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Metal-Free Brønsted Acid-Catalyzed Rearrangement of δ-Hydroxyalkynones to 2,3-Dihydro-4H-pyran-4-ones: Total Synthesis of Obolactone and a Catechol Pyran Isolated from Plectranthus sylvestris

Sachin P. Gholap, Dashrath Jangid, Rodney A. Fernandes*

*Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India, Email:

S. P. Gholap, D. Jangid, R. A. Fernandes, J. Org. Chem., 2019, 84, 3537-3551.

DOI: 10.1021/acs.joc.8b03141 (free Supporting Information)

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A metal-free, pTsOH-catalyzed intramolecular rearrangement of δ-hydroxyalkynones provides substituted 2,3-dihydro-4H-pyran-4-ones. The rearrangement occurs with high regioselectivity under mild conditions.

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ID: J42-Y2019