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.