Reaction behavior of sterically hindered ?-(substituted methyl)acrylic esters withtert-butoxy radicals studied by a nitroxide trapping technique

Autor:	Eriko Sato, W. Ken Busfield, Per B. Zetterlund, Bunichiro Yamada, Ian D. Jenkins
Rok vydání:	2003
Předmět:	Nitroxide mediated radical polymerization Polymers and Plastics Radical Organic Chemistry Methyl radical Free-radical reaction Photochemistry Hydrogen atom abstraction Medicinal chemistry Adduct chemistry.chemical_compound chemistry Materials Chemistry Methyl methacrylate Methyl group
Zdroj:	Polymer International. 52:1676-1682
ISSN:	1097-0126 0959-8103
DOI:	10.1002/pi.1293
Popis:	The nitroxide free radical trapping technique in connection with HPLC and electrospray ionization mass spectrometry has been employed to study reactions of tert-butoxy radicals with methyl α-(2-methyl-2-carbomethoxypropyl)acrylate (methyl methacrylate dimer (MMAD)) and methyl α-(2,2,2-tris(carbomethoxy)ethyl)acrylate (M(TM)EA). It has been shown that the adduct radical derived from MMAD undergoes β-fragmentation and expels the 2-carbomethoxy-2-propyl radical. No fragmentation was detected in the case of M(TM)EA. Rate coefficients of trapping and β-fragmentation of the tert-butoxy radical in the literature have enabled estimations of absolute rate coefficients for additions of the tert-butoxy radical and the methyl radical to monomer, hydrogen abstraction from monomer by the tert-butoxy radical, and β-fragmentation of the adduct radical (MMAD only). The reactions of tert-butoxy radicals with M(TM)EA are slower than with MMAD due to the steric hindrance of the α-substituent. Copyright © 2003 Society of Chemical Industry
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::a80b72e0fa42619e1b7fb2827f9f222b https://doi.org/10.1002/pi.1293 Zobrazit plný text záznamu Plný text