Amine Activation: Synthesis of <i>N</i>-(Hetero)arylamides from Isothioureas and Carboxylic Acids
作者:Yan-Ping Zhu、Sergey Sergeyev、Philippe Franck、Romano V. A. Orru、Bert U. W. Maes
DOI:10.1021/acs.orglett.6b02247
日期:2016.9.16
A novel method for N-(hetero)arylamide synthesis based on rarely explored amine activation, rather than classical acid activation, is reported. The activated amines are easily prepared using a three-component reaction with commercial reagents. The new method shows a broad scope including challenging amides not (efficiently) accessible via classical protocols.
N-alkylation of amines by using secondary amides as the alkyl source was developed. A versatile type of carboxamide functioned as an N-alkylation reagent in the presence of an indium(III) catalyst and a hydrosilane to provide alkylated tertiary aminesefficiently. This amide-based catalytic N-alkylation strategy is considered to be a highly useful protocol to access unsymmetrical tertiary amines.
Efficient catalyst-free direct amidation of non-activated carboxylic acids from carbodiimides
作者:Mehmet Mart、Janusz Jurczak、Idris Karakaya
DOI:10.1039/d2ob01322c
日期:——
A novel and efficient catalyst- and activating agent-free amidationmethod via direct amidation of carboxylic acids where carbodiimides act as a reagent instead of an activating agent is reported. The reaction is conducted under non-traditional coupling conditions where a higher temperature is employed. Besides not using stoichiometric ratios of activating agent or catalyst, this approach is made even
The highly enantioselective synthesis of chiral amides was achieved by an asymmetric Wolff rearrangement. A bifunctional phosphoric acid catalyst not only expedited the transformation but also controlled the enantioselectivity. The developed method enables the asymmetric addition between potent nucleophilic reagents and ketene species and provides a new approach to chiral amides.