X-Ray Crystal Structures of trans -6,13-Dimethyl-6,13-Diamino-1,4,8,11-Tetraazacyclotetradecane.6HCl.2H 2 O and its Condensation Product with Pyridine-2-Carboxaldehyde

Abstract

The X-ray crystal structures of trans-6,13-dimethyl-6,13-diamino-1,4,8,11-tetraazacyclotetradecane hexahydrochloride dihydrate (trans-diammac.6HCl.2H₂O) and the product 1 derived by condensation of trans-diammac with pyridine-2-carboxaldehyde, have been determined. For 1 intramolecular attack of macrocycle amine nitrogen atoms on the C=N bonds of the intermediate diimine gives a ring-closed tautomeric form, which comprises two imidazolidine rings fused to the macrocycle.