Carbon Dioxide → 4-Cyclopropoxybenzoic acid

Temperatur

-78 °C

To a −78° C. solution of 1-bromo-4-(cyclopropoxy)benzene (33 g, 154.9 mmol) in tetrahydrofuran (500 mL) add 1.6 M butyl lithium in hexane (96.8 mL, 154.9 mmol) while maintaining a temperature below −70° C. Stir the mixture at −78° C. for 20 minutes after the addition. Add dry ice (464.6 mmol) in 3 portions 5 minutes apart. Stir the mixture at −78° C. for 30 minutes. Remove the cooling bath and quench the mixture with 10% sodium hydrogen sulfate (NaHSO4) (200 mL). Warm the mixture to ambient temperature and extract 3× with EtOAc (300 mL). Combine the organics and wash once with brine, dry over sodium sulfate, filter, and concentrate under reduced pressure. Suspend the residue in diethyl ether and filter. Dry the solid in a vacuum oven to give the title compound (12.9 g, 47%): MS (m/z): 179 (M+1).

1. temperaturewhile maintaining a temperature below −70° C
2. additionafter the addition
3. customin 3 portions 5 minutes
4. stirringStir the mixture at −78° C. for 30 minutes
5. customRemove the cooling bath
6. customquench the mixture with 10% sodium hydrogen sulfate (NaHSO4) (200 mL)
7. temperatureWarm the mixture to ambient temperature
8. extractionextract 3× with EtOAc (300 mL)
9. washCombine the organics and wash once with brine
10. dry with materialdry over sodium sulfate
11. filtrationfilter
12. concentrationconcentrate under reduced pressure
13. filtrationfilter
14. customDry the solid in a vacuum oven

ORD-Eintrag

ord-7313c14a41944c09964968d8185c370e

Quelldatensatz

uspto-grants-2012_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08299061B2