Synthesis and properties of the novel (tetraazaporphinato)/(phthalocyaninato) manganese(III) – Pyridyl-substituted [60]fulleropyrrolidine dyads assembled through donor–acceptor bonding

Abstract

The self-assembly of (octakis(4-tret-butyl-phenyl)tetraazaporphyrinato) manganese(III) acetate, (AcO)MnTAP(4-tBuPh)8 or (octakis(3,5-di-tert-butylphenoxy)phthalocyaninato) manganese(III) acetate, (AcO)MnPc(3,5-di-tBuPhO)8 with 1′-N-methyl-2′-(pyridin-4-yl)pyrrolidino[3′,4':1,2][60]fullerene, PyC60 resulted in the formation of 1: 1 supramolecular system (dyad) in toluene was studied by the methods of chemical kinetics/thermodynamics and spectroscopy (UV-visible, fluorescence, IR and 1H NMR). It is found that the dyad formation mechanism depends on a macrocycle type. Theoretical calculations using B3LYP-D3/6-31G (d,p) basis set revealed stable complexation between (AcO)MnTAP(4-tBuPh)8/(AcO)MnPc(3,5-di-tBuPhO)8 and fulleropyrrolidine moiety. The dyad LUMO energy levels are predominantly spread on the C60 unit and the HOMO energy levels are mainly spread on the tetraazaporphyrin/phthalocyanine ring. The photoinduced electron transfer testing by the substantial quenching of the fluorescence emission of the manganese(III) complexes by axially bonded [60]fulleropyrrolidin gives the positive result that shows prospects of the studying dyads as the active layers in solar energy conversion devices. The photocurrent density of the manganese(III) tetraazaporphyrin/phthalocyanine films modifying the titanium electrode surface increases by factors of 2 when axially bonded [60]fulleropyrrolidine is present in the supramolecule structure.