Citric Acid → HCID 18630238, compound

Temperature

-78 °C

2-Bromobenzoic acid (30.15 g, 150 mmol), THF (400 mL), and diisopropyl amine (33.4 g, 330 mmol) were stirred under nitrogen and cooled to -78° C. 10M n-BuLi in hexanes (31 mL, 0.31 mol) was then added dropwise, followed by the dropwise addition of TMSCl (17.4 g, 160 mmol). The mixture was allowed to slowly warm to -30° C., stirred for 1 h, then was poured into 25% citric acid (100 mL) and stirred for 15 min. The mixture was extracted with two 100 mL portions of ether, which were combined and washed three times with sat aq NaHCO3 solution. The bicarbonate solution was acidified with 25% citric acid and extracted with three 100 mL portions of ether. These extracts were combined, dried (MgSO4), and concentrated. The crude product was purified by recrystallization from ether/hexanes, and the desired product was recovered as a white solid in 35% yield. m.p. 139°-141° C.

1. temperatureto slowly warm to -30° C.
2. stirringstirred for 15 min
3. extractionThe mixture was extracted with two 100 mL portions of ether, which
4. washwashed three times with sat aq NaHCO3 solution
5. extractionextracted with three 100 mL portions of ether
6. dry with materialdried (MgSO4)
7. concentrationconcentrated
8. customThe crude product was purified by recrystallization from ether/hexanes
9. customthe desired product was recovered as a white solid in 35% yield

ORD record

ord-8351d22f105b4e62814fb43a8281b205

Source dataset

uspto-grants-1998_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05705513