The formation of complexes between aza-derivatives of crown ethers and primary alkylammonium salts. Part 5. Chiral macrocyclic diamines

Abstract

Syntheses of three types of chiral macrocyclic diamines, analogous to crown ethers, are described. The chirality of these systems is based, in one case, upon the plane of chirality of paracyclophane systems and, in the other two cases, upon the axis of chirality of bridged biphenyls. Two methods are described for the measurement of chiral selectivity in the formation of complexes between these chiral macrocyclic host molecules and chiral guest primary alkylammonium salts. Both methods use n.m.r. Spectrometry, a single-phase system, a racemic chiral host and (R)- and (RS)-guest salts. The first method is suitable for both optically labile and optically stable hosts and the second method is only suitable for optically labile host species.