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Carbonyl Umpolung Reactivity of Enals: NHC-Catalyzed Synthesis of Aldol Products via Epoxide Ring Opening

Lal Dhar S. Yadav*, Santosh Singh, Vijai K. Rai

*Green Synthesis Lab, Department of Chemistry, University of Allahabad, Allahabad 211 002, India, Email:

L. D. S. Yadav, S. Singh, V. K. Rai, Synlett, 2010, 240-246.

DOI: 10.1055/s-0029-1218563

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A N-heterocyclic carbene catalyzed the synthesis of aldol products in good yields involving carbonyl umpolung of enals to form nucleophiles, which attack electrophilic terminal epoxides, regioselectively. These aldols have been used in a facile and highly cis-selective synthesis of tetrahydropyran-4-ones.

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Key Words

N-heterocyclic carbenes, organocatalysis, umpolung, epoxides, aldols, enones, tetrahydropyran-4-ones

ID: J60-Y2010-0120