Photocatalytic Oxidative Heterocyclization of Semicarbazones: An Efficient Approach for the Synthesis of 1,3,4-Oxadiazoles
Ritu Kapoorr, Sachchida N. Singh, Shubhangi Tripathi, Lal Dhar S. Yadav*
*Green Synthesis Lab, Department of Chemistry, University of Allahabad, Allahabad 211 002, India, Email: ldsyadavhotmail.com
R. Kapoorr, S. N. Singh, S. Tripathi, L. D. S. Yadav, Synlett, 2015, 26, 1201-1206.
DOI: 10.1055/s-0034-1380493 (free Supporting Information)
A highly efficient eosin Y catalyzed oxidative heterocyclization of semicarbazones was established under visible-light photoredox catalysis using CBr4 as a bromine source. The protocol renders a rapid, mild, and efficient access to valuable 5-substituted 2-amino-1,3,4-oxadiazoles in an operationally simple way utilizing visible light and atmospheric oxygen.
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