Catalytic Deuteration of Aldehydes with D2O

A procedure is presented that enables the direct deuteration of the formyl C–H bond of aldehydes using D 2 O as the deuterium source and commercially available RuHCl(CO)(PPh 3 ) 3 as the catalyst. Up to 84% deuterium incorporation can be achieved in a single experiment. Multiple iterations can be carried out to further increase the deuteration.