New complexes of thriethanolamine (Tea): Novel structural features of [Y(TEA) 2](ClO 4) 3·3C 5H 5N and [Cd(TEA) 2](NO 3) 2

Abstract

The synthesis and characterization of the triethanolamine (TEA) complexes Sc(TEA) 2Cl 3 ( 1), Y(TEA) 2(ClO 4) 3·3C 5H 5N ( 2), Fe(TEA) 2Cl 3 ( 3), Ni(TEA) 2Cl 2 ( 4), Zn(TEA) 2Br 2 ( 5), Zn(TEA) 2(NO 3) 2 ( 6), Cd(TEA) 2Cl 2 ( 7), Cd(TEA) 2(NO 3) 2 ( 8), Pb(TEA) 2(OAc) 2 ( 9) and Bi(TEA) 2Cl 3 ( 10) are reported. The structures of 2 and 8, determined by X-ray diffraction, unexpectedly revealed eight-coordinate metals in both cases. Both structures adopt a distorted hexagonal bipyramidal configuration in which the atoms in the hexagonal plane alternately fall above and below the plane. In 2, the tree pyridines as well as the three perchlorates are involved only in hydrogen bonding to the OH groups of different TEA ligands, causing a novel distortion of the coordination sphere. Compound 8 represents an unusual example of the relatively rare coordination number eight for cadmium(II).