Pd(II)-Catalyzed Alkylation of Tertiary Carbon via Directing-Group-Mediated C(sp<sup>3</sup>)–H Activation: Synthesis of Chiral 1,1,2-Trialkyl Substituted Cyclopropanes
A Pd(OAc)2-catalyzed alkylation reaction of the tertiary carbon of chiral cyclopropane substrates with alkyl iodides and bromides via C(sp3)–H activation has been developed. This is an elusive example of a C–H activation-mediated alkylation of tertiary carbon to effectively construct a quaternary carbon center. The alkylation proceeded with various alkyl halides, including those of functional groups
Stereoselective Synthesis of Diazabicyclic β-Lactams through Intramolecular Amination of Unactivated C(sp<sup>3</sup>)–H Bonds of Carboxamides by Palladium Catalysis
An efficient C(sp3)–H bond activation and intramolecular amination reaction via palladiumcatalysis at the β-position of carboxyamides to make β-lactams was described. The investigation of the substrate scope showed that the current reaction conditions favored activation of the β-methylene group. Short sequences were developed for preparation of various diazabicyclic β-lactam compounds with this method
Copper catalysed amidation of aryl halides through chelation assistance
作者:Subban Kathiravan、Shishir Ghosh、Graeme Hogarth、Ian A. Nicholls
DOI:10.1039/c4cc09940k
日期:——
Using 8-aminoquinoline-based alkyl and aryl carboxamides, the direct N-arylation was achieved in good yields in the presence of a copper catalyst via chelation-assisted reaction.
A copper‐catalyzed remoteC−Hamination of 8‐aminoquinoline scaffolds on the C5 position is described. The protocol employs commercially available N‐fluorobenzenesulfonimide (NFSI) as the amination reagent and shows broad substrate scope, providing various 5‐aminated quinolines in moderate to excellent yields under mild conditions. These reactions feature complete regioselectivity, operational simplicity
Experimental and Computational Studies on Remote γ-C(sp<sup>3</sup>)–H Silylation and Germanylation of Aliphatic Carboxamides
作者:Arghya Deb、Sukriti Singh、Kapileswar Seth、Sandeep Pimparkar、Bangaru Bhaskararao、Srimanta Guin、Raghavan B. Sunoj、Debabrata Maiti
DOI:10.1021/acscatal.7b03056
日期:2017.12.1
germanylation of aliphaticcarboxylicacids is reported. Bidentate 8-aminoquinoline as the directing group was found to stabilize the six-membered palladacycle. A variety of aliphaticcarboxylicacids and amino acids were silylated and germanylated in good yields and high diasteroselectivities. Detailed mechanistic studies involving isolation of a Pd(II) intermediate, determination of the reactionrate and order