109-83-1

4316-73-8

General procedure for the synthesis of sodium N-methylglycinate from N-methyl-2-hydroxyethylamine: 10 g of Cu/Ni based Nguyenne catalyst (Degussa AG, BOO 111, on a dry matter basis) was placed as an aqueous suspension in a 600 ml autoclave, which was equipped with a stirrer, a pressure control valve, and a jacketed heating unit. Subsequently 75 g of N-methyl-2-hydroxyethylamine and 204 g of 20 wt% sodium hydroxide solution were added. After sealing the autoclave, the reaction mixture was warmed up to 160°C by jacket heating. During this process, the pressure of the hydrogen gas produced was gradually increased and the system pressure was maintained at 10 bar (absolute pressure) by adjusting the opening of the pressure control valve. After 4 hours of reaction, gas release was completely stopped and the reactor was cooled to 90°C. After stopping stirring, the catalyst precipitated within 1 h. A portion of the supernatant with sodium N-methylglycinate solution was removed from the autoclave via piping. The catalyst was retained in the reactor and could be reused for the next batch of reaction. For each subsequent cycle, the catalyst suspension remaining in the reactor is mixed with specified amounts of N-methyl-2-hydroxyethylamine and sodium hydroxide solution and the reaction is initiated by heating. In addition to the initial batch, 270 g of colorless sodium N-methylglycinate solution was obtained for each cycle at a concentration of 40.0 wt% (equivalent to 97.2% of the theoretical yield).