X-ray study of two new cadmium acetato complexes

Abstract

Two new cadmium acetate compounds, Cd(tpy)(Ac)(2)center dot 2H(2)O (1) and Cd-2(bbip)(2) (Ac)(3)center dot 0.5S(2)O(8)center dot 2H(2)O (2) (tpy = 2,2',2 ''-terpyridine; bbip = 2,6-(benzimidazol-2-yl)pyridine; Ac = acetate), have been synthesized and their crystal structures determined. Compound 1 is monoclinic, P2(1)/n, a = 8.4899(11), b = 23.169(3), c = 10.9224(14) angstrom, beta = 7.493(2)degrees, V = 2049.1(5) angstrom(3), Z = 4, R = 0.037 for 4552 N-i independent reflections and for 1619 N-o observed [I > 2 sigma(I)] reflections. Compound 1 is monomeric, with a heptacoordinate cadmium ion bonded to two bidentate acetate groups and a tridentate tpy; two hydration water molecules complete the formula unit. Compound 2 is triclinic P-1(-), a = 10.8412(7), b = 14.4051(9), c = 15.5354(10) angstrom, alpha = 82.889(1), beta = 77.953(1), gamma = 85.805(1)degrees, V = 2351.73(3) angstrom(3), Z = 2, R = 0./044, N-i = 9014, N-o = 6837. The binuclear structure has two independent Cd atoms per asymmetric unit, two bbip tridentate ligands (one attached to each cation) and three acetate groups, displaying a range of different coordination features.