/n, E-18071 Granada, Spain, and ^bDepartamento de Química Inorgánica, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apdo. 644, E-48080 Bilbao, Spain
^*Correspondence e-mail: jsalas@ugr.es

(Received 21 September 2011; accepted 3 October 2011; online 12 October 2011)

The structure of the title ionic compound, (C₅H₆N₅)₂[Cu(C₂O₄)₂]·2H₂O, consists of a centrosymmetric copper(II) oxalate dianion, two monoprotonated molecules of the adenine analog 7-amino-1,2,4-triazolo[1,5-a]pyrimidine (7atp) and two water molecules of crystallization. The Cu^II ion, located on an inversion center, exhibits a sligthly distorted square-planar coordination geometry, in which two oxalate anions bind in a bidentate fashion. The triazolopyrimidine ligand is protonated at the N atom in position 4, instead of its most basic N atom in position 3. This fact may be explained by the network stability, which is provided through the formation of a two-dimensional wave-like network parallel to (50 $[\overline1]$ ) by N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds. These nets are further connected via C—H⋯O interactions.

Related literature

Experimental

Crystal data

(C₅H₆N₅)₂[Cu(C₂O₄)₂]·2H₂O
M_r = 547.91
Monoclinic, P 2₁ /c
a = 3.6599 (2) Å
b = 24.1977 (10) Å
c = 11.1963 (5) Å
β = 92.344 (4)°
V = 990.73 (8) Å³
Z = 2
Mo Kα radiation
μ = 1.19 mm⁻¹
T = 293 K
0.59 × 0.07 × 0.05 mm

Data collection

Oxford Diffraction Xcalibur CCD diffractometer
Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ) T_min = 0.675, T_max = 0.950
8945 measured reflections
2170 independent reflections
1476 reflections with I > 2σ(I)
R_int = 0.039

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.092
S = 0.91
2170 reflections
160 parameters
H-atom parameters constrained
Δρ_max = ? e Å⁻³
Δρ_min = ? e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N4A—H4A⋯O3ⁱ	0.86	1.85	2.685 (3)	165
O1W—H11W⋯N1Aⁱⁱ	0.86	2.38	3.197 (4)	157
O1W—H12W⋯O1ⁱⁱⁱ	0.86	2.15	2.985 (4)	163
N7A—H71A⋯O4^iv	0.86	2.00	2.856 (3)	170
N7A—H72A⋯O1W	0.86	2.01	2.793 (4)	151
C2A—H2A⋯O2^v	0.93	2.46	3.320 (3)	154
C5A—H5A⋯O2ⁱ	0.93	2.45	3.126 (3)	129
C6A—H6A⋯O3^iv	0.93	2.39	3.246 (3)	153
Symmetry codes: (i) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (ii) -x+2, -y, -z+1; (iii) -x+2, -y, -z+2; (iv) x+1, y, z; (v) x-1, y, z-1.

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); program(s) used to solve structure: SIR92 (Altomare et al., 1994 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811040724/su2318sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811040724/su2318Isup2.hkl

checkCIF report

Comment top

In the recent years, the rational design and synthesis of biomimetic systems based on the interaction of biologically relevant molecules with inorganic species has aroused a remarkable research interest. The study of these systems not only stems from the desire to better understand the complex interactions often present in different molecular biorecognition processes (Hannon, 2007), but also to afford a powerful tool for the improvement of pharmaceutical agents (Legraverend & Grierson, 2006). 1,2,4-triazolo[1,5-a]pyrimidines may be used as purine analogs to obtain new biomimetic systems with interesting physical and biological properties, which might differ from those of purine-based systems due to their slightly different atomic arrangement. Previous studies revealed that the coordination chemistry of 1,2,4-triazolo[1,5-a]pyrimidine derivatives displays great versatility, binding metal ions in several different ways, either in a monodentate (usually through the N atom in position 3), or in a bidentate fashion, bridging metal atoms and leading to binuclear or polynuclear species with interesting metal-metal interactions (Salas et al., 1999; Caballero et al., 2011). However, few examples containing a protonated form of the triazolopyrimidine have been reported, most of them bearing the 5,7-dimethylated derivative (Szlyk et al., 2002; Maldonado et al., 2005; Maldonado et al., 2008). To the best of our knowledge, the copper(II) complex reported herein is the only one obtained with the protonated form of the 7-amino derivative, 7-amino-1,2,4-triazolo[1,5-a]pyrimidine (7atp).

The molecular structure of the title compound is illustrated in Fig. 1. It consists of an dianionic copper(II) oxalate complex, showing a square planar geometry, two monoprotonated 7atp cations and two crystallization water molecules. The copper(II) ion is coordinated to two oxalate anions, which display a bidentate \k²O,O' mode and are related by an inversion centre. The protonation of 7atp occured through the N atom in position 4, N4, in a neutral-slightly basic media. This may be favoured by the formation of a stable two-dimensional network built from N-H···O, O-H···N and O-H···O hydrogen bonds involving the crystallization water molecules, the oxalate O atoms and the amine group (Table 1 and Fig. 2). These nets are further connected via C-H···O interactions (Table 1).

Related literature top

For the design and synthesis of biomimetic systems, see: Hannon (2007); Legraverend & Grierson (2006). For the coordination chemistry of 1,2,4-triazolo[1,5-a]pyrimidine derivatives, see: Salas et al. (1999); Caballero et al. (2011). For coordination compounds of the protonated form of triazolopyrimidine, most of them bearing the 5,7-dimethylated derivative, see: Szlyk et al. (2002); Maldonado et al. (2005, 2008). AUTHOR: please supply values for the following data names which are missing from the CIF: _refine_diff_density_max _refine_diff_density_min _diffrn_reflns_theta_full _diffrn_measured_fraction_theta_full _diffrn_reflns_theta_full _diffrn_measured_fraction_theta_max _diffrn_measured_fraction_theta_full

Experimental top

The title compound was prepare by dissolving K₂[Cu(ox)₂].2H₂O (0.16 mmol, 0.057 g) in 10 ml of a hot aqueous solution of potassium oxalate dihydrated (0.16 mmol, 0.029 g). 10 ml of an aqueous solution of 7-amino-1,2,4-triazolo[1,5-a]pyrimidine (7atp) (0.032 mmol, 0.043 g) was then added and the colour changed from blue to green. The solution was stirred at 50° C for 30 min, and then left standing at room temperature. After one day, prismatic dark-green crystals of the polymeric complex {[Cu(ox)(7atp)₂].3H₂O}_n were formed and filtered off. After 3–4 days needle-shaped blue crystals of the title complex were isolated and used for the present X-ray diffraction studies.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis CCD (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. ORTEP representation of the asymmetric unit of the title compound, showing the atom labels and displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. View along the a-axis showing the formation of the hydrogen bonded (thin blue lines) layer (a); view of the packing of the layers (b).

Bis(7-amino-1,2,4-triazolo[1,5-a]pyrimidin-4-ium) bis(oxalato-κ²O¹,O²)cuprate(II) dihydrate top

Crystal data top

(C₅H₆N₅)₂[Cu(C₂O₄)₂]·2H₂O	F(000) = 558
M_r = 547.91	D_x = 1.837 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 8945 reflections
a = 3.6599 (2) Å	θ = 3.1–27.1°
b = 24.1977 (10) Å	µ = 1.19 mm⁻¹
c = 11.1963 (5) Å	T = 293 K
β = 92.344 (4)°	Needle, blue
V = 990.73 (8) Å³	0.59 × 0.07 × 0.05 mm
Z = 2

Data collection top

Oxford Diffraction Xcalibur CCD diffractometer	2170 independent reflections
Radiation source: fine-focus sealed tube	1476 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.039
ω scans	θ_max = 27.1°, θ_min = 3.1°
Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2006)	h = −3→4
T_min = 0.675, T_max = 0.950	k = −30→30
8945 measured reflections	l = −14→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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.092	H-atom parameters constrained
S = 0.91	w = 1/[σ²(F_o²) + (0.0552P)²] where P = (F_o² + 2F_c²)/3
2170 reflections	(Δ/σ)_max < 0.001
160 parameters	Δρ_max = 0.47 e Å⁻³
0 restraints	Δρ_min = −0.42 e Å⁻³

Crystal data top

(C₅H₆N₅)₂[Cu(C₂O₄)₂]·2H₂O	V = 990.73 (8) Å³
M_r = 547.91	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 3.6599 (2) Å	µ = 1.19 mm⁻¹
b = 24.1977 (10) Å	T = 293 K
c = 11.1963 (5) Å	0.59 × 0.07 × 0.05 mm
β = 92.344 (4)°

Data collection top

Oxford Diffraction Xcalibur CCD diffractometer	2170 independent reflections
Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2006)	1476 reflections with I > 2σ(I)
T_min = 0.675, T_max = 0.950	R_int = 0.039
8945 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	0 restraints
wR(F²) = 0.092	H-atom parameters constrained
S = 0.91	Δρ_max = 0.47 e Å⁻³
2170 reflections	Δρ_min = −0.42 e Å⁻³
160 parameters

Special details top

Experimental. (CrysAlis RED; Oxford Diffraction, 2006) Analytical numeric absorption correction using a multifaceted crystal.

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles

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	0.50000	0.00000	1.00000	0.0235 (2)
O1	0.8421 (5)	0.03719 (7)	1.10908 (16)	0.0295 (6)
O2	1.0514 (6)	0.12235 (8)	1.14517 (17)	0.0308 (7)
O3	0.6886 (6)	0.15536 (7)	0.93468 (16)	0.0305 (7)
O4	0.4741 (5)	0.06976 (7)	0.91704 (15)	0.0238 (6)
C1	0.8723 (7)	0.08907 (11)	1.0863 (2)	0.0203 (8)
C2	0.6629 (8)	0.10777 (10)	0.9703 (2)	0.0209 (8)
N1A	0.7487 (7)	0.11549 (9)	0.4729 (2)	0.0255 (7)
N3A	0.6315 (6)	0.20038 (10)	0.39005 (19)	0.0259 (7)
N4A	0.9285 (6)	0.25338 (9)	0.5496 (2)	0.0230 (7)
N7A	1.1147 (7)	0.10032 (9)	0.6956 (2)	0.0297 (8)
N8A	0.8882 (6)	0.15695 (8)	0.54508 (18)	0.0193 (7)
C2A	0.6026 (8)	0.14399 (12)	0.3835 (2)	0.0264 (9)
C3A	0.8143 (8)	0.20707 (10)	0.4929 (2)	0.0203 (8)
C5A	1.1084 (8)	0.24886 (11)	0.6569 (2)	0.0250 (9)
C6A	1.1821 (8)	0.19969 (11)	0.7099 (2)	0.0238 (8)
C7A	1.0687 (7)	0.15005 (11)	0.6543 (2)	0.0215 (8)
O1W	0.9004 (13)	−0.00801 (11)	0.6425 (3)	0.1037 (16)
H2A	0.48460	0.12670	0.31850	0.0320*
H4A	0.88760	0.28530	0.51800	0.0280*
H5A	1.18500	0.28100	0.69600	0.0300*
H6A	1.30870	0.19870	0.78360	0.0290*
H71A	1.22680	0.09520	0.76370	0.0360*
H72A	1.03300	0.07250	0.65480	0.0360*
H11W	1.00140	−0.03050	0.59390	0.1560*
H12W	0.95310	−0.02300	0.71050	0.1560*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu1	0.0302 (3)	0.0162 (2)	0.0232 (3)	−0.0033 (2)	−0.0109 (2)	0.0037 (2)
O1	0.0395 (13)	0.0194 (9)	0.0280 (11)	−0.0060 (9)	−0.0163 (9)	0.0058 (8)
O2	0.0368 (13)	0.0263 (10)	0.0282 (11)	−0.0057 (9)	−0.0135 (9)	−0.0037 (9)
O3	0.0431 (13)	0.0175 (10)	0.0297 (11)	−0.0070 (9)	−0.0121 (9)	0.0062 (8)
O4	0.0318 (12)	0.0176 (9)	0.0210 (10)	−0.0046 (8)	−0.0126 (8)	0.0031 (7)
C1	0.0203 (15)	0.0206 (13)	0.0199 (13)	−0.0003 (12)	−0.0013 (11)	0.0007 (11)
C2	0.0231 (15)	0.0197 (13)	0.0198 (14)	−0.0013 (12)	0.0001 (11)	−0.0015 (11)
N1A	0.0287 (14)	0.0247 (12)	0.0226 (12)	−0.0018 (11)	−0.0032 (10)	−0.0034 (9)
N3A	0.0259 (13)	0.0319 (13)	0.0197 (12)	0.0030 (11)	−0.0022 (10)	0.0052 (10)
N4A	0.0253 (13)	0.0185 (11)	0.0248 (12)	0.0040 (10)	−0.0019 (10)	0.0034 (9)
N7A	0.0424 (16)	0.0253 (13)	0.0203 (12)	0.0031 (12)	−0.0109 (11)	0.0036 (10)
N8A	0.0216 (13)	0.0206 (11)	0.0156 (11)	0.0012 (10)	−0.0020 (9)	0.0007 (9)
C2A	0.0243 (16)	0.0347 (16)	0.0199 (15)	−0.0011 (14)	−0.0026 (12)	−0.0033 (12)
C3A	0.0184 (14)	0.0221 (13)	0.0205 (14)	0.0037 (12)	0.0017 (11)	0.0038 (11)
C5A	0.0215 (15)	0.0282 (15)	0.0253 (15)	0.0000 (12)	−0.0003 (12)	−0.0058 (12)
C6A	0.0211 (15)	0.0311 (15)	0.0188 (14)	0.0003 (13)	−0.0049 (11)	0.0006 (12)
C7A	0.0190 (15)	0.0282 (14)	0.0174 (13)	0.0018 (12)	0.0021 (11)	0.0036 (11)
O1W	0.196 (4)	0.0385 (16)	0.075 (2)	0.000 (2)	−0.014 (2)	−0.0046 (14)

Geometric parameters (Å, º) top

Cu1—O1	1.9349 (18)	N3A—C2A	1.370 (4)
Cu1—O4	1.9272 (17)	N4A—C5A	1.351 (3)
Cu1—O1ⁱ	2.8879 (18)	N4A—C3A	1.346 (3)
Cu1—O1ⁱⁱ	1.9349 (18)	N7A—C7A	1.298 (3)
Cu1—O4ⁱⁱ	1.9272 (17)	N8A—C3A	1.368 (3)
Cu1—O1ⁱⁱⁱ	2.8879 (18)	N8A—C7A	1.376 (3)
O1—C1	1.287 (3)	N4A—H4A	0.8600
O2—C1	1.215 (3)	N7A—H72A	0.8600
O3—C2	1.224 (3)	N7A—H71A	0.8600
O4—C2	1.283 (3)	C1—C2	1.548 (3)
O1W—H11W	0.8600	C5A—C6A	1.352 (4)
O1W—H12W	0.8600	C6A—C7A	1.408 (4)
N1A—C2A	1.311 (3)	C2A—H2A	0.9300
N1A—N8A	1.374 (3)	C5A—H5A	0.9300
N3A—C3A	1.318 (3)	C6A—H6A	0.9300

O1—Cu1—O4	85.10 (7)	C3A—N4A—H4A	121.00
O1—Cu1—O1ⁱ	96.74 (6)	C5A—N4A—H4A	121.00
O1—Cu1—O1ⁱⁱ	180.00	H71A—N7A—H72A	120.00
O1—Cu1—O4ⁱⁱ	94.90 (7)	C7A—N7A—H72A	120.00
O1—Cu1—O1ⁱⁱⁱ	83.26 (6)	C7A—N7A—H71A	120.00
O1ⁱ—Cu1—O4	84.58 (6)	O1—C1—O2	126.0 (2)
O1ⁱⁱ—Cu1—O4	94.90 (7)	O2—C1—C2	119.9 (2)
O4—Cu1—O4ⁱⁱ	180.00	O1—C1—C2	114.1 (2)
O1ⁱⁱⁱ—Cu1—O4	95.43 (6)	O3—C2—C1	120.4 (2)
O1ⁱ—Cu1—O1ⁱⁱ	83.26 (6)	O4—C2—C1	114.8 (2)
O1ⁱ—Cu1—O4ⁱⁱ	95.43 (6)	O3—C2—O4	124.8 (2)
O1ⁱ—Cu1—O1ⁱⁱⁱ	180.00	N1A—C2A—N3A	117.0 (2)
O1ⁱⁱ—Cu1—O4ⁱⁱ	85.10 (7)	N3A—C3A—N4A	130.6 (2)
O1ⁱⁱ—Cu1—O1ⁱⁱⁱ	96.74 (6)	N4A—C3A—N8A	119.0 (2)
O1ⁱⁱⁱ—Cu1—O4ⁱⁱ	84.58 (6)	N3A—C3A—N8A	110.4 (2)
Cu1—O1—C1	112.79 (15)	N4A—C5A—C6A	122.9 (2)
Cu1—O1—Cu1^iv	96.74 (7)	C5A—C6A—C7A	120.5 (2)
Cu1^iv—O1—C1	98.07 (15)	N8A—C7A—C6A	114.3 (2)
Cu1—O4—C2	112.90 (15)	N7A—C7A—C6A	127.0 (2)
H11W—O1W—H12W	102.00	N7A—C7A—N8A	118.7 (2)
N8A—N1A—C2A	101.3 (2)	N3A—C2A—H2A	121.00
C2A—N3A—C3A	101.8 (2)	N1A—C2A—H2A	121.00
C3A—N4A—C5A	118.9 (2)	N4A—C5A—H5A	119.00
C3A—N8A—C7A	124.5 (2)	C6A—C5A—H5A	119.00
N1A—N8A—C3A	109.5 (2)	C5A—C6A—H6A	120.00
N1A—N8A—C7A	126.0 (2)	C7A—C6A—H6A	120.00

O4—Cu1—O1—C1	5.64 (17)	C2A—N3A—C3A—N8A	−0.3 (3)
O4—Cu1—O1—Cu1^iv	−96.07 (7)	C5A—N4A—C3A—N3A	178.9 (3)
O1ⁱ—Cu1—O1—C1	−78.29 (17)	C3A—N4A—C5A—C6A	0.5 (4)
O4ⁱⁱ—Cu1—O1—C1	−174.36 (17)	C5A—N4A—C3A—N8A	−0.8 (4)
O1ⁱⁱⁱ—Cu1—O1—C1	101.71 (17)	C7A—N8A—C3A—N4A	1.2 (4)
O1—Cu1—O4—C2	−3.55 (18)	C3A—N8A—C7A—C6A	−1.1 (4)
O1ⁱ—Cu1—O4—C2	93.71 (18)	C7A—N8A—C3A—N3A	−178.6 (2)
O1ⁱⁱ—Cu1—O4—C2	176.45 (18)	N1A—N8A—C3A—N3A	0.3 (3)
O1ⁱⁱⁱ—Cu1—O4—C2	−86.29 (18)	N1A—N8A—C3A—N4A	180.0 (2)
Cu1—O1—C1—O2	175.4 (2)	N1A—N8A—C7A—C6A	−179.7 (2)
Cu1—O1—C1—C2	−6.3 (3)	N1A—N8A—C7A—N7A	−0.3 (4)
Cu1^iv—O1—C1—O2	−83.8 (3)	C3A—N8A—C7A—N7A	178.4 (3)
Cu1^iv—O1—C1—C2	94.6 (2)	O2—C1—C2—O4	−178.0 (2)
Cu1—O4—C2—O3	180.0 (2)	O2—C1—C2—O3	3.1 (4)
Cu1—O4—C2—C1	1.1 (3)	O1—C1—C2—O3	−175.4 (2)
N8A—N1A—C2A—N3A	−0.2 (3)	O1—C1—C2—O4	3.6 (3)
C2A—N1A—N8A—C3A	0.0 (3)	N4A—C5A—C6A—C7A	−0.5 (4)
C2A—N1A—N8A—C7A	178.8 (2)	C5A—C6A—C7A—N7A	−178.7 (3)
C3A—N3A—C2A—N1A	0.4 (3)	C5A—C6A—C7A—N8A	0.8 (4)
C2A—N3A—C3A—N4A	180.0 (3)

Symmetry codes: (i) x−1, y, z; (ii) −x+1, −y, −z+2; (iii) −x+2, −y, −z+2; (iv) x+1, y, z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N4A—H4A···O3^v	0.86	1.85	2.685 (3)	165
O1W—H11W···N1A^vi	0.86	2.38	3.197 (4)	157
O1W—H12W···O1ⁱⁱⁱ	0.86	2.15	2.985 (4)	163
N7A—H71A···O4^iv	0.86	2.00	2.856 (3)	170
N7A—H72A···O1W	0.86	2.01	2.793 (4)	151
N7A—H72A···N1A	0.86	2.48	2.806 (3)	103
C2A—H2A···O2^vii	0.93	2.46	3.320 (3)	154
C5A—H5A···O2^v	0.93	2.45	3.126 (3)	129
C6A—H6A···O3^iv	0.93	2.39	3.246 (3)	153

Symmetry codes: (iii) −x+2, −y, −z+2; (iv) x+1, y, z; (v) x, −y+1/2, z−1/2; (vi) −x+2, −y, −z+1; (vii) x−1, y, z−1.

Experimental details

Crystal data
Chemical formula	(C₅H₆N₅)₂[Cu(C₂O₄)₂]·2H₂O
M_r	547.91
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	3.6599 (2), 24.1977 (10), 11.1963 (5)
β (°)	92.344 (4)
V (Å³)	990.73 (8)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.19
Crystal size (mm)	0.59 × 0.07 × 0.05

Data collection
Diffractometer	Oxford Diffraction Xcalibur CCD diffractometer
Absorption correction	Analytical (CrysAlis RED; Oxford Diffraction, 2006)
T_min, T_max	0.675, 0.950
No. of measured, independent and observed [I > 2σ(I)] reflections	8945, 2170, 1476
R_int	0.039
(sin θ/λ)_max (Å⁻¹)	0.641

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.092, 0.91
No. of reflections	2170
No. of parameters	160
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.47, −0.42

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N4A—H4A···O3ⁱ	0.86	1.85	2.685 (3)	165
O1W—H11W···N1Aⁱⁱ	0.86	2.38	3.197 (4)	157
O1W—H12W···O1ⁱⁱⁱ	0.86	2.15	2.985 (4)	163
N7A—H71A···O4^iv	0.86	2.00	2.856 (3)	170
N7A—H72A···O1W	0.86	2.01	2.793 (4)	151
C2A—H2A···O2^v	0.93	2.46	3.320 (3)	154
C5A—H5A···O2ⁱ	0.93	2.45	3.126 (3)	129
C6A—H6A···O3^iv	0.93	2.39	3.246 (3)	153

Symmetry codes: (i) x, −y+1/2, z−1/2; (ii) −x+2, −y, −z+1; (iii) −x+2, −y, −z+2; (iv) x+1, y, z; (v) x−1, y, z−1.

Acknowledgements

Financial support from the Junta de Andalucía (FQM-3705 and FQM-4228) and the Spanish Ministry of Education (FPU fellowship to ABC) is gratefully acknowledged.

References

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