反应详情

At room temperature under shielded light, to N,N′-diisopropylcarbodiimide (99.75 g) was added copper(I) chloride (1.57 g), and then tert-butanol (83 ml) was added dropwise over 20 minutes, followed by stirring for 4 days. The supernatant (78 ml) was added dropwise to a dichloromethane suspension (270 ml) of 3-bromo-2,2-dimethylpropanoic acid (49.4 g) at room temperature over 30 minutes, followed by stirring for 18 hours. Acetic acid (18.8 ml) was added, and stirred for 1 hour. The reaction suspension was filtered, and ice water and sodium hydrogen carbonate were added to the filtrate for neutralization. After the precipitate was filtered off, the organic layer separated from the filtrate was washed with saturated sodium hydrogen carbonate, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. After pentane was added to the residue, insolubles were filtered off, and the filtrate was concentrated under reduced pressure to afford tert-butyl 3-bromo-2,2-dimethylpropanoic acid (18.81 g).

1. stirringby stirring for 18 hours
2. stirringstirred for 1 hour
3. filtrationThe reaction suspension was filtered
4. additionice water and sodium hydrogen carbonate were added to the filtrate for neutralization
5. filtrationAfter the precipitate was filtered off
6. customthe organic layer separated from the filtrate
7. washwas washed with saturated sodium hydrogen carbonate
8. dry with materialdried over anhydrous sodium sulfate
9. concentrationconcentrated under reduced pressure
10. additionAfter pentane was added to the residue, insolubles
11. filtrationwere filtered off
12. concentrationthe filtrate was concentrated under reduced pressure