Palladium-catalysed direct 3- or 4-arylation of thiophene derivatives using aryl bromides
作者:Jia Jia Dong、Julien Roger、Henri Doucet
DOI:10.1016/j.tetlet.2009.03.155
日期:2009.6
The palladium-catalysed direct 3- or 4-arylation of 2,5-disubstituted thiophenes using aryl bromides gives a simple access to a variety of 3- or 4-arylthiophene derivatives. Moderate to good yields of 3-arylated thiophenes were obtained using 2,5-dimethylthiophene. In the presence of unsymmetrically disubstituted, 2-acetyl-5-methylthiophene, a regioselective arylation on carbon 4 of thiophene was observed
使用芳基溴化物,钯催化的2,5-二取代噻吩的3-或4-芳基直接芳构化,可轻松获得各种3-或4-芳基噻吩衍生物。使用2,5-二甲基噻吩获得了中等至良好产率的3-芳基噻吩。在不对称双取代的2-乙酰基-5-甲基噻吩的存在下,观察到噻吩的碳4上的区域选择性芳基化。该反应仅提供与碱缔合的HX作为副产物,并减少了制备这些化合物的步骤数。