Organocatalytic decarboxylative alkylation of <i>N</i>-hydroxy-phthalimide esters enabled by pyridine-boryl radicals
作者:Liuzhou Gao、Guoqiang Wang、Jia Cao、Dandan Yuan、Cheng Xu、Xuewen Guo、Shuhua Li
DOI:10.1039/c8cc06152a
日期:——
The decarboxylative alkylation of N-hydroxyphthalimide (NHPI) based reactive esters with olefins has been achieved via an organocatalytic strategy. Control experiments and density functional theory calculations suggest that these reactions involve a boryl-radical mediated decarboxylation pathway, which is different from the single electron transfer involved in decarboxylative alkylation reactions reported
Redox-Neutral Photocatalytic Cyclopropanation via Radical/Polar Crossover
作者:James P. Phelan、Simon B. Lang、Jordan S. Compton、Christopher B. Kelly、Ryan Dykstra、Osvaldo Gutierrez、Gary A. Molander
DOI:10.1021/jacs.8b05243
日期:2018.6.27
A benchtop stable, bifunctional reagent for the redox-neutral cyclopropanation of olefins has been developed. Triethylammonium bis(catecholato)iodomethylsilicate can be readily prepared on multigram scale. Using this reagent in combination with an organic photocatalyst and visible light, cyclopropanation of an array of olefins, including trifluoromethyl- and pinacolatoboryl-substituted alkenes, can
Nickel-catalyzed allylic defluorinative alkylation of trifluoromethyl alkenes with reductive decarboxylation of redox-active esters
作者:Xi Lu、Xiao-Xu Wang、Tian-Jun Gong、Jing-Jing Pi、Shi-Jiang He、Yao Fu
DOI:10.1039/c8sc04335c
日期:——
Herein, we report a nickel-catalyzed allylic defluorinative alkylation of trifluoromethyl alkenes throughreductive decarboxylation of redox-active esters. The present reaction enables the preparation of functionalized gem-difluoroalkenes with the formation of sterically hindered C(sp3)–C(sp3) bonds under very mild reaction conditions, while tolerating many sensitive functional groups and requiring
trifluoromethylalkene derivatives. By using readily available allyl metallics as nucleophilic coupling partner, the present reaction enables an expedient construction of structurally diversified CF2-bridged 1,5-dienes. Furthermore, the exquisite selectivity observed in this transformation is revealed to be based on the underlying mechanism that consists of a cascade of nucleophilic SN2′ defluorinative
Synthesis of <i>gem</i>-difluoroalkenes <i>via</i> nickel-catalyzed allylic defluorinative reductive cross-coupling of trifluoromethyl alkenes with epoxides
nickel-catalyzed defluorinative reductive cross-coupling of trifluoromethyl alkenes with epoxides has been developed. Various substituted trifluoromethyl alkenes and epoxides were found to be suitable reaction substrates. This reaction enabled C(sp3)-C(sp3) bondconstruction through allylic defluorinative cross-coupling of trifluoromethyl alkenes under mild reaction conditions. This methodology was highly