Ring-closing metathesis approach for the synthesis of optically active l-proline-based macrocycles

Abstract

Chiral macrocyclic compounds find many interesting applications in supramolecular chemistry, such as in chiral discrimination and chiral catalysis. In this study, the synthesis of novel optically active macrocyclic compounds based on l-proline is reported. The key step in the synthetic strategy is the utility of a ring-closing metathesis (RCM) technique. The synthesized macrocyclic compounds have been characterized by NMR, mass analysis, and single crystal X-ray crystallography. The application of these macrocyclic compounds as enantiodiscriminating agents have been demonstrated using (rac)-mandelic acid (2-hydroxy-2-phenylacetic acid) as a model example.