101597-25-5

90-96-0

1066-54-2

101597-25-5

Trimethylsilylacetylene (4.5 g, 45 mmol) was dissolved in anhydrous tetrahydrofuran (150 mL) under nitrogen protection and cooled to -10°C. n-Butyllithium (1.6 M hexanes solution, 28.5 mL, 45 mmol) was slowly added, the temperature was maintained at -10°C, and the reaction mixture was stirred for 1 hour. Subsequently, a solution of anhydrous tetrahydrofuran (75 mL) of 4,4'-dimethoxybenzophenone (7.44 g, 40.8 mmol) was added dropwise at the same temperature. Stirring was continued at -10°C for 3 h. The reaction system was then slowly warmed to 0°C. A methanol (40.8 mL) solution of sodium hydroxide (2.16 g, 54 mmol) was added, followed by gradual warming of the reaction mixture to room temperature. The pH of the reaction solution was adjusted to 7 with acetic acid and the mixture was poured into water (546 mL). The aqueous phase was extracted with ethyl acetate (3 x 105 mL), the organic layers were combined and dried with anhydrous magnesium sulfate. After concentration under reduced pressure, the crude product was recrystallized by ethyl acetate/petroleum ether mixed solvent to give 7.5 g of 1,1-bis(4-methoxyphenyl)-2-propyn-1-ol (1c) as a light yellow solid in 88.4% yield.