N-Acylation of 5-Substituted Indoles with Carboxylic Acids via DCC Coupling

Abstract

A method for the N-acylation of 5-substituted indoles with carboxylic acids using DCC and DMAP is presented. High yields were obtained when an electron-withdrawing group was present at C-5, however the method was less effective with a C-5 electron-donating group.

Key words

N-acylation - indoles - carboxylic acids - DCC coupling - DMAP

References

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  Indole ester formation by DCC/DMAP coupling of carboxylic acids with alcohols or phenols is reported in this paper. N-Acylation of the derivatives was achieved, however, via indolide formation with sodium hydride followed by reaction with an acid chloride.

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