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Updated: Aug 17, 2025

Preparation and Use of Carbonyl-decorated Carbenes in the Activation of White Phosphorus
Published on: October 3, 2014
Phosphine-catalyzed activation of cyclopropenones: a versatile C3 synthon for (3+2) annulations with unsaturated
Xin He1, Pengchen Ma1,2, Yuhai Tang1
1School of Chemistry, and Xi'an Key Laboratory of Sustainable Energy Materials Chemistry, Xi'an Jiaotong University Xi'an 710049 P. R. China.
Abstract:
We herein report a phosphine-catalyzed (3 + 2) annulation of cyclopropenones with a wide variety of electrophilic π systems, including aldehydes, ketoesters, imines, isocyanates, and carbodiimides, offering products of butenolides, butyrolactams, maleimides, and iminomaleimides, respectively, in high yields with broad substrate scope. An α-ketenyl phosphorous ylide is validated as the key intermediate, which undergoes preferential catalytic cyclization with aldehydes rather than stoichiometric Wittig olefinations. This phosphine-catalyzed activation of cyclopropenones thus supplies a versatile C3 synthon for formal cycloadditon reactions.
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