Di-μ-chlorido-bis­[dichlorido(3,3′,5,5′-tetra­methyl-4,4′-bipyrazol-1-ium-κN2′)copper(II)] dihydrate

Kurawa, M.A.; Adams, C.J.; Orpen, A.G.

doi:10.1107/S1600536808022605

Volume 64
Part 8
Pages m1053-m1054
August 2008

Received 26 June 2008
Accepted 18 July 2008
Online 23 July 2008

Key indicators
Single-crystal X-ray study
T = 173 K
Mean (C-C) = 0.003 Å
R = 0.024
wR = 0.064
Data-to-parameter ratio = 19.8
Details

Di--chlorido-bis[dichlorido(3,3',5,5'-tetramethyl-4,4'-bipyrazol-1-ium-N^2')copper(II)] dihydrate

Mukhtar A. Kurawa,^a Christopher J. Adams ^a and A. Guy Orpen ^a ^*

^aSchool of Chemistry, University of Bristol, Bristol BS8 1TS, England
Correspondence e-mail: guy.orpen@bris.ac.uk

The structure of the centrosymmetric title compound, [Cu₂Cl₆(C₁₀H₁₅N₄)₂]·2H₂O, consists of a dimeric [{(HMe₄bpz)CuCl₃}₂] unit (HMe₄bpz is 3,3',5,5'-tetramethyl-4,4'-bipyrazol-1-ium) with two solvent water molecules. Each [HMe₄bpz]⁺ cation is bonded to a CuCl₃ unit through a Cu-N dative bond, effectively making square-planar geometry at the Cu atom. Two of these units then undergo a face-to-face dimerization so that the Cu atoms have a Jahn-Teller distorted square-pyramidal geometry with three chlorides and an N atom in the basal plane and one chloride weakly bound in the apical position. Several N-HCl, O-HCl and N-HO hydrogen bonds form a three-dimensional network.

Related literature

We have been unable to find any references in the literature to any other compound containing a monoprotonated 3,3',5,5'- tetramethylbipyrazole ligand coordinated only to one metal atom through a single nitrogen donor, but Komarchuk et al. (2004) reported a compound containing two unprotonated tetramethylbipyrazole ligands acting as ligands to a single copper atom. For an exploration of N-HCl interactions in the design and synthesis of crystal structures with desired properties such as unit-cell metrics or defined reactivity, see: Adams et al. (2005).

Experimental

Crystal data

[Cu₂Cl₆(C₁₀H₁₅N₄)₂]·2H₂O
M_r = 758.35
Triclinic, $[P \overline 1]$
a = 8.2837 (4) Å
b = 10.5907 (6) Å
c = 10.9058 (6) Å
= 102.4385 (9)°
= 108.4401 (9)°
= 110.2613 (8)°
V = 792.70 (7) Å³
Z = 1
Mo K radiation
= 1.88 mm^-1
T = 173 (2) K
0.2 × 0.13 × 0.07 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2008a) T_min = 0.787, T_max = 0.87
8466 measured reflections
3609 independent reflections
3242 reflections with I > 2(I)
R_int = 0.023

Refinement

R[F² > 2(F²)] = 0.024
wR(F²) = 0.064
S = 1.04
3609 reflections
182 parameters
2 restraints
H atoms treated by a mixture of independent and constrained refinement
_max = 0.39 e Å^-3
_min = -0.34 e Å^-3

Table 1
Selected bond lengths (Å)

Cu1-N2	1.9834 (13)
Cu1-Cl1	2.2684 (5)
Cu1-Cl3	2.2988 (4)
Cu1-Cl2	2.3345 (4)

Table 2
Hydrogen-bond geometry (Å, °)

D-HA	D-H	HA	DA	D-HA
N1-H1ACl1ⁱ	0.88	2.43	3.2625 (14)	157
N3-H3AO1ⁱⁱ	0.88	1.80	2.6786 (19)	173
N4-H4ACl3ⁱⁱⁱ	0.88	2.26	3.1435 (14)	179
O1-H11Cl1^iv	0.811 (15)	2.519 (17)	3.2640 (14)	153 (2)
O1-H11Cl3^iv	0.811 (15)	2.74 (2)	3.3031 (14)	128.5 (19)
O1-H12Cl2^v	0.800 (15)	2.404 (16)	3.1923 (14)	169 (2)
Symmetry codes: (i) -x+2, -y+3, -z+1; (ii) x, y, z-1; (iii) x, y-1, z; (iv) -x+2, -y+2, -z+1; (v) x-1, y-1, z.

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b); molecular graphics: SHELXTL (Sheldrick, 2008b); software used to prepare material for publication: SHELXTL.

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: RN2046 ).

Acknowledgements

MAK thanks Bayero University, Kano, Nigeria for funding.

References

Adams, C. J., Crawford, P. C., Orpen, A. G., Podesta, T. J. & Salt, B. (2005). Chem. Commun. pp. 2457-2458.
Bruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.
Komarchuk, V. V., Ponomarova, V. V., Krautscheid, H. & Domasevitch, K. V. (2004). Z. Anorg. Allg. Chem. 630, 1413-1418.
Sheldrick, G. M. (2008a). SADABS. University of Göttingen, Germany.
Sheldrick, G. M. (2008b). Acta Cryst. A64, 112-122.

metal-organic compounds

Di--chlorido-bis[dichlorido(3,3',5,5'-tetramethyl-4,4'-bipyrazol-1-ium-N2')copper(II)] dihydrate