title: Enantioselective cyclopropanation of enals by oxidative N-heterocyclic carbene catalysis.
abstract: Carbene catalysed redox activation of α,β-unsaturated aldehydes is applied for generation of α,β-unsaturated acyl azoliums which undergo cyclopropanation upon reaction with a sulfur ylide and an alcohol to give the corresponding cyclopropanecarboxylic acid esters. With chiral carbenes good to excellent diastereo and enantioselectivities are obtained.
authors.affiliation: Institute of Organic Chemistry, NRW Graduate School of Chemistry, Westfälische Wilhelms-University Münster, Corrensstrasse 40, 48149 Münster, Germany.
authors.forename: Anup
authors.initials: A
authors.lastname: Biswas
authors.forename: Suman
authors.initials: S
authors.lastname: De Sarkar
authors.forename: Ludger
authors.initials: L
authors.lastname: Tebben
authors.forename: Armido
authors.initials: A
authors.lastname: Studer
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D002384:Catalysis; D003521:Cyclopropanes / Q000737:chemistry*; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D010084:Oxidation-Reduction; D013237:Stereoisomerism; D013455:Sulfur / Q000737:chemistry
chemical_list: D000447:Aldehydes; D003521:Cyclopropanes; C030011:carbene; D013455:Sulfur; C030797:cyclopropane; D008697:Methane