Ethyl cyanoacetate → 2,4-Dioxo-3-azaspiro(5.5)undecane-1,5-dicarbonitrile

Participants

Reaction Steps

98 g (1 mol) of cyclohexanone, 113 g (1 mol) of ethyl cyanoacetate, 84 g (1 mol) of cyanoacetamide, and 100 ml of methanol were mixed in a reaction flask. 101 g (1 mol) of triethylamine was added dropwise under stirring, and the reaction mixture was stirred for 8 hours with the temperature controlled within the range of 25° C. to 30° C., and then was cooled and filtered. The filter cake was suspended in water, and the suspension was adjusted to pH 2-3 with concentrated hydrochloric acid while stirring. The suspension was filtered, washed with water, and dried to provide 1,5-dicyano-2,4-dioxo-3-azaspiro[5,5]-undecane. Yield: 88%, melting point: 202 to 210° C.

Provenance & Evidence