New family of polydentate tetrazole-pyrazoline ligands prepared by the azido-Ugi reaction

A new family of ligands containing fragments of tetrazole and pyrazoline was prepared in one step by the efficient azido-Ugi reaction of N-(arylidene)pyrazolinium salts with isocyanides and sodium azide in up to 86% yield. The utility of the ligands was demonstrated by the synthesis of coordination complexes with Cu and Pd.