Flow Generation and Reaction of Diazomethane Using a Gas-Permeable Teflon Tube-in-Tube Reactor

Kappe et al. have reported a continuous generation, separation, and reactions of anhydrous diazomethane in a tube-in-tube continuous flow reactor. Diazomethane is formed in the inner tube by the treatment of N-methyl-N-nitroso-p-toluenesulfonamide with KOH, and then diffuses through the gas-permeable inner tube into the outer chamber and subsequently reacts with reactants dissolved in the solution carried within. This synthetic device is applied to methyl esterifications, cyclopropanations, [2+3] cycloadditions and Arndt-Eistert reactions. The tube-in-tube, made of gas-permeable Teflon AF-2400 (inner) and impermeable PTFE (outer), is commercially available.