Benzene → HCID 54421021, compound

Participants

Reaction Steps

A solution of ethyl 2-hydroxyiminoacetoacetate (3.98 g.) and pyridine (1.98 g.) in benzene (25 ml.) was dropwise added to a solution of phosgene (2.48 g.) in benzene (30 ml.) over 30 minutes at 4° to 5° C. After stirring for 1 hour at the same temperature, the mixture was stirred for 1 hour at room temperature and allowed to stand overnight. To the resultant solution containing ethyl 2-chlorocarbonyloxyiminoacetoacetate was dropwise added, over 30 minutes at 5° to 7° C, a solution of tert-butyl alcohol (3.7 g.) and pyridine (3.96 g.) in benzene (25 ml.). After stirring for 1 hour at the same temperature, the reaction temperature was slowly elevated to room temperature, after which the mixture was stirred for 6 hours at the same temperature and allowed to stand overnight. A precipitate was dissolved by adding about same volume of water to that of the organic layer to the reaction mixture, after which the aqueous layer was separated. The organic layer was in turn washed with a 0.5M citric acid aqueous solution, a 5% sodium carbonate aqueous solution and a sodium chloride aqueous solution, and dried over magnesium sulfate. After drying the solvent was distilled off to give ethyl 2-tert-butoxycarbonyloxyiminoacetoacetate (3.7 g.), oil.

Provenance & Evidence