Hydrochloric Acid → 2-(2-Aminothiazol-4-yl)-2-(2-hydroxyethoxyimino)acetic acid

Participants

Reaction Steps

A mixture of ethyl 2-(2-benzoyloxyethoxyimino)-2-(2-aminothiazol-4-yl)acetate (syn isomer) (8.5 g.), 1N aqueous sodium hydroxide (35 ml.), methanol (40 ml.) and tetrahydrofuran (40 ml.) was stirred at 35° to 40° C. for 9 hours and at ambient temperature for 12 hours. After adjusting the resultant solution to pH 6.5 with conc. hydrochloric acid, the solution was concentrated to about 2/3 volume of the initial. The concentrate was adjusted to pH 3.5 with conc. hydrochloric acid under ice-cooling, and the precipitates were collected by filtration, washed with water and acetone in turn and then dried over phosphorus pentoxide under reduced pressure to give 2-(2-hydroxyethoxyimino)-2-(2-aminothiazol-4-yl)acetic acid (syn isomer) (3.3 g.).

Provenance & Evidence