Реакция #1836

Уравнение реакции

Cyclohexene

bromine

2-[2-(1H-tetrazol-5-yl)phenyl]-5-methylbenzofuran

1,4-dioxane

→

product

Выход 85.0%

3-Bromo-2-[2-(1H-tetrazol-5-yl)phenyl]-5-methylbenzofuran

Выход 85.0%

Растворители

carbon tetrachloride

Условия реакции

Обработка

1. 1
   ДругоеA 1 L 3-neck round bottom flask equipped with a magnetic stirrer
2. 2
   Концентрированиеit was concentrated under vacuum to an oily residue that
3. 3
   Другоеwas partitioned between 100 mL of 1N aqueous sodium hydroxide and 100 mL of ether
4. 4
   ДругоеThe aqueous layer was removed
5. 5
   Экстракцияextracted several times with ethyl acetate
6. 6
   ПромывкаThe combined extracts were washed with saturated aqueous sodium chloride
7. 7
   Сушкаdried over magnesium sulfate
8. 8
   Фильтрацияfiltered
9. 9
   Концентрированиеconcentrated under vacuum
10. 10
    Другоеto give a white foam that
11. 11
    Другоеwas triturated with 100 mL of hot toluene
12. 12
    ТемператураThe mixture was cooled in an ice bath
13. 13
    Другоеthe solids removed by filtration
14. 14
    Промывкаthen washed with cold toluene, air
15. 15
    Другоеdried
16. 16
    Другоеdried under vacuum

Методика

A 1 L 3-neck round bottom flask equipped with a magnetic stirrer, thermometer, dropping funnel and nitrogen bubbler was charged with 12.97 g (46.9 mmol) of 2-[2-(1H-tetrazol-5-yl)phenyl]-5-methylbenzofuran and 500 mL of 1,4-dioxane. To the well-stirred solution at room temperature was added a solution of 4.8 mL (93.2 mmol) of bromine in 35 mL of carbon tetrachloride dropwise over 1 hour. Cyclohexene (16 mL) was added to the reaction mixture then it was concentrated under vacuum to an oily residue that was partitioned between 100 mL of 1N aqueous sodium hydroxide and 100 mL of ether. The aqueous layer was removed, acidified with 50 mL of 2N aqueous hydrochloric acid, and extracted several times with ethyl acetate. The combined extracts were washed with saturated aqueous sodium chloride, dried over magnesium sulfate, filtered and concentrated under vacuum to give a white foam that was triturated with 100 mL of hot toluene. The mixture was cooled in an ice bath and the solids removed by filtration then washed with cold toluene, air dried and dried under vacuum to give 14.11 g (39.7 mmol, 85%) of product. 1H NMR (200 MHz,CDCl3 +1 drop DMSO-d6): 2.44 (s,3H), 7.1-7.3 (m,4H), 7.6 (m,2H), 7.86 (m,1H), 7.95 (m,1H).

Источник