A facile synthesis of dithieno[3,2-b:6,7-b]fluorenes via a tandem annulation–reduction
作者:Xiaoli Xiong、Qiancai Liu、Jun Zhang、Min Zhu、Yanmei Wang、Shiming Deng
DOI:10.1039/c3ra41927d
日期:——
A concise and facile synthesis of 2,8-disubstituted dithieno[3,2-b:6,7-b]fluorenes starting from 2,7-dihydroxyfluorenone is reported. The key step involved is the tandem annulationâreduction of a 3,6-dichloro-2,7-di(alkynyl)fluorenone using Na2S·9H2O as a sulfur surrogate and reductant. The final dithiophene-fused fluorenes are obtained in reasonable yields (23â43%).
报道了一种从2,7-二羟基芴酮出发合成2,8-二取代二噻吩并[3,2-b:6,7-b]芴的简便方法。该方法的关键步骤是利用Na2S·9H2O作为硫源和还原剂,对3,6-二氯-2,7-二(炔基)芴酮进行串联环化还原反应。最终所得的二噻吩并芴产率合理(23%~43%)。