反应详情

温度

-60 °C

12.1 g of 2-bromo-5,5'-dimethoxybiphenyl 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.

1. customThe resulting solution was transferred to another flask
2. additioncontaining
3. temperatureto warm to room temperature over a 3-hour period during which time a white precipitate
4. customhad formed
5. customThe organic layer was separated
6. customthe solvents were removed under reduced pressure
7. customto yield a yellow oil
8. customto precipitate out
9. filtrationThe solids were filtered
10. custom40% ether-hexane mixture to remove impurities
11. filtrationThe solid was filtered
12. customdried in vacuo