A Facile Synthesis of Carboxamides by Dehydration Condensation Between Free Carboxylic Acids and Amines Using O,O'-Di(2-pyridyl) Thiocarbonate as a Coupling Reagent
A Convenient Method for the Preparations of Carboxamides and Peptides by Using Di(2-pyridyl) Carbonate and<b><i>O</i></b>,<b><i>O</i></b><sup>′</sup>-Di(2-pyridyl) Thiocarbonate as Dehydrating Reagents
di(2-pyridyl) carbonate (DPC) or O,O′-di(2-pyridyl) thiocarbonate (DPTC) in the presence of a catalytic amount of 4-(dimethylamino)pyridine (DMAP). The formation of 2-pyridyl esters, key intermediates of the reaction, from carboxylic acids by using DPC proceeded faster than by using DPTC; therefore, the former carbonate is more efficiently employed in the above condensation reactions.
The effective use of substituted benzoic anhydrides for the synthesis of carboxamides
作者:Isamu Shiina、Yo-ichi Kawakita
DOI:10.1016/j.tet.2004.03.066
日期:2004.5
Various carboxamides are synthesized from the corresponding carboxylic acids and amines with high product-selectivities using 2-methyl-6-nitrobenzoic or 2,4,6-trichlorobenzoic anhydride in the presence of 4-(dimethylamino)pyridine. (C) 2004 Elsevier Ltd. All rights reserved.