Ethyl Acetate → [(3-tert-Butyldimethylsilyloxyphenyl) (2-chloroethoxy)methylene]adamantane

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Reaction Steps

A three neck flask was purged with argon and charged with 400 mL of anhydrous THF. Titanium trichloride (48 g, 0.3 mol) was added with stirring and the flask was cooled in an ice bath. Lithium aluminum hydride (6.0 g, 0.16 mol) was added in small portions causing a brief exothermic reaction. After all of the LAH was added, the cooling bath was removed and the mixture warmed to room temperature. Triethylamine (30 mL) was added and the black mixture was refluxed for 1.5 hours under argon. A solution of adamantanone (14 g, 93 mmol) and 2-chloroethyl 3-t-butyldimethylsilyloxybenzoate (10 g, 31 mmol) in 50 mL of dry THF was added dropwise while reflux was continued. After an additional 10 min, TLC (5% ethyl acetate in hexane) indicated conversion of the ester to new material so the mixture was cooled and diluted with 3 L of hexane. The hexane was decanted, filtered through filter paper and evaporated leaving an oil which was purified by column chromatography on silica gel, eluting with 0-3% ethyl acetate in hexane yielding 8.68 g of alkene (65% based on ester); 1H NMR (CDCl3) δ0.195 (s,6H), 0.983 (s,9H), 1.78-1.98 (m,12H), 2.65 (br s,1H), 3.334 (br s,1H), 3.55 (t,2H), 3.66 (t,2H), 6.85-7.29 (m,4H). ##STR14##

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