Reaction of isonitriles with carboxylic acids in a cavitand: observation of elusive isoimide intermediates

Abstract

A deep cavitand with an inwardly directed carboxylic acid function reacts with small aliphatic isonitriles to form N-acyl formamides inside the cavity. The unique isolation and stabilization of covalently bound guests within the structured environment of the cavitand allows for observation of the labile O-acyl isoimide intermediate using conventional spectroscopic methods.