85696-66-8Relevant academic research and scientific papers
EFFETS POLAIRES DANS LES REACTIONS DE TRANSFERT HOMOLYTIQUE INTRAMOLECULAIRE D'HYDROGENE
Lefort, D.,Nedelec, J. Y.
, p. 2681 - 2686 (1982)
In this paper we analyse the influence of a phenyl substituent on the relative rates of the 1-5 and 1-6 intramolecular hydrogen transfers.Compared to the abstraction of an aliphatic H atom, the activation energy for the abstraction of a benzylic H atom is smaller.The effect is nevertheless more important with a primary alkyl radical (1,3 kcal/mole) than with an alkoxy radical (0,9 kcal/mole).This can be analysed in terms of a polar effect.In addition, the size of the effect is too small to make a short distance transfer of a H atom feasible; this is in keeping with the statement that H atom migration requires a linear transition state.
δ-C-H Mono- And Dihalogenation of Alcohols
Herron, Alastair N.,Liu, Dongxin,Xia, Guoqin,Yu, Jin-Quan
, p. 2766 - 2770 (2020/02/13)
Alkoxy radicals have long been known to enable remote C-H functionalization via 1,5-hydrogen atom abstraction. However, methods for their generation traditionally have relied upon highly oxidizing metals, ultraviolet radiation, or preformed peroxide intermediates, which has prevented the development of many desirable transformations. Herein we report a new bench-stable precursor that decomposes to free alkoxy radicals via a previously unreported single-electron oxidation pathway. This new precursor enables the fluorination and chlorination of remote C-H bonds under exceptionally mild conditions with exceedingly high monoselectivity. Iterative use of this precursor enables the introduction of a second halogen atom, granting access to remote dihalide motifs, including CF2 and CFCl.
