Реакция #463544

Уравнение реакции

potassium

5-bromo-2-hydroxypyridine

epoxide

(5R)-4-methyl-4-(2,2,2-trifluoroethyl)-5-(4-methylsulfonyl-phenyl)-3,6-dioxabicyclo[3.1.0]hexan-2-one

5-bromo-2-hydroxypyridine

KOH

→

(5R)-3-(5-bromo-2-pyridyloxy)-4-(4-methylsulfonylphenyl)-5-methyl-5-(2,2,2-trifluoroethyl)-5H-furan-2-one

Растворители

dimethylformamide

isopropanol

Условия реакции

Обработка

1. 1
   Другоеfollowed by evaporation to dryness with toluene and high vacuum
2. 2
   Другоеdrying
3. 3
   Температура(0.742 g, 3.5 mmol) and the mixture was warmed up slowly
4. 4
   Температураto reflux for 16 hrs
5. 5
   workup.ADDITIONpoured on icy dilute ammonium chloride and ethyl acetate
6. 6
   Другоеthe organic layer was separated
7. 7
   ПромывкаThe combined organic layers were washed with brine
8. 8
   Сушкаdried with MgSO4
9. 9
   Другоеthe solvents were removed in vacuo
10. 10
    Другоеto yield
11. 11
    Другоеafter purification on silica gel (10% acetone/toluene) the title compound (0.380 g)

Методика

To a 0° C. mixture of the epoxide(0.930 g) from step 1 in dimethylformamide(3 mL) and isopropanol(12 mL) was added the potassium salt of 5-bromo-2-hydroxypyridine, prepared from 5-bromo-2-hydroxypyridine and one equivalent of 8N KOH followed by evaporation to dryness with toluene and high vacuum drying, (0.742 g, 3.5 mmol) and the mixture was warmed up slowly to reflux for 16 hrs. It was then cooled to room temperature and poured on icy dilute ammonium chloride and ethyl acetate; the organic layer was separated and the aqueous further extracted ounce with ethyl acetate. The combined organic layers were washed with brine, dried with MgSO4 and the solvents were removed in vacuo to yield after purification on silica gel (10% acetone/toluene) the title compound (0.380 g).

Источник