An efficient catalytic system for the hydrogenation of quinolines

A new catalytic system ([Ru(p-cymene)Cl2]2/I2) has been developed for the hydrogenation of quinoline derivatives with high reactivity. For the 2-methyl-quinoline, the hydrogenation reaction can proceed smoothly at an S/C of 20,000/1 with complete conversion. The iodine additive is important for the reactivity.