A tertiary phosphine oxide ligand-based recyclable system for the Suzuki–Miyaura and Negishi reactions: evidence for pseudo-homogeneous catalysis

Abstract

A recoverable catalyst system has been developed and its application in both Suzuki–Miyaura and Negishi coupling reactions has been demonstrated. We have also investigated the nature of the active catalyst in solution – a controversial topic as recent reports describe ‘metal-free’ coupling chemistry and whether heterogeneous reactions are actually homogeneous. We classify our catalytic system as ‘pseudo-homogeneous’ and employ Pd(OAc)₂ and a commercially available cyclohexyldiphenyl phosphine oxide ligand. The system can be reused in up to 10 cycles while retaining good to excellent isolated yields.