Chemoselective acylation of 2-amino-8-quinolinol in the generation of C2-amides or C8-esters

Abstract

Two different ways to carry out the chemoselective acylation of 2-amino-8-quinolinol with unique features to generate C2-amides or C8-esters were developed. The coupling reaction with a variety of carboxylic acids using EDCI and DMAP provided C8-ester derivatives, whereas N-heteroaromatic acids were not introduced on the C8-hydroxy group, but rather on the C2-amino group under the same conditions. To obtain C2-amides selectively, the anionic nucleophile from 2-amino-8-quinolinol was treated with less reactive acyl imidazolides or esters.