Development of quadrupolar engaging auxiliaries as novel gearing elements for macrocyclization

Abstract

The formation of various macrocyclic cyclophanes via ring-closing olefin metathesis is possible through the use of a pendant pentafluorobenzyl ester group. A quadrupolar interaction between the cyclophane core and the auxiliary is proposed to act as a gearing element facilitating cyclization. The development of these noncovalent interactions as gearing elements as well as the investigation of the effect of the site of metathesis upon the macrocyclization process is described. © 2006 IUPAC.