Sodium Iodide → 4-[2-(3,4-Dimethoxy-phenyl)-ethyl]-piperazine-1-carboxylic acid t-butyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A reaction mixture of 4-(2-chloroethyl)-1,2-dimethoxybenzene (3.6 g, 17.9 mmol), piperazine-1-carboxylic acid t-butyl ester (4.0 g, 21.5 mmol), K2CO3 (4.97 g, 36 mmol), and NaI (2.7 g, 18 mmol) in DMF (20 mL) was stirred at 80° C. for 3 h, cooled to room temperature, and partitioned between water and ethyl acetate. The organic layer was washed with water and brine, dried over anhydrous sodium sulfate, and concentrated. The residue was purified by column chromatography to afford 4-[2-(3,4-dimethoxy-phenyl)-ethyl]-piperazine-1-carboxylic acid t-butyl ester (4.8 g, 76%) which was dissolved in 4 N HCl in dioxane. This solution was stirred at room temperature for 4 h, concentrated, and dried in a high vacuum oven to give the title compound quantitatively.

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