Adamantanone → [(3-Tert-butyldimethylsilyloxy-4-methoxyphenyl)methoxy methylene]adamantane

Participants

Reaction Steps

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).

Provenance & Evidence