Funktionelle Trimethylphosphinderivate, XI Trisphosphinomethane (R2P)3CH und isomere Phosphorylide R2P-PR2 =CH-PR2 /Functional Derivatives of Trimethylphosphine, XI Trisphosphinomethanes (R2p)3CH and Isomeric Phosphorus Ylids R2P-PR2=CH-PR2

Abstract

The metallated diphosphinomethanes Li[R₂PCHPR2′] (R,R′ = CH₃, C₆H₅) react with R2 ″PCl (R ″ = CH₃, C₆H₅) to give trisphosphinomethanes, [(R₂P)(R₂′P)(R₂″P)]CH. The reaction is shown to proceed via electrophilic attack at the phosphorus of Li[R₂PCHPR₂′]by formation of the phosphorus ylids R₂ ″P-PR₂=CH-PR₂′under certain conditions, mainly controlled by steric effects.These ylids slowly rearrange to the trisphosphino- methanes in solution,but with R ″=^tC₄H₉,the ylids are stable. The compounds are characterized by ¹H ³¹P and ¹³C NMR spectra.