Palladium-Catalyzed Ligand-Free ortho-Deuteration of Aromatic Carboxylic Acids with D2O

Abstract

A ligand-free, palladium-catalyzed ortho-deuteration of aromatic carboxylic acid was developed using D2O as deuterium-source. Compared to their meta-substituted analogues, an unusually lower reactivity in para- and ortho-substituted benzoic acids toward hydrogen isotope exchange was observed. Further investigation revealed that the reaction temperature is a critical parameter for the reactivity, and the modified condition can afford deuterated products with good to excellent deuterium-incorporation.

Multideuteration of Nitroaromatics by Silver-Catalyzed Hydrogen-Isotope Exchange

“…Noticeably, a similar strategy of silver-catalysis had been proven by Zhang in the selective deuteration of electro-deficient substrates such as fluoro-, bromo-, and heteroaromatics (Scheme B), whose catalytic species was elucidated by Hartwig recently . Herein, we wish to unveil our recent progress in the HIE of nitroaromatics (Scheme C), as one of our long-term goals to build up the arsenal for deuteration. , …”