Regioselective Oxidative Coupling Reactions of 3-Substituted Thiophenes with Arylboronic Acids
作者:Ingo Schnapperelle、Stefan Breitenlechner、Thorsten Bach
DOI:10.1021/ol201292v
日期:2011.7.15
Under optimized conditions, 3-substituted thiophenes (EWG = COOEt, PO(OEt)2) undergo a facile and regioselective oxidative coupling reaction at carbon atom C4. The reactions were performed with various aryl boronic acids as nucleophiles in the presence of silver oxide (2.0 equiv), cesium trifluoroacetate (tfa) (1.0 equiv), benzoquinone (BQ) (0.5 equiv), and catalytic amounts of Pd(tfa)2 (10 mol %)
在优化的条件下,3-取代的噻吩(EWG = COOEt,PO(OEt)2)在碳原子C4处进行便捷的区域选择性氧化偶联反应。反应是在氧化银(2.0当量),三氟乙酸铯(tfa)(1.0当量),苯醌(BQ)(0.5当量)和催化量的Pd(tfa)2存在下,以各种芳基硼酸作为亲核试剂进行的。使用三氟乙酸(TFA)作为溶剂的(10mol%)。