Synthesis and characterization of hexa-coordinated Sn(IV) complexes of meso-aryl dipyrrins.

Our successful synthesis of the first examples of Sn(IV) complexes of meso-aryl dipyrrins is reported. Sn(IV) dipyrrins are synthesized by treating meso-aryl dipyrrins with readily available SnCl2·2H2O in pyridine at reflux temperature and isolated as pure complexes by recrystallization. The X-ray structure revealed that the complex is hexa-coordinated and the Sn(IV) ion is coordinated to two dipyrrin units and two chlorides with overall appearance of a butterfly like structure. The complexes are stable in solution and characterized by spectral and electrochemical techniques.