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Updated: Jul 13, 2026

Preparation and Use of Carbonyl-decorated Carbenes in the Activation of White Phosphorus
Published on: October 3, 2014
Phosphine-catalyzed synthesis of highly functionalized coumarins
Christopher E Henry1, Ohyun Kwon
1Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, California 90095-1569, USA.
Abstract:
2-Styrenyl allenoates are converted into cyclopentene-fused dihydrocoumarins through phosphine-catalyzed regio- and diastereoselective [3 + 2] cycloadditions. Remarkably, changing the solvent from THF to benzene promotes the conversion of the 2-(2-nitrostyrenyl) allenoate into a tricyclic nitronate through a previously undocumented mode of phosphine catalysis. This nitronate was subjected to efficient face-, regio-, and exo-selective 1,3-dipolar cycloadditions to provide tetracyclic coumarin derivatives.
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