Synthesis of Imine-Bridged Planar Poly(pyridinethiophene)s. Combination of Planarization and Intramolecular Charge Transfer in Conjugated Polymers

摘要: This paper describes an approach to maximize π-conjugation in conjugated polymers by combining two complementary effects: polymer backbone planarization and intense intramolecular charge transfer (ICT). Independently, each of these methods is known promote a significant lowering the optical band gap polymers. However, as described here, combination both strategies, ICT, only has marginal effect on reducing gaps over that planarized materials possess little ICT. The studied here are planar poly(pyridinethiophene)s (PPyThs). synthesis requisite accomplished Pd-catalyzed coupling N,N'-bis(tert-butoxycarbonyl)-3,4-diamino-2,5-bis(tri-n-butylstannyl)thiophene 2,5-bis(1'-oxo)-3,6-dibromopyridines afford PPyThs then via Schiff base formation upon protic activation. exhibit enormous changes their absorption properties when iodide present solution; this dramatic change not observed with fluoride, chloride, or bromide salts, regardless cation. Therefore, have propensity optically distinguish from other halogens.