Four novel diketopyrrolopyrrole (DPP) derivatives have been synthesized and characterized: the dyes are based on a DPP electron acceptor core symmetrically functionalized with donor bi-furyl moieties and end capped with four different auxiliary electron-acceptor groups. Because of the alternation along the molecular backbone of electron acceptor and donor groups, all the dyes are characterized by optical absorption maxima approaching or exceeding 700 nm. In the solid state, this optical behavior determines for all the dyes a very low optical bandgap ranging from 1.57 eV to 1.29 eV, while electrochemical characterization shows a clear dependence of the LUMO energies on the strength of the auxiliary electron-acceptor groups. All the dyes are characterized by stable LUMO energies suitable for their application as n-type semiconductors. Organic field-effect transistors based on the reported compounds display actually n-type behavior and, in three cases, a very interesting and balanced ambipolar charge transport behavior was moreover observed.

已合成并表征了四种新颖的二酮吡咯并吡咯（DPP）衍生物：染料基于以供体双呋喃基部分对称功能化并以四个不同的辅助电子受体基团封端的DPP电子受体核。由于沿着电子受体和供体基团的分子主链交替，所有染料的特征在于最大吸光度接近或超过700 nm。在固态状态下，这种光学行为决定了所有染料的极低光学带隙，范围为1.57 eV至1.29 eV，而电化学表征显示LUMO能量对辅助电子受体基团的强度有明显的依赖性。所有染料均具有稳定的LUMO能量，适合用作n型半导体。