A simple crab‐like cyclization procedure to prepare polyaza‐crowns and cyclams with one or two unsubstituted macroring nitrogen atoms or with a hydroxy group

A simple and convenient method to prepare polyaza‐crowns and cyclams containing one or two unsubstituted macroring nitrogen atoms or a hydroxy group is described. The process involves the reaction of a bis‐ chloroamide with a bis‐secondary amine followed by reduction of the cyclic diamide. The bis‐chloroamide resembles a crab with two reactive organochloride groups poised and ready to react, hence the term “crab‐like” cyclization. Nine new polyaza‐crowns and cyclams were prepared.