New high yield syntheses of cyclams using the crab-like cyclization reaction

Article abstract of DOI:10.1016/S0040-4039(00)88730-4

A new high yield method to synthesize cyclams containing one or two unsubstituted ring nitrogen atoms and with alkyl groups on the remaining ring nitrogen atoms is presented. The method consists of the ring closure reaction of a crab-like bis-α-chloroamide with a bis-secondary amine followed by reduction. The amide functions of the starting material act as protecting groups for the protons on the amide nitrogen atoms.