title: Organocatalytic one-pot 1,4-/1,6-/1,2-addition sequence for the stereocontrolled formation of six consecutive stereocenters.
abstract: An unprecedented stereoselective organocatalytic one-pot 1,4-/1,6-/1,2-addition sequence between β-dicarbonyl compounds, β-nitroalkenes and 4-nitro-5-styrylisoxazoles sequentially catalyzed by low loading of a squaramide catalyst and an achiral base has been developed. The protocol opens an efficient entry to isoxazole bearing cyclohexanes with six consecutive stereogenic centers including one tetrasubstituted carbon in good yields and excellent diastereo- and enantioselectivities.
authors.affiliation: Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany. enders@rwth-aachen.de.
authors.forename: Pankaj
authors.initials: P
authors.lastname: Chauhan
authors.forename: Suruchi
authors.initials: S
authors.lastname: Mahajan
authors.forename: Gerhard
authors.initials: G
authors.lastname: Raabe
authors.forename: Dieter
authors.initials: D
authors.lastname: Enders