A Phosphonium Ylide as a Ligand for [3 + 2] Coupling Reactions of Epoxides with Heterocumulenes under Mild Conditions.

J Org Chem

Department of Materials Chemistry, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan.

Published: August 2020

The potential of carbonyl-stabilized phosphonium ylides as ligands for novel catalysis was explored. We found that the combination of phosphonium ylides and metal halide salts efficiently catalyzed the reaction of epoxides with carbon dioxide under mild conditions. Five-membered cyclic carbonates, including disubstituted cyclic carbonates, were obtained in good yields with the use of 1 atm of carbon dioxide at 35 °C. Terminal epoxides could be converted to -aryl oxazolidinones in the reaction with isocyanates under a similar catalytic system.

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http://dx.doi.org/10.1021/acs.joc.0c01101DOI Listing

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