Metal complexes of naphthyl-substituted thiourea derivatives

The thiourea derivative N,N-diethyl-N'-2-naphthoylthiourea (1) and three N-(dialkylaminothiocarbonyl)-N'-(1-naphthyl)-arylamidines (2-4) have been synthesized and Cu-II-, Ni-II and Pd-II-complexes of them have been prepared. According to the X-ray structure analyses 1 with Cu-II and Ni-II under deprotonation forms neutral bis-chelates of nearly square-planar coordination with a cis arrangement of the O and S ligator atoms. Using their N and S atoms in 1,3 position as ligators, 2-4 in deprotonated form coordinate to Cu-II and Pd-II as neutral bis-chelates, in the case of Cu-II with, a distorted tetrahedral coordination. Pd-II is coordinated square planar and has, probably due to the spatial influence of the 1-naphthyl groups, a trans arrangement of the N and S ligator atoms.