Direct Synthesis of Amides from Carboxylic Acids and Amines Using B(OCH<sub>2</sub>CF<sub>3</sub>)<sub>3</sub>
作者:Rachel M. Lanigan、Pavel Starkov、Tom D. Sheppard
DOI:10.1021/jo400509n
日期:2013.5.3
range of amines. In most cases, the amide products can be purified by a simple filtration procedure using commercially available resins, with no need for aqueous workup or chromatography. The amidation of N-protected amino acids with both primary and secondary amines proceeds effectively, with very low levels of racemization. B(OCH2CF3)3 can also be used for the formylation of a range of amines in good
An eco-benign and highly efficient procedure for N-acylation catalyzed by heteropolyanion-based ionic liquids using carboxylic acid under solvent-free conditions
An eco-benign and highly efficient route for N-acylation of amines has been developed by treating amines with corresponding carboxylic acids in the presence of 2 mol % of heteropolyanion-based ionic liquids as catalysts under solvent-free conditions. This practical reaction could tolerate a wide range of substrates. Thus, various N-acylation products including N-acyl alpha-amino acid derivatives were obtained in moderate to excellent yields at 70 degrees C to 120 degrees C. Moreover, recycling studies revealed that heteropolyanion-based ionic liquids were easily reusable for this N-acylation. This method provides a green and much improved protocol over the existing methods.(c) 2014 Elsevier Ltd. All rights reserved.