STRUCTURES AND SPECTRAL PROPERTIES OF PALLADIUM(II) COMPLEXES OF 2-ACETYLPYRIDINE N(4)-DIMETHYLTHIOSEMICARBAZONE

Anions [loss of N(3) hydrogen of 2-acetylpyridine N(4)-dimethylthiosem icarbazone (HAc4DM)] coordinate in a planar conformation to a central palladium(II) through the pyridyl nitrogen, azomethine nitrogen and th iolato sulfur atoms. The fourth coordination site is occupied by eithe r a bromo, chloro or a second Ac4DM ligand bonding via its thiolato su lfur atom. A crystal structure of [Pd(Ac4DM)Br] shows it to be planar, while the structure of [Pd(Ac4DM)(2)] has the unusual coordination of the two anions bonding differently to the palladium centre. Spectral and structural similarities and differences between these and related nickel(II) and copper(II) complexes are considered. Copyright (C) 1996 Elsevier Science Ltd