Regioselective Formation of Enol Esters from the Ruthenium-Catalyzed Markovnikov Addition of Carboxylic Acids to Alkynes
Janine Jeschke, Christian Gäbler and Heinrich Lang*
*Technische Universität Chemnitz, Faculty of Natural Sciences, Institute of Chemistry, Inorganic Chemistry, 09107 Chemnitz, Germany, Email: heinrich.langchemie.tu-chemnitz.de
J. Jeschke, C. Gäbler, H. Lang, J. Org. Chem., 2016, 81, 476-484.
Ruthenium complexes were successfully applied in highly regioselective Markovnikov additions of carboxylic acids to terminal alkynes, yielding valuable enol esters. Selectivity and activity could be further improved by the addition of catalytic amounts of AgOTf. A broad range of simple as well as electronically or sterically challenging substrates could be isolated in good to excellent yields with high regioselectivity and under mild reaction conditions.
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