Visible-Light-Triggered Oxidative C-H Aryloxylation of Phenolic Amidines; Photocatalytic Preparation of 2-Aminobenzoxazoles
Vishnu P. Srivastava*, Lal Dhar S. Yadav*
*Green Synthesis Lab, Department of Chemistry, University of Allahabad, Allahabad 211 002, India, Email: prabhaker7777yahoo.com, ldsyadavhotmail.com
V. P. Srivastava, L. D. S. Yadav, Synlett, 2013, 24, 2758-2762.
DOI: 10.1055/s-0033-1340150 (free Supporting Information)
Visible light efficiently mediates a mild intramolecular oxidative cyclization of o-hydroxy-N-aryl-N,N-dialkylformamidines leading to 2-aminobenzoxazole derivatives in excellent yields in the presence of only 1 mol% tris(2,2′-bipyridine)ruthenium(II) as a photoredox catalyst and air as terminal oxidant.
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