摘要:
Water-soluble viologen-linked zinc porphyrin (ZnP(C4VC4)(4)) and bisviologen-linked zinc porphyrin (ZnP(C4VAC4VB)(4)) were synthesized. In ZnP(C4VAC4VB)4(,) two viologens (butylviologen and 1-benzyl-1-butylvislogen) are connected with the tetrakis-(4-pyridyl)-zinc porphyrin via a methylene chain (-(CH2)(4-)), so as to produce a gradient of redox potential in the molecule. The photochemical and electrochemical properties of ZnP(C4VAC4VB), and ZnP(C4VC4)(4) were investigated by using the absorption spectra, the fluorescence spectra and the cyclic voltammetric measurement. The photoexcited triplet state of the porphyrin of ZnP(C4VAC4VB), and ZnP(C4VC4)(4) was studied by using a laser flash photolysis. In the case of ZnP(C4VAC4VB)(4), the photoexcited tripler state of the porphyrin was not quenched by the bonded viologen. On the other hand, for the ZnP(C4VC4)(4), the photoexcited triplet state of the porphyrin was quenched by the bonded viologen. (C) 1998 Elsevier Science S.A.