Continuous-flow catalytic deuterodehalogenation carried out in propylene carbonate

• Published in: Green chemistry : an international journal and green chemistry resource : GC Vol. 21; no. 5; pp. 956 - 961
• Main Authors: Orsy, György, Fülöp, Ferenc, Mándity, István M
• Format: Journal Article
• Language: English
• Published: CAMBRIDGE Royal Soc Chemistry 2019; Royal Society of Chemistry
• Subjects: Activated carbon; Amides; Bromine; Catalysts; Catalytic converters; Chemistry; Chemistry, Multidisciplinary; Chlorine; Deuteration; Deuterium; Fluorine; Green & Sustainable Science & Technology; Green chemistry; Iodine; NMR; Nuclear magnetic resonance; Optimization; Palladium; Physical Sciences; Propylene; Science & Technology; Science & Technology - Other Topics; Substitutes; SELECTIVE DEUTERATION; DEUTETRABENAZINE; HYDROGENATION; PROTECTING GROUP; CHEMISTRY; SPHERICAL ACTIVATED CARBONS; AEROBIC OXIDATION; PARTICLE-SIZE; BATCH; DEUTERIUM
• ISSN: 1463-9262; 1463-9270
• DOI: 10.1039/c8gc03192d

A selective continuous-flow (CF) deuterodehalogenation approach is described performed in propylene carbonate, which is considered as one of the greenest solvents. Various CF technologies are known for hydrodehalogenation reactions; however, they are not directly transferable for deuteration transformations. A novel spherical activated carbon-supported palladium catalyst has been found to be useful for the catalytic deuterodehalogenation of haloarenes. After careful reaction parameter optimization, complete conversion was achieved for bromine- and chlorine-substituted haloarenes. Nonetheless, no deuterium exchange was observed for the fluorine substituent, while iodine-substituted compounds poisoned the catalyst. Importantly, deuterated compounds were obtained with a rate of 3 mg min −1 and the catalyst showed reasonable reusability. Moreover, benzylic amides were also deuterated without any debenzylation side-reaction. Continuous-flow dehalodeuteration of aromatics carried out in propylene carbonate for a liveable future.