Hydrogen–Deuterium Exchange Reactions of Aromatic Compounds and Heterocycles by NaBD₄‐Activated Rhodium, Platinum and Palladium Catalysts

Abstract

Conventional thermal and microwave conditions were compared for hydrogen-deuterium (H/D) exchange reactions of aminobenzoic acids catalysed by NaBD(4)-activated Pd/C or RhCl(3) with D(2)O as the deuterium source. We also investigated different NaBD(4)-activated metal catalysts (including Pd/C, RhCl(3) and Pt/C) under microwave conditions for an efficient H/D exchange of aromatic and heterocyclic compounds. Even higher deuterium incorporations were obtained for Pd/C and Pt/C catalyst mixtures due to the previously observed synergistic effect. Finally, we have applied these optimised conditions for one-step syntheses of the MS standards of several pharmaceutically active compounds.