Palladium‐Catalyzed
<i>para</i>
‐Selective Alkylation of Electron‐Deficient Arenes
作者:Zhiwei Jiao、Li Hui Lim、Hajime Hirao、Jianrong Steve Zhou
DOI:10.1002/anie.201801967
日期:2018.5.22
Intermolecular alkylations of electron‐deficient arenes proceed with good para selectivity. Palladium catalysts were used to generate nucleophilic alkyl radicals from alkyl halides, which then directly add onto the arenes. The arene scope and the site of alkylation are opposite to those of classical Friedel–Crafts alkylations, which prefer electron‐rich systems.
A comprehensive study of the effects of spectator ligands, transition metals and lithium halide additives on the efficiency of iron, nickel and palladium-catalyzed cross-coupling reactions of cyclohexyl magnesium bromide with fluorinated bromobenzenes
作者:Adnan Dahadha、Wolfgang Imhof
DOI:10.3998/ark.5550190.p008.044
日期:——
(CH2)n, n = 1, 2, 3) have been used as the precatalysts. Palladium based catalysts give high yields of the coupling product with the Grignard reagent itself whereas lithium halides are needed as additives to achieve comparable efficiencies if nickel and iron catalysts are used. Yields also depend on the chain length of the bridging units and on the fact whether fluorine substituents are present in
Teaching an old carbocation new tricks: Intermolecular C–H insertion reactions of vinyl cations
作者:Stasik Popov、Brian Shao、Alex L. Bagdasarian、Tyler R. Benton、Luyi Zou、Zhongyue Yang、K. N. Houk、Hosea M. Nelson
DOI:10.1126/science.aat5440
日期:2018.7.27
find that these reactive intermediates undergo mild intermolecular carbon-carbon bond–forming reactions, including carbon-hydrogen (C–H) insertion into unactivated sp3 C–H bonds and reductive Friedel-Crafts reactions with arenes. Moreover, we conducted computational studies of these alkane C–H functionalization reactions and discovered that they proceed through nonclassical, ambimodal transition structures