Реакция #79367

Уравнение реакции

tetrahydro-4H-pyran-4-one

magnesium

4-benzyloxy bromobenzene

→

4-(4-benzyloxyphenyl)tetrahydro-2H-pyran-4-ol

Выход 55.1%

Растворители

THF

Условия реакции

Обработка

1. 1
   ДругоеIn a 100 ml round-bottomed flask was placed
2. 2
   Другоеover 15 min
3. 3
   Температураwith occasional heating by a heat gun
4. 4
   workup.ADDITIONAfter the addition
5. 5
   Температураupon cooling in an ice-water bath
6. 6
   workup.STIRRINGAfter stirring for 30 min
7. 7
   Другоеthe solvent was removed under reduced pressure
8. 8
   workup.ADDITIONdiluted with AcOEt and sat. NH4Cl aq. The organic phase
9. 9
   Другоеwas separated
10. 10
    Концентрированиеconcentrated
11. 11
    Другоеchromatographed on silica gel eluting with 40% AcOEt/hexanes

Методика

In a 100 ml round-bottomed flask was placed magnesium turnings (1.85 g, 76.1 mmol), which was stirred under vacuum without solvent overnight. To it were slowly added anhydrous THF 40 ml and 4-benzyloxy bromobenzene (10 g, 38 mmol) over 15 min with occasional heating by a heat gun to keep the Grignard reagent formation going. After the addition was complete, the resulting gray slurry was stirred for 1 hr at 60° C. To it was added tetrahydro-4H-pyran-4-one (3.5 ml, 38 mmol) upon cooling in an ice-water bath. After stirring for 30 min, the solvent was removed under reduced pressure and diluted with AcOEt and sat. NH4Cl aq. The organic phase was separated, concentrated, and chromatographed on silica gel eluting with 40% AcOEt/hexanes to give 4-(4-benzyloxyphenyl)tetrahydro-2H-pyran-4-ol 5.95 g (55%).

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