Photochemical Generation of Bis(Phosphine)Palladium and Bis(Phosphine)Platinum Equivalents

摘要

Ultraviolet irradiation of oxalato bis(tertiary phosphine) complexes of platinum(II) and palladium(II), Pt(C2O4)L2 and Pd(C204)L2, results in the reductive elimination of the oxalate ligand as C02 and the production of the reactive intermediates PtL2 and PdL2. These 14-electron fragments bind ligands such as olefins, perfluoroethylene, acetylenes, and trialkylphosphines to yield zerovalent metal complexes. Substrates such as alkyl, allyl or palladium, and aryl halides, organosilanes alcohols, allyl acetate, and hydrogen undergo oxidative addition reactions to yield platinum(II) derivatives. Noteworthy is the synthesis of the sterically unhindered dihydride trans-PtH2(PEt3)2 by this procedure and the clean generation of the reactive olefin complexes Pt(C2H4) PEt3)2, Pd(C2H4) (P(n-Bu)3)2, and Pd(C2H4)(diphos) in solution.