Proton/deuterium exchange in cinchonidine and deuteration of ethyl pyruvate using platinum/Al2O3 catalysts

A study of deuteration of cinchonidine (CD) under conditions (pressure (40 bar), temperature (25°C) and reaction times (2 h)) used for usual hydrogenation of ethyl pyruvate showed that the vinyl group is totally transformed into an ethyl (deuterated) and that H for D exchanges occur on the quinoline ring and at C9. Deuteration of ethyl pyruvate under the same conditions showed that no deuteration occurs at the chain-methyl, neither in toluene nor in AcOH, indicating that the enol is not the reacting species.