1,n-Diamines. Part 4: synthesis of 1-aryl-2-alkyl-1,4,5,6,7,8-hexahydro-1,3-diazocines

In this Letter we present the synthesis of hitherto unreported 1-aryl-2-alkyl-1,4,5,6,7,8-hexahydro-1,3-diazocines 1. Cyclic amidines 1 were synthesized by PPSE promoted ring closure of N-acyl-N′-arylpentamethylenediamines 2. The cyclodehydration reaction was performed under microwave irradiation in solvent-free conditions. Precursors 2 were prepared by selective functionalization of N-arylcadaverines 3.