反应详情

温度

24 °C

To a one liter round bottom flask containing a cold (0° C.) slurry of 67.6 g (0.6756 mol) of aminoacetonitrile hydrochloride and 44.2 ml (0.2702 mol) of diethyl fumarate in 300 ml of ethyl acetate, were added dropwise, over one hour, an aqueous solution of 46.6 g (0.6756 mol) of sodium nitrite dissolved in 90 ml of water. The temperature of the reaction mixture was maintained at about 0° C. during the nitrite addition, then warmed to room temperature (24° C.) where the mixture was stirred for about 3 hours. The organic layer was separated from the aqueous layer and then stirred at room temperature overnight to provide a solution of 5-cyano-4,5-dihydro-3H-pyrazole-3,4-dicarboxylic acid diethyl ester dissolved in ethyl acetate.

1. additionwere added dropwise, over one hour
2. customThe organic layer was separated from the aqueous layer
3. stirringstirred at room temperature overnight