source: e-Polymers year: 2003 number: P_023 doi: not available
Abstract: N-heterocyclic carbenes are divalent carbon species, which are commonly used as neutral, two-electron ligands with a negligible pi-back-bonding tendency. They behave as phosphine mimics, yet they are better sigma-donors and they form stronger bonds to metal centres than most phosphines. Their electronic and steric properties are liable to ample modification simply by varying the substituents on the nitrogen atoms. Therefore, N-heterocyclic carbenes constitute a promising new class of ligands available for catalyst's engineering and fine tuning, and a great deal of attention has been paid to them recently. We found that the 18-electron complexes RuCl2(p-cymene)(NHC) (NHC is an N-heterocyclic carbene ligand) were versatile and efficient promoters for both ring-opening metathesis polymerisation and ATRP of methyl methacrylate and styrene. Herein, we report preliminary results in Kharasch chemistry when various RuCl2(p-cymene)-(NHC) complexes were used as catalyst precursors.