Dipotassium [N,N 0 -(propane-1,3-diyl)- dioxamato-j 4 O,N,N 0 ,O 0 ]copper(II) trihydrate: redetermination at 100 K Daniel J. Price* and Marta Martinez-Belmonte WestCHEM, Department of Chemistry, University of Glasgow, University Avenue, Glasgow G12 8QQ, Scotland Correspondence e-mail: d.price@chem.gla.ac.uk Received 3 October 2007; accepted 19 November 2007 Key indicators: single-crystal X-ray study; T = 100 K; mean (C–C) = 0.003 A ˚ ; disorder in main residue; R factor = 0.032; wR factor = 0.083; data-to-parameter ratio = 18.8. Redetermination of the structure of the title compound, K 2 [Cu(C 7 H 6 N 2 O 6 )]3H 2 O, at 100 K reveals conformational disorder in the almost planar copper-containing molecular dianions and clarifies the complex hydrogen-bonded network involving the water molecules. The asymmetric unit contains two independent formula units. In one of the [Cu(C 7 H 6 N 2 O 6 )] 2 dianions, the propyl chain is disordered over two orientiations, with site-occupancy factors of 0.852 (5) and 0.148 (5). Related literature The structure of the title compound at room temperature has been reported previously, see: Zhu et al. (1999). A related monohydrate structure has been reported, see: Fritsky et al. (1999). For other related structures, see: Rodrı´guez-Romero et al. (1996); Cervera et al. (1998); Pei et al. (1986). For synthetic details, see: Nonoyama et al. (1976). Experimental Crystal data K 2 [Cu(C 7 H 6 N 2 O 6 )]3H 2 O M r = 409.98 Triclinic, P 1 a = 10.4738 (17) A ˚ b = 10.5498 (15) A ˚ c = 12.940 (2) A ˚  = 72.322 (6)   = 78.691 (7)   = 87.622 (6)  V = 1335.6 (4) A ˚ 3 Z =4 Mo K radiation  = 2.31 mm 1 T = 100 (2) K 0.4  0.2  0.2 mm Data collection Bruker APEXII CCD diffractometer Absorption correction: multi-scan (SADABS; Sheldrick, 2003) T min = 0.408, T max = 0.631 19933 measured reflections 7887 independent reflections 6530 reflections with I >2(I) R int = 0.031 Refinement R[F 2 >2(F 2 )] = 0.032 wR(F 2 ) = 0.084 S = 1.05 7887 reflections 419 parameters 18 restraints H atoms treated by a mixture of independent and constrained refinement Á max = 1.14 e A ˚ 3 Á min = 0.49 e A ˚ 3 Table 1 Hydrogen-bond geometry (A ˚ ,  ). D—HA D—H HA DA D—HA O13—H13BO16 i 0.83 (2) 2.05 (2) 2.884 (3) 177 (2) O13—H13AO5 0.82 (2) 2.00 (2) 2.800 (2) 166 (3) O14—H14AO2 0.82 (2) 2.13 (2) 2.918 (2) 163 (2) O14—H14BO3 ii 0.82 (2) 1.99 (2) 2.806 (2) 169 (2) O15—H15AO14 iii 0.82 (2) 1.98 (2) 2.795 (2) 171 (2) O15—H15BO18 iv 0.84 (2) 2.05 (2) 2.870 (3) 167 (2) O16—H16AO12 v 0.80 (3) 2.00 (3) 2.701 (2) 147 (2) O16—H16BO2 iii 0.80 (3) 1.97 (3) 2.740 (2) 162 (2) O17—H17AO9 0.83 (2) 2.00 (3) 2.654 (2) 136 (2) O17—H17BO4 vi 0.84 (2) 2.01 (3) 2.807 (2) 163 (2) O18—H18AO16 vii 0.84 (2) 2.24 (3) 2.953 (3) 144 (2) O18—H18BO17 0.83 (2) 2.02 (2) 2.842 (3) 173 (2) Symmetry codes: (i) x þ 1; y; z; (ii) x  1; y þ 1; z þ 1; (iii) x  1; y þ 2; z þ 1; (iv) x; y þ 1; z; (v) x  1; y; z; (vi) x; y þ 1; z; (vii) x; y  1; z. Data collection: APEX2 (Bruker, 2006); cell refinement: APEX2; data reduction: APEX2; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publi- cation: WinGX (Farrugia, 1999). We are grateful to the University of Glasgow for funding to MMB. Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BI2246). References Brandenburg, K. (1999). DIAMOND. Release 2.1c. Crystal Impact GbR, Bonn, Germany. Bruker (2006). APEX2. Version 2.1-4. Bruker AXS Inc., Madison, Wisconsin, USA. Cervera, B., Sanz, J. L., Ibanez, M.J., Vila, G., Lloret, F., Julve, M., Ruiz, R., Ottenwaelder, X., Aukaullo, A., Poussereau, S., Journaux, Y. & Munoz, M. C. (1998). J. Chem. Soc. Dalton Trans. pp. 781–790. Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838. Fritsky, I. O., Dudarenko, M. M., Efetova, O. P. & Kalibabchuk, V. O. (1999). Bull. Nat. Acad. Sci. Ukraine: Geol. Chem. Biol. Sci. pp. 144–147. Nonoyama, K., Oijma, H. & Nonoyama, M. (1976). Inorg. Chim. Acta, 20, 127– 133. Pei, Y., Kahn, O. & Sletten, J. (1986). J. Am. Chem. Soc. 108, 3143–3145. Rodrı´guez-Romero, F. V., Ruiz-Pe ´rez, C. & Solans, X. (1996). Acta Cryst. C52, 1415–1417. Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Go ¨ttingen, Germany. Sheldrick, G. M. (2003). SADABS. University of Go ¨ttingen, Germany. Zhu, Z.-C., Xu, Z. & Huang, X.-Y. (1999). Chin. J. Struct. Chem. 18, 131–135. metal-organic compounds m3158 # 2007 International Union of Crystallography doi:10.1107/S1600536807060837 Acta Cryst. (2007). E63, m3158 Acta Crystallographica Section E Structure Reports Online ISSN 1600-5368