Palladium-Catalysed Direct Heteroarylations of Heteroaromatics Using Esters as Blocking Groups at C2 of Bromofuran and Bromothiophene Derivatives: A One-Step Access to Biheteroaryls
作者:Henri Doucet、Hai Fu、Liqin Zhao、Christian Bruneau
DOI:10.1055/s-0031-1290453
日期:2012.9
the palladium-catalysed direct arylation of heteroaromatics. As their C5 is blocked by ester groups, the use of these substrates prevents the formation of dimers or oligomers, and therefore allows the formation of biheteroaryls in high yields. A very wide variety of heteroaromatics can be coupled with these two reagents. Moreover, with methyl 5-bromo-2-furoate, sequential catalytic C5 arylation, decarboxylation
已发现 5-溴-2-糠酸甲酯和 5-溴噻吩-2-羧酸乙酯是 2-卤代呋喃和 2-卤代噻吩的有用替代试剂,可用于钯催化的杂芳烃直接芳基化。由于它们的 C5 被酯基团封闭,因此使用这些底物可以防止二聚体或低聚物的形成,因此可以高产率地形成二杂芳基。种类繁多的杂芳烃可以与这两种试剂偶联。此外,使用 5-溴-2-糠酸甲酯,连续催化 C5 芳基化、脱羧、催化 C2-芳基化反应允许合成 2,5-二芳基化呋喃衍生物。