Bottom-up modular synthesis of well-defined oligo(arylfuran)s.

Oligofurans have attracted great attention in the field of materials over the last decades because of their several advantages, such as strong fluorescence, charge delocalization, and increased solubility. Although unsubstituted or alkyl-substituted oligofurans have been well-established, there is an increasing demand for the development of the aryl decorated oligofuran with structural diversity and unrevealed properties. Here, we report the bottom-up modular construction of chemically and structurally well-defined oligo(arylfuran)s by de novo synthesis of α,β'-bifuran monomers and late-stage bromination, stannylation and subsequent coupling reaction. The preliminary study of the photophysical properties demonstrated that the polarity-sensitive fluorescence emission and high quantum yields in THF solution could be achieved by modulating the aryl groups on the oligo(arylfuran)s. These twisted molecules constitute a new class of oligofuran backbone useful for structure-activities relationship studies. Meanwhile, the experimental studies and calculations showed that tetrafurans have appropriate HOMO energy levels, and could therefore potentially be high-performance p-type semiconductors.