Chiral phosphoric acid catalyzed enantioselective transfer deuteration of ketimines by use of benzothiazoline as a deuterium donor: synthesis of optically active deuterated amines

By use of 2-deuterated benzothiazoline as a deuterium donor in combination with a chiral phosphoric acid, the transfer deuteration of ketimine and α-iminoester took place smoothly to give α-deuterated amines in high yields with excellent enantioselectivities. The remarkable kinetic isotope effect suggests that carbon-deuterium bond cleavage is the rate-determining step.