反应详情

To a solution of di-tert-butyl (2-hydroxy-1,3-propanediyl)biscarbamate (200 g) in methylene chloride (1.2 L) was added triethylamine (384 ml) under cooling on an ice-water bath and then a solution of methanesulfonyl chloride (64 ml) in methylene chloride (300 ml) was dropwise added at a temperature below 15° C. The mixture was stirred at the same temperature for 1.5 hours and quenched with saturated aqueous sodium hydrogencarbonate solution (200 ml). The organic layer was made acidic (pH=3) with diluted hydrochloric acid, and washed with saturated aqueous sodium hydrogencarbonate solution and brine, and dried over anhydrous magnesium sulfate. Concentration under reduced pressure gave a residue, which was triturated with ethyl acetate (100 ml)—hexane (500 ml) to give 2-[(tert-butoxycarbonyl)amino]-1-{[(tert-butoxycarbonyl)amino]methyl}ethyl methanesulfonate (202 g) as a white solid.

1. temperatureunder cooling on an ice-water bath
2. customquenched with saturated aqueous sodium hydrogencarbonate solution (200 ml)
3. washwashed with saturated aqueous sodium hydrogencarbonate solution and brine
4. dry with materialdried over anhydrous magnesium sulfate
5. concentrationConcentration under reduced pressure
6. customgave a residue, which
7. customwas triturated with ethyl acetate (100 ml)—hexane (500 ml)