Hydrochloric Acid → (Cyclopropylcarbamoyl)formic acid

Temperature

0 °C

Ethyl chloro(oxo)acetate (96 mL, 0.86 mol) was added over 10 minutes to a −20° C. solution of cyclopropylamine (60 mL, 0.86 mol) and pyridine (70 mL, 0.86 mol) in dichloromethane (740 mL), and the reaction mixture was stirred at 0° C. for 1 hour, then at 20° C. for 20 hours. The reaction mixture was washed with aqueous hydrochloric acid (1 M, 3×185 mL), then the organic layer was stirred with aqueous sodium hydroxide solution (1 M, 930 mL, 0.93 mol) for 30 minutes. The resulting aqueous layer was acidified to pH 1 with concentrated hydrochloric acid (78 mL), treated with sodium chloride (100 g), and extracted with dichloromethane (6×500 mL) and ethyl acetate (6×500 mL). The combined organic layers were dried over magnesium sulfate, filtered, and concentrated in vacuo; the resulting solid was mixed with ethyl acetate (150 mL) and warmed to reflux. After cooling to room temperature over 16 hours with stirring, the solid was collected via filtration and washed with ethyl acetate, affording the product as a sparkling white solid. Yield: 67.8 g, 0.525 mol, 61%. LCMS m/z 130.0 [M+H]+. 1H NMR (400 MHz, DMSO-d6) δ 13.73 (br s, 1H), 8.83 (br d, J=4.0 Hz, 1H), 2.68-2.77 (m, 1H), 0.61-0.68 (m, 2H), 0.54-0.61 (m, 2H).

1. waitat 20° C. for 20 hours
2. washThe reaction mixture was washed with aqueous hydrochloric acid (1 M, 3×185 mL)
3. extractionextracted with dichloromethane (6×500 mL) and ethyl acetate (6×500 mL)
4. dry with materialThe combined organic layers were dried over magnesium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. additionthe resulting solid was mixed with ethyl acetate (150 mL)
8. temperaturewarmed to reflux
9. temperatureAfter cooling to room temperature over 16 hours
10. stirringwith stirring
11. filtrationthe solid was collected via filtration
12. washwashed with ethyl acetate

ORD record

ord-4cbd04966ae6496998069c3248b60f84

Source dataset

uspto-grants-2015_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09120788B2