Dimethyl Sulfate → tert-Butyl [(2R)-1-(benzylamino)-3-methoxy-1-oxopropan-2-yl]carbamate

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 3.2 g (0.01 mol) of Intermediate 4 in 50 mL of toluene was added 0.61 g of tetrabutylammonium bromide and 5 ml of water. The resulting mixture was cooled to 10° C. and a solution of 2.4 g of sodium hydroxide in 2.5 ml of water was added dropwise maintaining the temperature below 10° C. Then, 5.54 g of dimethylsulfate was added dropwise maintaining the temperature below 10° C. After stirring at 10° C. for 2 hours, water (80 mL) was added and the reaction stirred at room temperature overnight. The layers were separated and the aqueous layer was washed twice with dichloromethane (50 mL). The combined organic phase was washed with sodium bicarbonate solution (2×30 mL) and brine. The solvent was removed under vacuum yielding 3.36 g of a pale red-oil. The oil was not purified and used directly in the following step.

Provenance & Evidence