Synthesis of Quinoline-2-thiones by Selective Deoxygenative C - H/C - S Functionalization of Quinoline N -Oxides with Thiourea.

Quinoline-2-thiones valuable for synthetic and medicinal chemistry applications were obtained with excellent regioselectivity employing a deoxygenative C-H functionalization of readily available quinoline- N -oxides with thiourea upon activation with triflic anhydride. Unlike the current methods, this approach provides general access to diverse quinoline-2-thiones functionalized with groups of different electronic natures. Experimental simplicity and good to high yields are advantages of this protocol. Given the high reactivity of quinoline-2-thiones, this method provides an entry point for the synthesis of diverse organosulfur quinoline scaffolds.