title: Development of biisoquinoline-based chiral diaminocarbene ligands: enantioselective SN2' allylic alkylation catalyzed by copper-carbene complexes.
abstract: Chiral biisoquinoline-based diaminocarbene ligands (BIQ) were designed to create a chiral environment extended toward the metal center, which was confirmed by an X-ray structure. The concise ligand synthesis is highlighted by a modified Bischler-Napieralski cyclization of bisamides prepared from readily available chiral phenethylamines, and allows easy variation of the stereodifferentiating groups. The cyclohexyl-BIQ-copper complex is an efficient catalyst for enantioselective SN2' allylic alkylation with Grignard reagents showing SN2' regioselectivity higher than 5:1 and enantioselectivity in the range of 68-77% ee.
authors.affiliation: Department of Chemistry, University of Florida, PO Box 117200, Gainesville, Florida 32611-7200, USA.
authors.forename: Hwimin
authors.initials: H
authors.lastname: Seo
authors.forename: Dimitri
authors.initials: D
authors.lastname: Hirsch-Weil
authors.forename: Khalil A
authors.initials: KA
authors.lastname: Abboud
authors.forename: Sukwon
authors.initials: S
authors.lastname: Hong