Regioselective Functionalization of 3-Hydroxy-pyridine Carboxylates by Neighboring Group Assistance
K Philip Wojtas1, Jin-Yong Lu1, Daniel Krahn1
1Friedrich-Schiller-Universität, Institut für Organische Chemie und Makromolekulare Chemie, Humboldtstraße 10, 07743, Jena, Germany.
Abstract:
Regioselective hydrolysis, transesterification, and aminolysis of unactivated, highly substituted pyridine esters were realized under mild conditions by employing neighboring group assisted catalysis. Excellent yields were achieved without active removal of the alcohol byproduct. Regioselective aminolysis had a considerable substrate scope ([hetero]aryl, alkyl and amino acid). A mechanism involving assistance by the deprotonated phenolic OH-group is suggested for hydrolysis and transesterification.
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