Impact of Metal-Catalyzed Radical Terminations in ATRP

Please join Yale Chemistry for a Silliman Seminar in Inorganic Chemistry with Rinaldo Poli, Professor at the Laboratoire de Chimie de Coordination (Coordination Chemistry Laboratory) of the Centre National de la Recherche Scientifique (CNRS), from University of Toulouse.

Summary: Atom Transfer Radical Polymerization (ATRP), based on a dynamic halogen atom transfer equilibrium with a metal catalyst (scheme), is undoubtedly one of the most powerful and versatile methods to access complex and hierarchically controlled polymeric architectures. CuI/II complexes are the most investigated and successful ATRP catalysts. The method easily produces macromolecules with targeted molecular weight, narrow molecular weight distributions and high chain-end fidelity for a large variety of monomers using bench-stable initiators and catalysts. The efficiency of the process, however, is limited by the ability of the ATRP catalyst to also promote radical terminations, particularly for polyacrylate chains. There has been a long and unsettled debate on the nature of the termination products for polyacrylate radical chains, both in the absence and in the presence of catalysts. The present seminar will illustrate the state of the art in this field and our most recent results on the termination, both in the absence and in the presence of copper(I) catalysts, of polyacrylate chains and of small model radicals, namely: cyanoisopropyl Me2(CN)C•, model of poly(méthacrylonitrile); carbomethoxyisopropyl Me2(COOMe)C•, model of poly(methyl methacrylate); and carbomethyxyethyl Me(COOMe)CH•, model of poly(methyl acrylate). Our studies aim at elucidating the nature of the termination products and the intimate mechanism of the metal-catalyzed radical termination, with the ultimate goal of reducing or eliminating the impact of this phenomenon in ATRP.

For more information on Professor Poli's research: https://www.lcc-toulouse.fr/ligands-architectures-complexes-et-catalyse-equipe-g/ Faculty

Host: Professor Pat Holland.

This seminar is generously sponsored by the Mrs. Hepsa Ely Silliman Memorial Fund.

Location: Sterling Chemistry Laboratory (SCL) 160