反应详情

A mixture of 2-(4-thiazolyl)glyoxylic acid (2.3 g) in methanol (23 ml) and t-butyl 2-aminooxyacetate (2.6 g) was stirred for an hour at ambient temperature. The reaction mixture was added to a mixture of ethyl acetate and water and adjusted to pH 7.5 with saturated aqueous solution of sodium bicarbonate. The separated aqueous layer was adjusted to pH 2.0 with 10% hydrochloric acid and the mixture was saturated sodium chloride. The acidic mixture was extracted with ethyl acetate. The extract layer was washed with saturated aqueous solution of sodium chloride, dried over magnesium sulfate and evaporated to give 2-t-butoxycarbonylmethoxyimino-2-(4-thiazolyl)acetic acid (syn isomer) (2.8 g), mp. 136°-139° C.

1. extractionThe acidic mixture was extracted with ethyl acetate
2. washThe extract layer was washed with saturated aqueous solution of sodium chloride
3. dry with materialdried over magnesium sulfate
4. customevaporated