Synthesis of 3,4-Disubstituted 2H-Benzopyrans through C-C Bond Formation via Electrophilic Cyclization
Shilpa A. Worlikar, Tanay Kesharwani, Tuanli Yao and Richard C. Larock*
*Department of Chemistry, Iowa State University, Ames, Iowa 50011, Email: larockiastate.edu
S. A. Worlikar, T. Kesharwani, T. Yao, R. C. Larock, J. Org. Chem., 2007, 72, 1347-1353.
DOI: 10.1021/jo062234s (free Supporting Information)
see article for more reactions
A mild, electrophilic cyclization of substituted propargylic aryl ethers by I2, ICl, and PhSeBr produces 3,4-disubstituted 2H-benzopyrans in excellent yields. This methodology tolerates various functional groups, such as methoxy, alcohol, aldehyde, and nitro groups.
see article for more examples