9-(t-Butyldimethylsilyloxy)-1-nonyne → 4-[9-(t-Butyldimethylsilyloxy)-1-nonynyl]4-hydroxy-7-methoxymethoxy-3-(4-methoxymethoxyphenyl)-3-methylchroman

Participants

Reaction Conditions

Reaction Steps

9-(t-Butyl dimethylsilyloxy)-1-nonyne (7.1 g, 27.9 mmol) was dissolved in dry tetrahydrofuran (70 mL) under argon atmosphere, which was then cooled down to −78° C. n-Butyllithium (15.1 ml, 25.1 mmol, 1.66 mol/l solution in tetrahydrofuran) was slowly added dropwise thereto, and the mixture was stirred at −20° C. for 80 minutes. To this mixture was added dropwise 7-methoxymethoxy-3-(4-methoxymethoxyphenyl)-3-methylchroman-4-one (2.0 g, 5.58 mmol) dissolved in dry tetrahydrofuran (15 mL) at −20° C., and the resulting reaction mixture was stirred at the same temperature for 3 hours, and then stirred at −10° C. overnight. The reaction was quenched with water, and the reaction solution was extracted with ethyl acetate. The organic layer was washed with water and saturated sodium chloride solution, dried over anhydrous magnesium sulfate, and concentrated. The residue was subjected to flash chromatography on silica gel (n-hexane:ethyl acetate=9:1) to give the title compound (3.37 g, yield 99%) as a colorless oil.

Provenance & Evidence