Multifunctional properties of monodisperse end-functionalized oligophenylenevinylenes*

Abstract: Novel series of monodisperse, end-functionalized oligophenylenevinylenes (OPVs) containing up to eight phenyl rings have been designed and synthesized by a convergent ap-proach using the stereoselective Wadsworth–Emmons reactions for an investigation of tech-nologically useful functional properties. According to PM3 semiempirical quantum mechan-ical calculations, the frontier molecular orbitals and the energy gap of an OPV could be shifted or tuned by the functional substituent(s) that are incorporated as end-caps. Our theo-retical and experimental evidences have shown that the end-substituents of an oligomer do not affect coplanarity of the π-conjugated system. It has also been found that the newly syn-thesized OPVs can exhibit various useful functional properties such as light-emitting prop-erties, photovoltaic effects, third-order nonlinear optical responses, and chemical sensing properties depending on the nature of the end-substituents. In this contribution, the structural factor(s) that can enhance a specific functional property of a molecule or material will be dis-cussed. Poly(phenylenevinylene) (PPV) and its derivatives have been extensively explored and investigated for various technologically useful functional properties in the past two decades because of their potentia