Preparation and Catalytic Activity of Stable 1,3-Diphosphapropene-Palladium Complexes

摘要

1,3-Diphosphapropenes[-P=C(R)-P<] bearing both sp~2 and sp~3 phosphorus atoms can be utilized as nonsymmetrical P,P-ligands. Furthermore, the sp~3 phosphorus of the P=C-P skeleton can be selectively chalcogenized to afford 3-chalcogeno-1,3-diphosphapropene ligands. This paper demonstrates several suitable 1,3-diphosphapropene derivarives for the chemistry of palladium(II) complexes. In the course of our studies on 1,3-diphosphapropenes, we utilized a sterically bulky Mes~* (2,4,6-t-Bu3C6H2) group to kinetically stabilize the inherently unstable P=C group.