Reactivity of terminal phosphinidene versus Li–Cl phosphinidenoid complexes in cycloaddition chemistry

Abstract

Reaction of the thermally generated transient phosphinidene complex 2 and the Li–Cl phosphinidenoid complex 7 with N-methyl-thiophene-3-carbaldimine (3) was investigated. In the first case a mixture of azaphosphiridine complex 4 and bicyclic azaphospholene complex 5 was obtained; the reaction of complex 7 yielded selectively 5. DFT modelling of the reaction of 7 with 3 supports a nucleophilic formal [4+1] cycloaddition.