Tate 10 mmol of reactant, 4 g of mo

Tate 10 mmol of reactant, 4 g of molecular sieves and 20 mL of methyl tert-butyl ether in a 50 mL round bottom flask fitted with a septum and cool to 25 °C.Add 30 mmol of sulfuric acid to this solution very slowly using syringe.Carry out the reaction at 25 °C for 2h.Quench the reaction slowly into 25 mL of saturated aqueous solution of sodium bicarbonate.Separate the organic layer and extract the aqueous layer twice with hexane.Wash the combined organic layer with water.Dry the combined organic layer over sodium sulphate.Remove the solvent by distilation to obtain (S)-di-tert-butyl 2-aminosuccinate.