Fully conjugated push-pull dendrons with high dipole moments in excited state; synthesis and theoretical rationalization

Abstract

Novel fully conjugated push–pull dendrons were synthesized by a divergent approach to evaluate the performance of non-conventional architectures like dendritic one in charge separation processes associated with photovoltaic events. The dipole moments in excited state were estimated by the solvatochromic method, to be related to the charge separation efficiency. A 1:2 ratio of donor–acceptor groups (methoxy and nitro groups respectively) promotes the largest dipole moment in both ground and excited state (up to 17 D), due to the efficient electron density transfer over the entire molecule, through the π-electron system. The synthesized dendrons induce charge transfer on excitation as follows from UV–vis absorption–emission analysis and theoretical calculations. Copyright © 2015 John Wiley & Sons, Ltd.