The use of esters as blocking groups at the C2 position on a range of 3-substituted 5-membered ring heteroaromatics such as thiophenes or furans, allows control of the regioselectivity for the palladium-catalysed direct arylation at C5-H. This arylation can be followed by easy decarboxylation. This method allows sequential catalytic C5 arylation, decarboxylation and catalytic C2 arylation reactions.
在一系列三取代五元环杂芳族化合物(如
噻吩或
呋喃)的 C2 位使用
酯作为封端基团,可以控制
钯催化的 C5-H 直接芳基化反应的区域选择性。这种芳基化反应之后可以进行简单的
脱羧反应。这种方法可以连续催化 C5 芳基化、
脱羧和催化 C2 芳基化反应。