N-Heterocyclic carbene–chromium-catalyzed alkylative cross-coupling of benzamide derivatives with aliphatic bromides
作者:Jinghua Tang、Pei Liu、Xiaoming Zeng
DOI:10.1039/c8cc05026k
日期:——
Described here is a chromium-catalyzed alkylative cross-coupling of benzamide derivatives with aliphatic electrophiles under mild conditions. This reaction was promoted by a low-cost and air-stable chromium(III) chloride salt combined with an N-heterocyclic carbene ligand and phenylmagnesium bromide as a reductant, and probably occurred with low-valent chromium involved in the catalytic cleavage of
Rhodium‐Catalyzed Alkylation of C−H Bonds in Aromatic Amides with Non‐activated 1‐Alkenes: The Possible Generation of Carbene Intermediates from Alkenes
The alkylation of C−H bonds (hydroarylation) in aromatic amides with non‐activated 1‐alkenes using a rhodium catalyst and assisted by an 8‐aminoquinoline directing group is reported. The addition of a carboxylic acid is crucial for the success of this reaction. The results of deuterium‐labeling experiments indicate that one of deuterium atoms in the alkene is missing, suggesting that the reaction does
Rh(I)-Catalyzed Alkylation of <i>ortho</i>-C–H Bonds in Aromatic Amides with Maleimides
作者:Qiyuan He、Takuma Yamaguchi、Naoto Chatani
DOI:10.1021/acs.orglett.7b02135
日期:2017.9.1
An alkylation of C–H bonds with maleimides by a rhodium-catalyzed reaction of aromatic amides containing an 8-aminoquinoline moiety as the directing group is reported. Various N-substituents in the maleimide, including methyl, ethyl, cyclohexyl, benzyl, and phenyl groups and even H, are applicable to the reaction. The reaction is highly regioselective at the less hindered ortho-C–H bond when meta-substituted
A unique C–H allylation has been discovered with unbiased aliphatic olefins. An intimate M–L affiliation between a high-valent cobalt catalyst and amino-quinoline derived benzamides has been found to be crucial for this unprecedented selectivity. An exemplary set of aliphatic olefins, high yields coupled with excellent regio- and stereoselectivity, and wide functional group tolerances are noteworthy