ETA(3)-TRIMETHYLENEMETHANE, ETA(3)-OXATRIMETHYLENEMETHANE, AND ETA(3)-AZATRIMETHYLENEMETHANE COMPLEXES OF PLATINUM FROM ETA(3)-PROPARGYL ALLENYL PRECURSORS/

Synthetic methodology for eta(3)-trimethylenemethane, eta(3)-oxatrimet hylenemethane, and eta(3)-azatrimethylenemethane (eta(3)-C3X) complexe s of platinum from eta(3)propargyl/allenyl precursors is presented. Th e preparative methods are based on addition of a carbon, oxygen, or ni trogen nucleophile to C(2) of the eta(3)-propargyl/allenyl ligand, Str uctural properties of these three classes of organoplatinum complexes are considered in terms of slipped platinum eta(3)-allyl and puckered platinacyclic representations. Reactions of the title complexes includ e protonation and alkylation at the negative terminus X of the zwitter ionic structure and cycloaddition of eta(3)-C3X to electrophilic olefi ns and isocyanates.