VISIBLE-LIGHT INDUCED PHOTOCATALYSIS OF PARTIALLY FLUORINATED POLY(P-PHENYLENE) AND RELATED LINEAR PHENYLENE DERIVATIVES

As a partially fluorinated poly(p-phenylene) derivative, yellow powder PF-PPP-n with high solubility in organic solvents was prepared as a mixture of oligomers by nickel-catalyzed polycondensation of the Grignard reagent from 1-bromo-2,4,6-trifluorobenzene. PF-PPP-n shows photocatalytic activity for reduction of water to H2, carbonyl compounds to alcohols, and dimethyl maleate and fumarate to the succinate under visible-light (lambda>400 nm) irradiation in the presence of triethylamine as a sacrificial electron donor. The photocatalysis was compared with those of other related fluorinated linear aromatics such as perfluorinated poly(p-phenylene sulfide) (F-PPS-n), perfluorinated poly(p-phenylene) (F-PPP-n). Their spectral characteristics and photocatalysis are discussed on the basis of the semiempirical molecular orbital calculations.