Synthesis of 1,5-substituted iminodibenzo[b,f][1,5]diazocine, an analogue of Troger's base

A method for the synthesis of 1,5-disubstituted iminodibenzo[b,f][1,5]diazocines is presented. The synthesis is achieved by the metal-free cyclization of 2-aminophenyl ketimines using the corresponding 2-aminophenyl ketone as the catalyst. The synthesis gives new insight into the mechanism of formation of this class of compounds. The presence of potential sites for hydrogen-bond formation and two aromatic bromine atoms available for functionalization make these targets attractive for further development in supramolecular chemistry. The structure of the complex derived from the iminodibenzo[b,f][1,5]diazocine and PdCl2 was determined by X-ray crystallography.