Реакция #5393

Уравнение реакции

hydrochloric acid

6-bromo-3,3'-dimethoxy-biphenyl

t-butyllithium

dry ice

→

2-carboxy-5,5'-dimethoxybiphenyl

Растворители

ether

—

Hexanes

water

dimethylformamide

—

hexanes

ether

Условия реакции

Обработка

1. 1
   ДругоеThe resulting solution was transferred to another flask
2. 2
   workup.ADDITIONcontaining
3. 3
   Температураto warm to room temperature over a 3-hour period during which time a white precipitate
4. 4
   Другоеhad formed
5. 5
   ДругоеThe organic layer was separated
6. 6
   Другоеthe solvents were removed under reduced pressure
7. 7
   Другоеto yield a yellow oil
8. 8
   Другоеto precipitate out
9. 9
   ФильтрацияThe solids were filtered
10. 10
    Другое40% ether-hexane mixture to remove impurities
11. 11
    ФильтрацияThe solid was filtered
12. 12
    Другоеdried in vacuo

Методика

12.1 g of 6-bromo-3,3'-dimethoxy-biphenyl was dissolved in 100 mL of dry dimethylformamide and the resulting solution was cooled to -60° C. under nitrogen. 55 mL of 1.7 M t-butyllithium in hexanes was added over a 20-minute period. The resulting solution was transferred to another flask containing a mixture of 275 mL of ether and dry ice which effected a lot of gas evolution. The mixture was allowed to warm to room temperature over a 3-hour period during which time a white precipitate had formed. The mixture was diluted with ether and treated with dilute hydrochloric acid and water. The organic layer was separated and the solvents were removed under reduced pressure to yield a yellow oil. Hexanes were added to the oil causing a solid to precipitate out. The solids were filtered and stirred in a 60:40% ether-hexane mixture to remove impurities. The solid was filtered and dried in vacuo to yield 7.82 g of 2-carboxy-5,5'-dimethoxybiphenyl as an off-white solid. The structure was confirmed by NMR and infrared spectroscopy.

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