Novel SO3H-functionalized ionic liquids catalyzed a simple, green and efficient procedure for Fischer indole synthesis in water under microwave irradiation
作者:Bai Lin Li、Dan-Qian Xu、Ai Guo Zhong
DOI:10.1016/j.jfluchem.2012.09.010
日期:2012.12
ionic liquids were successfully applied as catalysts for one-pot Fischer indole synthesisundermicrowaveirradiation and in a water medium. Various types of indoles were prepared using single-carbonyl ketones/aldehydes or cyclohexandiones with aryhydrazine hydrochlorides in 86–96% yields in waterundermicrowaveirradiation. The indole products could be conveniently separated from the reaction mixture
新型SO 3 H官能化离子液体已成功地用作微波辐射下和在水介质中一锅费休吲哚合成的催化剂。在微波辐射下,使用单羰基酮/醛或环己二酮与盐酸肼肼制备的各种类型的吲哚,在水中的产率为86-96%。吲哚产物可通过过滤方便地从反应混合物中分离出来,并且[(HSO 3 -p)2 im] [CF 3 SO 3 ] / H 2 O的催化体系可直接重复使用而无需任何处理。整个过程简单,省时且环保。
Fischer indole synthesis catalyzed by novel SO3H-functionalized ionic liquids in water
the one-pot Fischerindole synthesis in water medium. The sequence of the catalytic activity observed in the transformation was in good agreement with the Brønsted acidity order determined by the Hammett method. Various types of indoles from single-carbonyl ketones/aldehydes and cyclohexandiones were provided in 68–96% yields using the catalytic system of [(HSO3-p)2im][HSO4]/H2O. The indole products could
We describe iron‐catalyzed oxidativecouplingcyclization of tetrahydrocarbazoles or THβCs or THγCs to form benzofuroindolenines as fused polycyclic indoles. This mild, efficient and simple approach afforded a library of more than 52 complex compounds across a range of substrate classes with good to excellent yields.
the efficient construction of three-dimensional bisindolines via oxidative coupling cyclization in an intermolecular manner. This reaction is featured by its operational simplicity, metal-free conditions, lack of protecting group, and high selectivity. Notably, a wide range of anilines are suitable in this intermolecular cyclization, furnishing corresponding bisindolines in up to 98% yield.