Generation and cross-coupling of benzyl and phthalimide-N-oxyl radicals in a cerium(IV) ammonium nitrate/N-hydroxyphthalimide/ArCH2R system
摘要:
A method was developed for the cross-dehydrogenative coupling of alkylarenes and related compounds with N-hydroxyphthalimide (NHPI) using cerium(IV) ammonium nitrate (CAN) to prepare O-substituted NHPI derivatives. The characteristic feature of the reaction is that NHPI plays a dual role. Thus, in the presence of CAN, NHPI generates the phthalimide-N-oxyl (PINO) radical, which abstracts a hydrogen atom from the benzyl position to form a C-centered radical. The target oxidative cross-coupling product is formed mainly through the recombination of PINO with the C-centered radical. Therefore, NHPI serves as a mediator for the radical process and a reagent for the radical cross-coupling. The target products were obtained in yields from 35 to 80%. (c) 2012 Elsevier Ltd. All rights reserved.
Generation and cross-coupling of benzyl and phthalimide-N-oxyl radicals in a cerium(IV) ammonium nitrate/N-hydroxyphthalimide/ArCH2R system
作者:Alexander O. Terent'ev、Igor B. Krylov、Mikhail Y. Sharipov、Zoya M. Kazanskaya、Gennady I. Nikishin
DOI:10.1016/j.tet.2012.10.018
日期:2012.12
A method was developed for the cross-dehydrogenative coupling of alkylarenes and related compounds with N-hydroxyphthalimide (NHPI) using cerium(IV) ammonium nitrate (CAN) to prepare O-substituted NHPI derivatives. The characteristic feature of the reaction is that NHPI plays a dual role. Thus, in the presence of CAN, NHPI generates the phthalimide-N-oxyl (PINO) radical, which abstracts a hydrogen atom from the benzyl position to form a C-centered radical. The target oxidative cross-coupling product is formed mainly through the recombination of PINO with the C-centered radical. Therefore, NHPI serves as a mediator for the radical process and a reagent for the radical cross-coupling. The target products were obtained in yields from 35 to 80%. (c) 2012 Elsevier Ltd. All rights reserved.