In an aqueous dimethyl sulfoxide (DMSO) solution of triethanolamine (TEOA), the photosensitizer of the title complex (1), and 1,1'-dimethyl-4,4'-bipyridinium dichloride (MVCl2), MV•+radicals were formed upon irradiation with visible light; the photoreduction proceeded with light from both the B- (340 nm) and Q- (674 nm) band wavelengths of 1.The photoreduction of hydrogencarbonate to methane was performed in an aqueous DMSO solution of an electron donor, 1, MVCl2, and ruthenium colloid upon irradiation with visible light. Ethylene was also photoreduced to ethane upon the irradiation of an aqueous solution of an electron donor, 1, MVCl2, and palladium colloid.