5-COORDINATE HYDRIDO-COMPLEXES [PTX(H)(N,N-CHELATE)(OLEFIN)] (X=CL, BR OR I) - CRYSTAL-STRUCTURE OF H)(2,9-ME2-1,10-PHENANTHROLINE)(DIMETHYL-MALEATE)]

The title compounds were obtained by oxidative addition of hydrogen ha lides to suitable [Pt(N,N-chelate)(olefin)] species. The properties of the ligands and of the electrophile which allow the isolation of stab le products must meet very strict requirements. The crystal structure of [PtCl(H)(2,9-Me2-1,10-phenanthroline)(dimethyl maleate)] was determ ined by single-crystal X-ray diffraction. Substitution, insertion, and elimination reactions were performed on one hydride complex.