Facile synthesis of four-membered ring platinalactam complexes and the single-crystal structure of [Pt{CH(CN)C(O)N(CO2Et)}(cod)](cod = cycloocta-1,5-diene)

Abstract

Treatment of the complexes [PtCl₂L₂][L = PPh₃ or L₂= cycloocta-1,5-diene (cod) or 1,2-bis(diphenylphosphino)ethane (dppe)] with 1 equivalent of ethyl N-cyanoacetylcarbamate and an excess of silver(I) oxide in refluxing dichloromethane afforded the new platinalactam complexes [P[graphic omitted](CO₂Et)}L₂](L = PPh₃; L₂= cod or dppe) in high yield. A single-crystal X-ray diffraction study on the cod derivative confirms the presence of a planar four-membered platinalactam ring system. Molecular parameters and NMR spectroscopic properties of the metallacycles are discussed, in terms of the differing trans influences of the C- and N-donor atoms of the metallacycle.