Synthesis of Functionalized Benzo[b]furans via Oxidative Cyclization of o-Cinnamyl Phenols
Mohammad Rehan, Rajender Nallagonda, Braja Gopal Das, Tannu Meena and Prasanta Ghorai*
*Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Bhopal-462066, India, Email: pghoraiiiserb.ac.in
M. Rehan, R. Nallagonda, B. G. Das, T. Meena, P. Ghorai, J. Org. Chem., 2017, 82, 3411-3424.
DOI: 10.1021/acs.joc.6b02752 (free Supporting Information)
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A regioselective 5-exo-trig intramolecular oxidative cyclization of ortho-cinnamyl phenols using [PdCl2(CH3CN)2] as catalyst and benzoquinone as an oxidant provides functionalized 2-benzyl benzo[b]furans. Further, a one-pot, sequential synthesis of ortho-cinnamyl phenols, starting from readily available alcohols and phenols, followed by Pd-catalyzed oxidative annulation, has also been developed.
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