反应详情

温度

0 °C

The solution of dimethyl 3-(2-hydroxyethylamino)-2-pentenedioate was cooled to 0° C., and triethylamine (235 mL, 170.6 g, 1.69 mol) was added in one portion. Methanesulfonyl chloride (168.8 g, 1.47 mol) was added dropwise via an addition funnel over 3.75 hours, with the temperature rising to 5°-7° C. The medium-yellow slurry darkened to yellow-orange as the last 10 mL methanesulfonyl chloride was added. The mixture was stirred at 0° C. for an additional 2 hours, and water (250 mL) added. The organic phase was washed with water (4×500 mL) and brine (250 mL), and dried overnight over anhydrous magnesium sulfate. After filtration, the solvents were evaporated on a rotary evaporator under reduced pressure at 50° C. to afford 310.0 g (93% yield) of dimethyl 3-(2-methanesulfonylethylamino)-2-pentenedioate as a red oil. The mesylenamine may be purified at this point, if necessary or desired, and may be converted to the haloenamine by the following method or used directly in Step 2, Alternate II.

1. customrising to 5°-7° C
2. additionwas added
3. washThe organic phase was washed with water (4×500 mL) and brine (250 mL)
4. dry with materialdried overnight over anhydrous magnesium sulfate
5. filtrationAfter filtration
6. customthe solvents were evaporated on a rotary evaporator under reduced pressure at 50° C.