Reactions of bis(silyl)palladium(II) complexes with allyl halides. Synthesis of mono(silyl)palladium(II) halides and X-ray structure of trans-PdCl(SiF 2Ph)(PMe 2Ph) 2

Abstract

Reactions of trans-Pd(SiF 2Ph) 2L 2 (L=PMe 3 ( 1a), PMe 2Ph ( 1b), PMePh 2 ( 1c)) with allyl bromide readily proceeded in CH 2Cl 2 at −20°C to form CH 2CHCH 2SiF 2Ph and the corresponding bromo(silyl)palladium complexes, trans-PdBr(SiF 2Ph)L 2 ( 2a– 2c) in high selectivities. Treatment of 1a– 1c with dry HCl in CH 2Cl 2 at −20°C gave silyl chloride complexes, trans-PdCl(SiF 2Ph)L 2 ( 3a– 3c), respectively. Complexes 2a– 2c and 3a– 3c were isolated and characterized by NMR spectroscopy and/or elemental analysis. One of the complexes, trans-PdCl(SiF 2Ph)(PMe 2Ph) 2 ( 3b), was identified also by X-ray diffraction study. Relevance of bis-silyl complexes to catalytic silylation of allylic compounds with disilanes is discussed.