A robust transition-metal-free strategy is presented to access novel β-carboline-tethered benzothiophenone derivatives from 1(3)-formyl-β-carbolines using elemental sulfur activated by Et3N/DMSO. This expeditious catalyst-free reaction proceeds through the formation of β-carboline-based 2-nitrochalcones followed by an incorporation of sulfur to generate multifunctional β-carboline-linked benzothiophenones in good to excellent yields. The synthetic strategy could also be extended towards the synthesis of β-carboline-linked benzothiophenes. Moreover, the afforded products emerged as promising fluorophores and displayed excellent light-emitting properties with quantum yields (ΦF) up to 47%.
本文提出了一种稳健的无过渡金属策略,利用元素硫在 Et3N/DMSO 的活化作用下,从 1(3)-formyl-β-carbolines 中获得新型 β-carboline拴系苯并噻吩酮衍生物。这种快速的无催化剂反应通过形成以 β-咔啉为基础的 2-硝基查耳酮,然后掺入硫元素,生成多功能的 β-咔啉连接的苯并噻吩酮,收率良好甚至极佳。该合成策略还可扩展用于合成 β-咔啉连接的苯并噻吩。此外,所得到的产物作为有前途的荧光体,显示出优异的发光特性,量子产率(ΦF)高达 47%。