Crystal structure of cis-di-chlorido-(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ4N)chromium(III) (oxalato-κ2O1,O2)(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ4N)chromium(III) bis(perchlorate) from synchrotron data

摘要

In the asymmetric unit of the title compound, [CrCl2(C10H24N4)][Cr(C2O4)(C10H24N4)](ClO4)2 (C10H24N4 = 1,4,8,11-tetra-aza-cyclo-tetra-decane, cyclam; C2O4 = oxalate, ox), there are two independent halves of the [CrCl2(cyclam)]+ and [Cr(ox)(cyclam)]+ cations, and one perchlorate anion. In the complex cations, which are completed by application of twofold rotation symmetry, the CrIII ions are coordinated by the four N atoms of a cyclam ligand, and by two chloride ions or one oxalate bidentate ligand in a cis arrangement, displaying an overall distorted octa-hedral coordination environment. The Cr—N(cyclam) bond lengths are in the range of 2.075?(5) to 2.096?(4)?? while the Cr—Cl and Cr—O(ox) bond lengths are 2.3358?(14) and 1.956?(4)??, respectively. Both cyclam moieties adopt the cis-V conformation. The slightly distorted tetra-hedral ClO4? anion remains outside the coordination sphere. The supra-molecular architecture includes N—H?O and N—H?Cl hydrogen bonding between cyclam NH donor groups, O atoms of the oxalate ligand or ClO4? anions and one Cl ligand as acceptors, leading to a three-dimensional network structure.