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

Polymers

Maria Edeleva¹  Sylvain R. A. Marque²  Denis Bertin²  Didier Gigmes²  Yohann Guillaneuf² 

[1] Physical Chemistry Department, Novosibirsk State University, Novosibirsk, Russia; E-Mail:;UMR 6264-LCP, CNRS-Aix-Marseille Université, case 521, Avenue Escadrille Normandie-Niemen, 13397 Marseille Cedex 20, France; E-Mails:

关键词: nitroxide mediated polymerization;    alkoxyamines;    H-transfer reactions;    CIDNP;   

DOI  :  10.3390/polym2040364

来源: mdpi

【 摘 要 】

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-methylpropanoate (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.

【 授权许可】

CC BY   
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