[4+2] versus [2+2] Homodimerization in P(V)‎ Derivatives of 2,4-Disubstituted Phospholes

Abstract EN

Phosphole P(V) derivatives are interesting building blocks for various applications from ligand synthesis to material sciences.

We herein describe the preparation and characterisation of new 2,4-disubstituted oxo-, thiooxo-, and selenooxophospholes.

The nature of the substituents on the phosphole ring determines the reactivity of these compounds towards homodimerization reactions.

Aryl and trimethylsilyl substituted oxophospholes undergo selective [4+2] dimerization, whereas, for thiooxo- and selenooxophospholes, light-induced, selective [2+2] head-to-head dimerization occurs in the case of aryl substituents.

DFT calculations provide some insights on these differences in reactivity.