Ladderization of polystyrene derivatives by palladium-catalyzed polymer direct arylation

Ladderization of polystyrene derivatives successfully proceeded by palladium-catalyzed polymer direct arylation in the presence of a phosphine ligand and pivalic acid using poly(2-bromostyrene) as a prepolymer, in which the polymer tacticity had little influence on the reaction efficiency. The reaction mechanism was supported by theoretical calculation in detail. The optical and thermal properties of pseudo-ladderized polystyrene suggested enhanced chain rigidity. Pseudo-ladderized polystyrenes could be obtained in high yield by the palladium-catalyzed polymer direct arylation using poly(2-bromostyrene) as a prepolymer.