In a reaction vessel fitted with a stirrer and a dropping funnel, 3.5 L of potassium carbonate solution with a mass fraction of 70% was added, and the temperature of the solution was lowered to 7 C, .
L-glutamic acid (2) 4.1 mol was added slowly, the stirring speed was controlled at 190 rpm, and two dropping funnels were used to add 4.15 mol of chloromethylstyrene solution and 80% methylenebenzene solution.
Liquid and mass fraction of 80% sodium bisulfite solution 1800ml, control the temperature of the solution is 19 , control the reaction pH is maintained at 10, all added
After continue to maintain the stirring speed of 60min, add the mass fraction of 30% oxalic acid solution to maintain the pH at 6, reduce the temperature of the solution to 3 , stand for 30h, .
Filter out the solid, mix the solid with 1100 ml of 20% potassium chloride solution, maintain the temperature of the solution at 6 , continue to stir until the solid precipitated, filtration, toluene solution was added to maintain the pH at 6 , and the solution was allowed to stand for 30h.
precipitated, extracted, toluene solvent washing, anhydrous potassium carbonate dehydration, obtained N-benzyl-L-glutamic acid 782.12g, yield 76%.
