تفاعل #5393

معادلة التفاعل

hydrochloric acid

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

t-butyllithium

dry ice

→

2-carboxy-5,5'-dimethoxybiphenyl

المذيبات

ether

—

Hexanes

water

dimethylformamide

—

hexanes

ether

ظروف التفاعل

المعالجة

1. 1
   أخرىThe resulting solution was transferred to another flask
2. 2
   workup.ADDITIONcontaining
3. 3
   درجة الحرارةto warm to room temperature over a 3-hour period during which time a white precipitate
4. 4
   أخرىhad formed
5. 5
   أخرىThe organic layer was separated
6. 6
   أخرىthe solvents were removed under reduced pressure
7. 7
   أخرىto yield a yellow oil
8. 8
   أخرىto precipitate out
9. 9
   ترشيحThe solids were filtered
10. 10
    أخرى40% ether-hexane mixture to remove impurities
11. 11
    ترشيحThe solid was filtered
12. 12
    أخرىdried in vacuo

الإجراء التجريبي

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.

المصدر