Non-hydrolytic chemoselective cleavage of Ugi tertiary amides: A mild access to N-substituted alpha-amino acid amides

摘要

N-Substituted alpha-amino acid amides can be easily obtained in two steps using the four-component Ugi reaction followed by chemoselective cleavage of the resulting tertiary amide. The use of the sacrificial acid, 2-hydroxymethylbenzoic acid is associated to shorter reaction times, higher yields, and safer and greener reaction conditions compared to strategies based on trifluoroacetic acid, a toxic and environmental hazardous reagent. The optimized procedure was easily scaled up to gram amounts. (C) 2018 Elsevier Ltd. All rights reserved.