Effective Palladium-Catalyzed Hydroxycarbonylation of Aryl Halides with Substoichiometric Carbon Monoxide

A protocol for the Pd-catalyzed hydroxy­carbonylation of aryl iodides, bromides, and chlorides has been developed using only 1–5 mol % of CO, corresponding to a <i>p</i>_CO as low as 0.1 bar. Potassium formate is the only stoichiometric reagent, acting as a mildly basic nucleophile and a reservoir of CO. The substoichiometric CO could be delivered to the reaction from an acyl-Pd­(II) precatalyst, which provides both the CO and an active catalyst, and thereby obviates the need for handling a toxic gas

Silacarboxylic Acids as Efficient Carbon Monoxide Releasing Molecules: Synthesis and Application in Palladium-Catalyzed Carbonylation Reactions

Silacarboxylic acids have been demonstrated to be easy to handle, air-stable carbon monoxide precursors. Different silacarboxylic acids were synthesized from the corresponding chlorosilanes and carbon dioxide, and their decarbonylation, upon treatment with an array of activators, was evaluated. The release of CO from crystalline MePh₂SiCO₂H proved to be highly efficient, and it was successfully applied in a selection of palladium-catalyzed carbonylative couplings using near-stoichiometric quantities of carbon monoxide precursor. Finally, the synthesis of MePh₂Si¹³CO₂H and its application in carbonyl labeling of two bioactive compounds was demonstrated

Two-Chamber Hydrogen Generation and Application: Access to Pressurized Deuterium Gas

Hydrogen and deuterium gas were produced and directly applied in a two-chamber system. These gaseous reagents were generated by the simple reaction of metallic zinc with HCl in water for H₂ and DCl in deuterated water for D₂. The setup proved efficient in classical Pd-catalyzed reductions of ketones, alkynes, alkenes, etc. in near-quantitative yields. The method was extended to the synthesis and isotope labeling of quinoline and 1,2,3,4-tetra­hydro­quinoline derivatives. Finally, CX-546 and Olaparib underwent efficient Ir-catalyzed hydrogen isotope exchange reactions

Alexander Garden to John Ellis

Alexander Garden to John Elli