A Chiral Macrocycle for the Synthesis of Both Mechanically Planar Chiral Rotaxanes and Catenanes in Excellent Enantiopurity

Abstract

Active-template auxiliary methodologies have previously been developed for the stereoselective synthesis of chiral interlocked molecules in which the mechanical bond provides the sole stereogenic unit. To date however, the covalent auxiliary has been included in the half-axle components (rotaxanes) or pre-macrocycle components (catenanes), and thus mechanically chiral rotaxane and catenane syntheses rely on different chiral components. Here we present a single, simple amino acid-derived macrocycle that mediates the formation of both catenanes and rotaxanes in excellent stereoselectivity. We demonstrate the flexibility of our approach through the stereoselective synthesis of all three isomers of a co-conformationally mechanically planar chiral [3]rotaxane.