Chemically Induced Dynamic Nuclear Polarization during the Thermolysis of Alkoxyamines: A New Approach to Detect the Occurrence of H-Transfer Reactions

Maria Edeleva (1) , Sylvain R.A. Marque (2) , Denis Bertin (2) , Didier Gigmes (2) , Yohann Guillaneuf (3) , Elena Bagryanskaya (1)

1 NSU - Novosibirsk State University
2 ICR - Institut de Chimie Radicalaire
3 LCP - Laboratoire Chimie Provence

Thermal decomposition of alkoxyamines in the presence of scavengers was found to proceed with the formation of chemically induced nuclear polarization detected by 1H NMR. The distinctive Chemically Induced Dynamic Nuclear Polarization (CIDNP) features were studied using the example of three alkoxyamines: 4-nitrophenyl 2-(2,2,6,6-tetramethylpiperidin-1-yloxy)-2-methylpropanoate (1a), 4-nitrophenyl 2-(2,2-diphenyl-3-phenylimino-2,3-dihydroindol-1-yloxy)-2-methylpropanoa te (2a) and 4-nitrophenyl 2-(2,2,5,5-tetramethyl-4-phenyl-2H-imidazol-1-oxy)-2-methylpropanoate (3a) in the presence of PhSH. The analysis of CIDNP signs of methacrylate protons allows us to conclude on the occurrence of hydrogen atom transfer reaction in geminate radical pair formed in alkoxyamine thermolysis. Thus, CIDNP is a fast and sensitive method to detect the occurrence of intra/intermolecular hydrogen transfer in alkoxyamine thermolysis.

Mots clés: nitroxide mediated polymerization; alkoxyamines; H-transfer reactions; CIDNP

Domaines: Chimie

Maria Edeleva, Sylvain R.A. Marque, Denis Bertin, Didier Gigmes, Yohann Guillaneuf, et al.. Chemically Induced Dynamic Nuclear Polarization during the Thermolysis of Alkoxyamines: A New Approach to Detect the Occurrence of H-Transfer Reactions. Polymers, 2010, 2 (4), pp.364--377. ⟨10.3390/polym2040364⟩. ⟨hal-01460201⟩