反应详情

nBuLi (2.2M in hexanes; 7.50 ml, 16.49 mmol) was added dropwise over 2 min to a solution of 8-bromo-2-chloroquinoline (4.00 g, 16.49 mmol, Biofine International, Inc., Vancouver, BC) in THF (82 ml) at −78° C. The resulting mixture was stirred at −78° C. for 20 min before CO2 was bubbled into the solution for 5 min at −78° C. The mixture was quenched with 2 N HCl (10 ml). The resulting mixture was partitioned between 100 ml of Et2O and 1 N NaOH. The organic layer was separated, and the aq. layer was acidified to ˜pH 2 with 5 N HCl and extracted 3 times with 150 ml Et2O. The combined organic extracts were dried over Na2SO4 and concentrated to provide 2-chloroquinoline-8-carboxylic acid (181a, >99% yield) as a light brown solid. MS (ESI, pos. ion) m/z: 208.2 (M+1).

1. customwas bubbled into the solution for 5 min at −78° C
2. customThe mixture was quenched with 2 N HCl (10 ml)
3. customThe resulting mixture was partitioned between 100 ml of Et2O and 1 N NaOH
4. customThe organic layer was separated
5. extractionextracted 3 times with 150 ml Et2O
6. dry with materialThe combined organic extracts were dried over Na2SO4
7. concentrationconcentrated