Potassium Carbonate → 3-{5-[N-(2-(3,4-dimethyloxyphenyl)-ethyl)-N-methylaminocarbonyl]-pentyloxy}-5-(3,4-dimethoxyphenyl)-pyrazole

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

3.85 g of 5-(3,4-dimethoxyphenyl)-pyrazolin-3-one were dissolved in 50 ml of anhydrous dimethylformamide. 3.15 g of finely ground potassium carbonate were added to the solution, and the reaction mixture was heated under a nitrogen atmosphere to 100° C. with stirring. A solution of 5.6 g of 5-{N-[2-(3,4-dimethoxyphenyl)-ethyl]-N-methylaminocarbonyl}-pentyl bromide in 10 ml of anhydrous dimethyl formamide was slowly added dropwise to the solution, and the reaction mixture was stirred at 100° C. for a further 2 hours. In order to work up the reaction mixture, it was cooled and then the precipitated salts were filtered out and the filtrate was concentrated by evaporation. The oily residue which remained was dissolved in ethyl acetate and washed with 7% strength sodium hydroxide solution in order to remove unreacted 5-(3,4-dimethoxyphenyl)-pyrazolin-3-one. The organic phase was separated, dried with sodium sulfate and concentrated by evaporation. 6.5 g of 3-{5-[N-(2-(3,4-dimethyloxyphenyl)-ethyl)-N-methylaminocarbonyl]-pentyloxy}-5-(3,4-dimethoxyphenyl)-pyrazole were obtained as an oil.

Herkunft & Nachweise