A cross-linked conjugated metallopolymer comprised of bisaxially coordinated ruthenium tetra-t-butyl phthalocyanine connected by quaterthiophene linkers

A ruthenium tetra-t-butylphthalocyanine bisaxially ligated with 3,5-bis(2,2′-bithiophene-5-yl)pyridine was synthesized from ruthenium tetra-t-butylphthalocyanine dimer. The complex was electropolymerized (in CH2Cl2 and CH3CN, with and without addition of BF3·Et2O) to yield an insoluble conjugated metallopolymer, which was characterized by cyclic voltammetry and UV–vis spectroelectrochemistry. The polymer combines the electrochemical and spectral properties of the phthalocyanine and of a polythiophene-type conjugated polymer. In the presence of BF3, the polymer can be reversibly p-doped and de-doped. Materials obtained in CH2Cl2 (tested in the same solvent) and in CH3CN/BF3 (tested in CH3CN) exhibit an unusual hysteresis of redox properties.

► Ruthenium tetra-t-butylphthalocyanine bisaxially ligated with a bis-bithiophenyl pyridine ligand electropolymerized in various media to form a conjugated metallopolymer
► High redox stability in CH2Cl2, CH2Cl2/BF3·Et2O, good stability in CH3CN/BF3·Et2O; cyclic voltammogram exhibits both oligothiophene and phthalocyanine features
► Wide UV–vis absorption (to ca. 900 nm in the presence of BF3 and to ca. 700 nm without BF3)
► Materials obtained in CH2Cl2 (tested in the same solvent) and in CH3CN/BF3 (tested in CH3CN) exhibit an unusual hysteresis of redox properties, possibly caused by redox matching of singly oxidized phthalocyanine and the pyrydine–quaterthiophene copolymer.