Regioselective Oxidation of Pyrrole Derivatives with DDQ and Its Synthetic Application
作者:Ryoji Iwamoto、Yutaka Ukaji、Katsuhiko Inomata
DOI:10.1246/cl.2010.176
日期:2010.3.5
t-Butyl 4-alkyl-1H-pyrrole-2-carboxylates were oxidized with DDQ in the presence of MeOH at the α-position of the alkyl substituent at the C-4 position regioselectively to afford 4-acylpyrrole derivatives. On the other hand, treatment of the pyrroles with DDQ in the presence of AcOH furnished the corresponding 4-(1-acetoxyalkyl)pyrroles. The resulting 4-(acetoxymethyl)pyrrole reacted with various nucleophiles to afford the functionalized pyrrole derivatives in good yields.
t-丁基4-烷基-1H-吡咯-2-羧酸酯在甲醇存在下与DDQ氧化,选择性地在C-4位的烷基取代基的α位生成4-酰基吡咯衍生物。另一方面,将吡咯与DDQ和醋酸一起处理,得到相应的4-(1-乙酰氧基烷基)吡咯。所得的4-(乙酰氧基甲基)吡咯与各种亲核试剂反应,产生功能化的吡咯衍生物,产率良好。