A practical method for the acylation of 2-imidazolidinone and 2-oxazolidinone chiral auxiliaries with 2-bromoacyl halides

SX Candeias, K Jenkins, ASC Ribeiro…

Index: Candeias; Jenkins; Ribeiro; Afonso; Caddick Synthetic Communications, 2001 , vol. 31, # 21 p. 3241 - 3254

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Citation Number: 5

Abstract

Optimised conditions for the acylation of (S)-4-(1-methylethyl)-oxazolidin-2-one 4,(R)-4- phenyloxazolidin-2-one 5 and 4-(R),(5 S)-1, 5-dimethyl-4-phenylimidazolidin-2-one 3 with 2- bromoacyl halides were developed. For imidazolidin-2-one 3 the optimum conditions require the use of the hindered bases 2, 6-di-t-butylpyridine or 2, 6-lutidine in order to reduce the ketene formation which has a strong preference for O-acylation.