Réaction #456704

Équation de réaction

2-Adamantanone

methyl 3-tert-butyldimethylsilyloxy-4-methoxybenzoate

Lithium aluminum hydride

→

[(3-tert-butyldimethylsilyloxy-4-methoxyphenyl)methoxy methylene]adamantane

Rendement 20.9%

Solvants

THF

tetrahydrofuran

Conditions de réaction

Traitement

1. 1
   AutreThe ice-bath was removed
2. 2
   workup.ADDITIONtriethylamine was added to the mixture
3. 3
   TempératureAfter refluxing for 1 hr
4. 4
   workup.ADDITIONthe 2-adamantanone--methyl 3-tert-butyldimethylsilyloxy-4-methoxybenzoate mixture was introduced via a syringe pump over 5 hr period
5. 5
   TempératureThe mixture was refluxed
6. 6
   Autrethe black mixture was partitioned three times between saturated sodium bicarbonate solution and ethyl acetate
7. 7
   LavageThe combined extracts were washed with water and brine
8. 8
   Séchagedried over magnesium sulfate
9. 9
   AutreThe solution was evaporated
10. 10
    Autreto give a tan solid which
11. 11
    Autrewas flash-chromatographed over silica gel
12. 12
    LavageElution with hexane/ethylacetate (15:1)

Mode opératoire

2-Adamantanone (Aldrich, 55 mg, 0.37 mmol) and methyl 3-tert-butyldimethylsilyloxy-4-methoxybenzoate (90 mg, 0.30 mmol, prepared as in Step 2, above) were mixed and dissolved in 0.9 ml of anhydrous tetrahydrofuran (THF). Lithium aluminum hydride (51 mg, 1.34 mmol) was added with stirring to an ice-cold mixture of titanium trichloride (Aldrich, 440 mg, 2.85 mmol) in THF under nitrogen. The ice-bath was removed and triethylamine was added to the mixture. After refluxing for 1 hr, the 2-adamantanone--methyl 3-tert-butyldimethylsilyloxy-4-methoxybenzoate mixture was introduced via a syringe pump over 5 hr period. The mixture was refluxed and stirred for 4 additional hours. After cooling to room temperature, the black mixture was partitioned three times between saturated sodium bicarbonate solution and ethyl acetate . The combined extracts were washed with water and brine and dried over magnesium sulfate. The solution was evaporated to give a tan solid which was flash-chromatographed over silica gel. Elution with hexane/ethylacetate (15:1) afforded 26 mg of [(3-tert-butyldimethylsilyloxy-4-methoxyphenyl)methoxy methylene]adamantane as a colorless oil. NMR(δ): 0.18 (s, 6H), 1.00 (s, 9H), 3.30 (s, 3H), 3.85 (s, 3H).

Source