title: A stereoselective intramolecular 1,3-dipolar nitrone cycloaddition for the synthesis of substituted chromanes.
abstract: A stereoselective intramolecular 1,3-dipolar nitrone cycloaddition useful in the synthesis of chromanes is described. The reaction relies on the use of a chiral auxiliary on the nitrone partner. Key to the success of the reaction is the choice of auxiliary and the choice of Lewis acid catalyst. Utilizing an auxiliary with a pendant coordinating group, and Zn(OTf)(2) as the Lewis acid, diastereoselectivities up to 22:1 could be achieved.
authors: Medicinal Chemistry Research, Structural, Analytical, and Medicinal Chemistry, Pharmacia & Upjohn, Pharmacia Corp., Kalamazoo, Michigan 49009, USA.
authors: Qian
authors: Q
authors: Zhao
authors: Fusen
authors: F
authors: Han
authors: Donna L
authors: DL
authors: Romero