Synthesis of chiral azamacrocycles using the bis(α‐chloroacetamide)s derived from chiral 1,2‐diphenylethylenediamine

Abstract

AbstractOptically active diphenyl‐substituted tetraaza‐12‐crown‐4 diamide (10), tetraaza‐15‐crown‐5 diamide (12), tetraaza‐18‐crown‐6 diamide (11), and hexaaza‐18‐crown‐6 diamide (9) ligands were prepared by treating the appropriate secondary diamines with the (R,R)‐ and (S,S)‐ forms of 1,2‐bis(N‐methyl‐α‐chloracetamido)‐1,2‐diphenylethane (20). Macrocyclic diamides 9 and 10 were reduced to form the optically active diphenyl‐substituted hexaaza‐18‐crown‐6 (13) and tetraaza‐12‐crown‐4 (14), respectively. Reduction of macrocyclic diamide ligands 11 and 12 gave a complex mixture of products from which the desired tetraaza‐15‐crown‐5 and 18‐crown‐6 compounds could not be isolated. Dichloride 20 was prepared by treating the chiral forms of 1,2‐ diphenylethylenediamine with chloroacetic anhydride or chloroacetyl chloride. The crystal structures for the (R,R)‐form of dichloride 20 and the (S,S)‐forms of macrocycles 10 and 11 are reported.