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 [L_nM=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].

Keywords::

• P ligands
• As ligands
• phosphinidene
• cyloadditions
• cyclizations
• multiple bonds