Regioselective Stille coupling reactions of 3,5-dibromo-2-pyrone with various aryl and vinyl stannanes
作者:Won-Suk Kim、Hyung-Jin Kim、Cheon-Gyu Cho
DOI:10.1016/s0040-4039(02)02305-5
日期:2002.12
regioselective Stille coupling reactions with aryl, heteroaryl and vinyl stannanes to produce various 3-substituted, 5-bromo-2-pyrones. Addition of a catalytic amount of CuI greatly increased the selectivity and chemical yield of the desired 3-aryl-5-bromo-2-pyrone. Second Stille coupling reactions on the resulting 3-aryl-2-pyrones gave rise to a series of potentially useful 2-pyrones with two different functionalities
3,5-二溴-2-吡喃酮与芳基,杂芳基和乙烯基锡烷进行容易的区域选择性Stille偶联反应,产生各种3-取代的5-溴-2-吡喃酮。加入催化量的CuI极大地提高了所需的3-芳基-5-溴-2-吡喃酮的选择性和化学收率。在所得的3-芳基-2-吡喃酮上进行的第二Stille偶联反应产生了一系列潜在有用的2-吡喃酮,其在C3和C5位置具有两个不同的官能度,分离产率高至优异。在C3位带有吡啶基的2-Pyrones可以与苄基乙烯基醚发生路易斯酸催化的Diels–Alder环加成反应。