AbstractTripodal donor‐acceptor (D‐A) small molecules Tr‐Np3 and Tr‐T‐Np3 consisting of triphenyl triazine and 1,8‐naphthalimide, without and with a thiophene spacer have been synthesized. Their optical and redox properties were thoroughly investigated along with their utilization as photocatalysts in organic transformations. Compounds Tr‐Np3 and Tr‐T‐Np3 showed broad absorption in the range of 290–480 nm in solutions and 300–510 nm in thin films. These tripodal molecules displayed wide optical bandgaps of (Egopt) 3.10 eV and 2.64 eV with very deep‐lying HOMO energy levels (−6.60 eV and −6.03 eV) and low‐lying LUMO levels (−3.50 eV and −3.40 eV). Appreciable electron mobilities of 5.24×10−4 cm2/Vs and 6.14×10−4 cm2/Vs were obtained for compounds Tr‐Np3 and Tr‐T‐Np3 respectively by space‐charge limited current (SCLC) measurements. Metal‐free tripodal molecules Tr‐Np3 and Tr‐T‐Np3 showed excellent photocatalytic abilities towards condensation of aromatic aldehydes and o‐phenylenediamine followed by cyclization under visible light to yield benzimidazole derivatives that are of high medicinal value.
摘要 合成了由三苯基三嗪和 1,8-萘二甲酰亚胺组成的三足供体-受体(D-A)小分子 Tr-Np3 和 Tr-T-Np3,其中不含噻吩间隔物,也含噻吩间隔物。我们深入研究了它们的光学和氧化还原特性,以及它们在有机转化过程中作为光催化剂的用途。Tr-Np3 和 Tr-T-Np3 化合物在溶液中的吸收范围为 290-480 纳米,在薄膜中的吸收范围为 300-510 纳米。这些三元分子的光带隙分别为 (Egopt) 3.10 eV 和 2.64 eV,具有很深的 HOMO 能级(-6.60 eV 和 -6.03 eV)和很低的 LUMO 能级(-3.50 eV 和 -3.40 eV)。通过空间电荷限流(SCLC)测量,化合物 Tr-Np3 和 Tr-T-Np3 的电子迁移率分别为 5.24×10-4 cm2/Vs 和 6.14×10-4 cm2/Vs。在可见光下,无金属三元分子 Tr-Np3 和 Tr-T-Np3 对芳香醛和邻苯二胺的缩合以及环化反应表现出了极佳的光催化能力,从而生成了具有极高药用价值的苯并咪唑衍生物。