Deuteration of Pd-activated C(sp(2))-H bonds in the solid state

We report mechanochemically-induced deuteration of Pd-activated aromatic C(sp(2))-H bonds at ambient temperature under solvent-free conditions. Deuterium was sourced from cysteine-d(4) to obtain mono- or dideuterated products from various aromatic palladacycles. Next to good deuteration yields, based on time-resolved in situ Raman monitoring and DFT calculations, we present a detailed view of the reaction course in the solid state. The obtained knowledge could lead to the broader application of this methodology for the deuteration of organics.

Automated summary

We report the mechanochemically-induced deuteration of aromatic C(sp(2))-H bonds activated by Pd at ambient temperature without the need for solvents. Deuterium was sourced from cysteine-d(4) to obtain mono- or dideuterated products from different aromatic palladacycles. Besides the high deuteration yields, we provide a detailed view of the reaction course in the solid state through time-resolved in situ Raman monitoring and DFT calculations. The obtained knowledge could lead to the broader application of this methodology for the deuteration of organic compounds.