MIL-101(Cr)-SO3H Catalyzed Transfer Hydrogenation of 2-Substituted Quinoline Derivatives

The 2-substituted-1,2,3,4-tetrahvdroquinoline skeletons are widely found in natural products and have shown antimalarial, antioxidant as well as other biological activities. In this work, MIL-101(Cr)-SO3 H is an efficient heterogeneous catalyst for the transfer hydrogenation of a series of 2-substituted quinoline derivatives with Hantzsch ester as the hydrogen source. This protocol operates under mild conditions, tolerates a wide range of 2-substituted quinoline derivatives, and the catalyst could be recovered and reused four times without considerable loss of catalytic activities, which provides a new catalytic system for the construction of 2-substituted-1,2,3,4-tetrahvdroquinoline derivatives.