Regiodivergent DH or HD Addition to Alkenes: Deuterohydrogenation versus Hydrodeuterogenation.

The regioselective and regiodivergent addition of H-D to a variety of 1,1-diarylalkenes was realized utilizing selectively deuterated dihydroaromatic compounds, which were generated by cobalt catalysis. The reaction was initiated by catalytic amounts of BF3·Et2O by abstracting hydride or deuteride ions from the respective dihydroaromatic reducing agents and led to a highly regioselective incorporation of deuterium and hydrogen at the desired positions of the starting material.