DIRECT SYNTHESIS AND CRYSTAL STRUCTURE OF BIS(BROMIDO-BIS(1,10 PHENANTHROLINE)-COPPER(II)) NITROPRUSSIDE DIMETHYLFORMAMIDE SOLVATE

The title compound, [Cu(C12H8N2)2Br]2[Fe(CN)5(NO)]·C3H7NO, was prepared by the self-assembly of nitroprusside anion and Cu cation containing a bidentate amine in the reaction of copper powder and sodium nitroprusside with NH4Br and 1,10-phenanthroline (phen) in dimethylformamide (DMF). The complex is formed of discrete [Cu(phen)2Br]+ cations, nitroprusside [Fe(CN)5(NO)]2– anions and DMF molecules of crystallization. The cation has no crystallographically imposed symmetry; the metal atom coordinates two nitrogen atoms of two phen molecules and bromide ion. The copper coordination geometry is intermediate between a square pyramid and a trigonal bipyramid. The [Fe(CN)5(NO)]2– anion is located on an inversion centre with the nitrosyl group modelled as disordered with one of the CN groups. The DMF solvent molecule was found to be disordered about the crystallographic inversion centre; geometries were restrained to ideal values. In the solid state, alternating layers of cations and of anions plus DMF molecules are stacked along the b axis.