An unexpected one-pot tandem procedure of 2-bromo-4,5-diazafluoren-9-one starting from phenanthroline with a yield of up to 50% has been described. The conversion mechanism involves three consecutive oxidation, bromination, and rearrangement reactions. A series of its hammer-shaped donor–acceptor organic semiconductors with solvent-dependent fluorescence have also been constructed via Ullman and/or Friedel–Crafts reaction. Diazafluorenes (DAFs) and derivatives are regarded as promising building blocks or candidates for donor–acceptor organic semiconductors.

中文翻译：

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通过菲咯啉及其锤状供体-受体有机半导体的串联氧化-溴化-重排反应一锅合成2-溴-4,5-二氮杂芴-9-一

已经描述了从菲咯啉开始的2-溴-4,5-二氮杂芴-9-one的一种意想不到的一锅式串联方法，产率高达50％。转化机理涉及三个连续的氧化，溴化和重排反应。还通过Ullman和/或Friedel-Crafts反应构建了一系列具有溶剂依赖型荧光的锤形供体-受体有机半导体。重氮芴（DAF）及其衍生物被认为是有前途的基石或供体-受体有机半导体的候选物。