Direct synthesis of esters and amides from unprotected hydroxyaromatic and -aliphatic carboxylic acids

Alan R Katritzky; Sanjay K Singh; Chunming Cai; Sergey Bobrov

doi:10.1021/jo052293q

Direct synthesis of esters and amides from unprotected hydroxyaromatic and -aliphatic carboxylic acids

J Org Chem. 2006 Apr 28;71(9):3364-74. doi: 10.1021/jo052293q.

Authors

Alan R Katritzky¹, Sanjay K Singh, Chunming Cai, Sergey Bobrov

Affiliation

¹ Center for Heterocyclic Compounds, University of Florida, Department of Chemistry, Gainesville, Florida 32611-7200, USA. katritzky@chem.ufl.edu

PMID: 16626115
DOI: 10.1021/jo052293q

Abstract

A facile method for the activation of hydroxy-substituted carboxylic acids using benzotriazole chemistry without prior protection of the hydroxy substituents is presented. The N-acylbenzotriazole intermediates 2a-g, 6a-d, and 9a-c have been used for high-yielding synthesis of both aliphatic (3a-l) and aromatic (7a-h, 10a-f) hydroxy carboxamides. High yields of aromatic hydroxy esters 12a-h and 13a-i were obtained using either neat alcohols in neutral microwave conditions or nucleophilic alkoxides and the intermediate N-(arylacyl)benzotriazoles. Moderate yields were obtained in the case of aliphatic hydroxy esters 11a,b and thiolesters 11e-g from the intermediates 2a-c.