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Updated: Aug 15, 2025

Synthesis of Esters Via a Greener Steglich Esterification in Acetonitrile
Published on: October 30, 2018
Repurposing amine and carboxylic acid building blocks with an automatable esterification reaction
Andrew McGrath1, Rui Zhang2, Khadija Shafiq1
1Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI 48109, USA. tcernak@med.umich.edu.
Abstract:
New methodologies to unite amines and carboxylic acids that complement the popular amide coupling can significantly expand accessible chemical space if they yield products distinct from the classic R-NHC(O)-R' amide arrangement. Here we have developed an amine-acid esterification reaction based on pyridinium salt activation of amine C-N bonds to create products of type R-OC(O)-R' upon reaction with alkyl and aryl carboxylic acids. The protocol is robust and facile as demonstrated by automation on open-source robotics.
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