Copper-catalysed low-temperature water–gas shift reaction for selective deuteration of aryl halides

The introduction of deuterium atoms into organic compounds is of importance for basic chemistry, material sciences, and the development of drugs in the pharmaceutical industry, specifically for identification and quantification of metabolites. Hence, methodologies for the synthesis of selectively labelled compounds continue to be a major area of interest for many scientists. Herein, we present a practical and stable heterogeneous copper catalyst, which permits for dehalogenative deuteration via water–gas shift reaction at comparably low temperature. This novel approach allows deuteration of diverse (hetero)aryl halides with good functional group tolerance, and no reduction of the aromatic rings or other easily reducible formyl and cyano groups. Multi-gram experiments show the potential of this method in organic synthesis and medicinal chemistry.