title: Asymmetric synthesis of polysubstituted 4-amino- and 3,4-diaminochromanes with a chiral multifunctional organocatalyst.
abstract: A series of multifunctional catalysts with two chiral diaminocyclohexane units were developed and successfully applied in the asymmetric oxa-Michael-aza-Henry cascade reaction of salicylaldimines with nitroolefins. This approach provides a simple and efficient entry to polysubstituted chiral 4-aminobenzopyrans with three consecutive stereocenters and in high yield (up to 97%) with excellent stereoselectivity (up to 98% ee and >99:1 dr). Facile access to the nonsymmetric optically pure 3,4-diaminochromanes was also obtained.
authors.affiliation: School of Chemistry and Chemical Engineering, Southwest University , Chongqing 400715, PR China.
authors.forename: Wenduan
authors.initials: W
authors.lastname: Hou
authors.forename: Bo
authors.initials: B
authors.lastname: Zheng
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.forename: Yungui
authors.initials: Y
authors.lastname: Peng
mesh_terms: D002384:Catalysis; D002839:Chromans / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D002839:Chromans