Complexes with a Metal Phosphorus Triple Bond – a Novel Class of Highly Reactive Compounds

Abstract

A novel approach to highly reactive phosphido complex intermediates of the type [LnM=P→M′(CO)5] (M′ = Cr, W) is achieved via the Cp* migration from a σ-bound situation at a P atom in a phosphinidene complex [Cp*P{W(CO)5}2] to the η5-coordination at the transition metal. Consequently those compounds show a high “side-on” reactivity. Their reaction behavior with phosphaalkynes, alkynes and nitriles leads to novel metala-phosphaheterocycles. Furthermore, the use of the corresponding As analogue [Cp*As{W(CO)5}2] yields via thermolysis reaction the tetranuclear tungsten clusters, which indicate besides the formation of the triple bond intermediate [Cp*(CO)2W[As→W(CO)5] the occurrence of a second Cp* eliminated intermediate [As{W(CO)5}2].