Visible-Light-Promoted Cascade Cyclization of 3-Ethynyl-[1,1'-biphenyl]-2-Carbonitriles with Unsaturated
Yu-Song Ran1, Bo Jiang1, Yun-Tao Shen1
1Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, P. R. China.
Abstract:
A visible-light-promoted cascade cyclization of 3-ethynyl-[1,1'-biphenyl]-2-carbonitriles with unsaturated α-bromocarbonyls for the synthesis of tetrahydrobenzo[mn]cyclopenta[b]acridines is described. Three C(sp3)-C(sp2) bonds, one C(sp2)-N bond, and three cycles can be formed in a single reaction through the addition of a C-centered radical to the carbon-carbon triple bond and three radical cyclizations. This reaction features mild conditions, wide substrate scope, and high bond-forming efficiency.
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