The crystal and molecular structure of bis( ortho-aminobenzoato)copper-( II), Cu(H 2NC 6H 4COO) 2

Abstract

Bis ( ortho-aminobenzoato)copper ( II), Cu(H 2NC 6H 4COO) 2, crystallizes in the monoclinic space group P2 1 c with cell dimensions a = 12.95 (1), b = 5.25 (1), c = 9.39 (1) Å, and β = 93.3 (1)°. The structure was determined using three-dimensional X-ray diffraction data gathered on multiple-film, equi-inclination, integrated Weissenberg photographs taken about two crystal axes. Refinement, with anisotropic temperature factors, led to R = 3.1%. Coordination about the copper is that of a distorted octahedron. Four equatorial positions are occupied by two amino nitrogens and two carboxylate oxygens with both the nitrogens and oxygens in trans positions. The octahedral coordination is completed in the axial positions by two carbonyl oxygens which do not originate from the same ligands that occupy the equatorial sites. Each copper in the (100) plane is attached to four other coppers via carboxylate bridges to give a two-dimensional polymeric network coincident with the (100) plane. Significant hydrogen bonding occurs to strengthen the two-dimensional network, which, it is suggested, accounts for the extreme insolubility and high thermal stability of the compound.