Phosgene → HCID 12298225, compound

Participants

Reaction Steps

Phosgene gas is introduced through a stirring mixture of 29.2 parts of 4-anilino-1-(ethoxycarbonyl)isonipecotic acid in 240 parts of dioxane: exothermic reaction (temperature rises to 45° C.). Stirring is continued for 30 minutes at 45° C. The mixture is heated to reflux and phosgene gas is gently introduced for 2 h. 30. Then nitrogen gas is introduced for 30 minutes. The reaction mixture is evaporated in a boiling water-bath for 30 minutes. The solid residue is triturated in ether, yielding ethyl 2,4-dioxo-1-phenyl-3-oxa-1,8-diazaspiro[4,5]decane-8-carboxylate; mp. 210.7° C.

Provenance & Evidence