Ruthenium(II)-NHC pincer complexes: tuning ancillary ligand effects towards selective catalysts

Abstract

Pincer complexes have evolved into preferred catalysts for a variety of difficult transformations in organic synthesis.[1,2] Pincer-based metal complexes are stable and have great reactivities towards homogenous catalytic systems, because of the rigid tri-dentate coordination with improved chemical and thermal stability. It can play a crucial role in the catalytic cycle by providing a suitable coordination site for the substrate, weakening selective bonds, or accepting/donating electrons and protons, for providing chemical stability.[3] Furthermore, the ligand can be tuned by modifying the central metal atom as well as the pincer ligand platform, depending on the steric/electronic environment and catalytic application.