A New Versatile Synthesis of Macrotricyclic Tetraazacycloalkane‐Based Ligands from Bis‐aminal Derivatives

Abstract

Abstract A new powerful synthesis of symmetrical (two‐step) or dissymmetrical (three‐step) macrotricyclic cyclen‐ or cyclam‐based ligands is reported. In this procedure, the starting materials are bis‐aminals derived from condensation of cyclen or cyclam with glyoxal. The two macrocyclic subunits are linked by two aromatic spacers through nitrogen atoms. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)