Thermally stable pseudo-third-generation Grubbs ruthenium catalysts with pyridine–phosphinimine ligand

Abstract

The ligand precursors 2-(R3PN)CH2Py (R=Ph(1a), Cy(2a)) were prepared from reaction of pyridine azide with various phosphine ligands. Reaction of 1a or 2a with RuCl2(CHPh)(Py)2(H2IMes) (Py=pyridine) afforded the ruthenium alkylidene complex RuCl2(CHPh)(PyCH2(NPR3))(H2IMes) (R=Ph(1), Cy(2)). Both catalysts showed good thermal stability and latent behavior toward RCM and ROMP reactions.