title: Direct synthesis of esters and amides from unprotected hydroxyaromatic and -aliphatic carboxylic acids.
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.
authors.affiliation: Center for Heterocyclic Compounds, University of Florida, Department of Chemistry, Gainesville, Florida 32611-7200, USA. katritzky@chem.ufl.edu
authors.forename: Alan R
authors.initials: AR
authors.lastname: Katritzky
authors.forename: Sanjay K
authors.initials: SK
authors.lastname: Singh
authors.forename: Chunming
authors.initials: C
authors.lastname: Cai
authors.forename: Sergey
authors.initials: S
authors.lastname: Bobrov