An efficient chemoselective reduction of isatin derivatives using catalyst B(C6F5)3, benzyldimethylsilane, and H2O is described. Notably, a small amount of water is shown to be a highly effective reaction promoter that decreases the reaction time and temperature for the synthesis of indolin-3-ones. Moreover, using method, excellent deuterium incorporation is achieved via the catalytic α-deuteration of indolin-3-ones using B(C6F5)3 and D2O.