1,4-BIS(1,2,6-TRIPHENYL-4-PYRIDYL)BENZENE AS A NOVEL HYDROPHOBIC ELECTRON RELAY FOR DIHYDROGEN EVOLUTION IN PHOTOCATALYTIC SYSTEMS BASED ON LIPID VESICLES

1,4-Bis(1,2,6-triphenyl-4-pyridyl)benzene (''benzoviologen'') is an efficient lipophilic reversible electron relay, which can be used to build structurally organized molecular systems based on lipid vesicles for photocatalytic water cleavage. Benzoviologen has an advantage over the widely used conventional lipophilic viologens, since its reduced forms possess more negative reduction potentials. This promotes photostimulated transmembrane electron transfer and catalytic water reduction at neutral or even slightly basic pH. The kinetic properties of benzoviologen and its capacity to produce one- and two-electron-reduced forms were studied. The ability to couple vectorial transmembrane electron phototransfer with dihydrogen evolution from water over a dispersed Pd catalyst was proven experimentally.