title: Esterification Catalysis by Pyridiniump-Toluenesulfonate Revisited-Modification with a Lipid Chain for Improved Activities and Selectivities.
abstract: The lipid analogues of pyridiniump-toluenesulfonate (PPTS) were examined for catalyzing the condensation of an equimolar mixture of carboxylic acids and alcohols under mild conditions without removal of water. Although PPTS is a poor catalyst, the introduction of a lipid chain and nitro group significantly improved the activity of PPTS and led to selectivity at suppressing elimination side reactions of alcohols. 2-Oleamido-5-nitro-pyridiniump-toluenesulfonate (6) is a lead catalyst that promoted various esterification reactions with yields up to 99%.
authors.affiliation: Department of Chemistry and Biochemistry, Southern Illinois University, 1245 Lincoln Drive, Carbondale, Illinois 62901-4409.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Huimin
authors.initials: H
authors.lastname: Liu
authors.forename: Shaoyi
authors.initials: S
authors.lastname: Xu
authors.forename: Yong
authors.initials: Y
authors.lastname: Gao
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