Carbon Dioxide → 2-Chloro-6-(trifluoromethyl)quinoline-3-carboxylic acid

Temperature

-78 °C

A solution of 1.54 ml (11.0 mmol) diisopropylamine in THF (38 ml) was cooled to 0° C. 6.9 ml (1.6 M in hexane, 11.0 mmol) n-BuLi were added dropwise at this temperature and then the mixture was stirred for 30 min at −78° C. Then a solution of 2.31 g (10.0 mmol) 2-chloro-6-(trifluoromethyl)quinoline in THF (12 ml) was added dropwise at −78° C. and the mixture was stirred for a further 30 min at −78° C. Then the reaction solution was poured onto finely dispersed dry ice. After heating to RT the mixture was concentrated to small volume under vacuum and the residue was taken up with water. It was made alkaline with a 1N aqueous NaOH solution and then washed with ether. Then it was acidified with a 10% aqueous hydrochloric acid and extracted with EE. The organic phase was washed with water and brine, dried over Na2SO4, filtered and concentrated to small volume under vacuum. 198 mg (0.7 mmol, 72%) 2-chloro-6-(trifluoromethyl)quinoline-3-carboxylic acid were obtained as residue.

1. stirringthe mixture was stirred for a further 30 min at −78° C
2. temperatureAfter heating to RT the mixture
3. concentrationwas concentrated to small volume under vacuum
4. washwashed with ether
5. extractionextracted with EE
6. washThe organic phase was washed with water and brine
7. dry with materialdried over Na2SO4
8. filtrationfiltered
9. concentrationconcentrated to small volume under vacuum

ORD record

ord-bf1c00c672c24f5db3bcc063904c8554

Source dataset

uspto-grants-2013_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08399673B2