Ethyl chloroformate → HCID 71279990, Verbindung

Temperatur

-10 °C

In a 100 mL round bottomed flask cis-3-(tertbutoxycarbonylamino)-cyclohexanecarboxylic acid (2.26 g, 9.29 mmol) was suspended in THF (15 mL). The suspension was cooled to −10° C. in an acetone-dry ice bath. To the cooled suspension was added slowly TEA (2.6 mL, 18.7 mmol) and subsequently ethyl chloroformate (1.03 mL, 10.7 mmol) so that the temperature is maintained. The cooling bath was removed upon addition and the reaction was stirred at room temperature for 3 h. The reaction mixture was cooled to −10° C. and NH4OH (2.17 mL, 55.7 mmol) was added slowly. After stirring at room temperature for 18 h, the precipitate was collected by filtration. The precipitate was washed with water and dried in vacuo at 50° C. to afford 1.67 g (74%) of (cis-3-carbamoyl-cyclohexyl)-carbamic acid tert-butyl ester as a white solid. 1H NMR (300 MHz, DMSO-d6) δ: 7.19 (br. s., 1H), 6.76 (d, J=7.9 Hz, 1H), 6.65 (br. s., 1H), 3.04-3.30 (m, 1H), 1.98-2.21 (m, 1H), 1.50-1.84 (m, 4H), 1.37 (s, 9H), 0.90-1.29 (m, 4H)

1. temperatureis maintained
2. customThe cooling bath was removed upon addition
3. temperatureThe reaction mixture was cooled to −10° C.
4. stirringAfter stirring at room temperature for 18 h
5. filtrationthe precipitate was collected by filtration
6. washThe precipitate was washed with water
7. customdried in vacuo at 50° C.

ORD-Eintrag

ord-b951d59ff023403c988dd47264bb546a

Quelldatensatz

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08658646B2