The commercially available n-type semiconductive dye Violanthrone 79 was used as starting material to synthesize previously unexplored substituted violanthrenes through a reductive aromatization and functionalization strategy. By using the low-cost reducing agents zinc and sodium dithionite in combination with suitable electrophilic trapping reagents, three violanthrenes functionalized with two pivalyloxy, trimethylsiloxy, or methoxy groups were selectively obtained in high yields. Due to their octyl ether moieties, these new red dyes are highly soluble. They were characterized by means of UV/vis and fluorescence spectroscopy, and their redox properties were studied by cyclic voltammetry. The spectroscopically determined frontier molecular orbital energies are compared to those calculated by density functional theory and suggest that electron-deficient Violanthrone 79 was transformed into three electron-rich violanthrenes with molecular characteristics typically observed in molecular precursors for p-type organic semiconductors.

中文翻译：

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通过 Violanthrone 79 的还原芳构化合成不对称官能化 Violanthrenes

市售的 n 型半导体染料 Violanthrone 79 用作起始材料，通过还原芳构化和功能化策略合成以前未开发的取代紫蒽。通过将低成本的还原剂锌和连二亚硫酸钠与合适的亲电捕获剂结合使用，可以高产率地选择性地获得三个用两个新戊氧基、三甲基甲硅烷氧基或甲氧基官能化的紫蒽。由于它们的辛基醚部分，这些新的红色染料是高度可溶的。通过紫外/可见光和荧光光谱对它们进行表征，并通过循环伏安法研究它们的氧化还原特性。