A new method for the synthesis of carboxamides and peptides using 1,1′-carbonyldioxydi[2(1H)-pyridone] (CDOP) in the absence of basic promoters
作者:Isamu Shiina、Yo-ichi Kawakita
DOI:10.1016/s0040-4039(03)00063-7
日期:2003.2
Various carboxamides or peptides are synthesized from the corresponding carboxylic acids and amines or α-amino acids using 1,1′-carbonyldioxydi[2(1H)-pyridone]. The reaction proceeds in the absence of basic promoters such as triethylamine or 4-(dimethylamino)pyridine, therefore, the undesired racemization does not occur at all in the segment coupling producing Z-Gly-Phe-Val-OMe and Z-Phe-Val-Ala-OMe
Tetrakis(pyridin-2-yloxy)silane [Si(OPy)4] is easily prepared by trans-silylation between silicon tetrachloride and trimethyl(pyridin-2-yloxy)silane in the molar ratio of 1:4. This novel reagent is effectively employed as a mild dehydrating reagent in forming various carboxamides from the corresponding carboxylic acids and amines that involve secondary or tertiary alkyl substituted ones in good to high yields without using any basic promoters such as tertiary amines or 4-(dimethylamino)pyridine.