反应详情

2.66 g (0.01 mol) of allyl 2-(2-amino-4-thiazolyl)-2-[(Z)-(cyanomethoxy)imino]-acetate in 100 ml of ethyl acetate are treated while stirring with 17.73 mg (0.0001 mol) of palladium chloride and 0.083 ml (0.0005 mol) of triethyl phosphate. After the addition of 1.54 ml (0.011 mol) of triethylamine, the mixture is stirred at room temperature for 24 hours. Crude 2-(2-amino-4-thiazolyl)-2-[(Z)-(cyanomethoxy)imino]-acetic acid triethylamine salt precipitates out. The filtered-off crude salt (2.9 g) is dissolved in 30 ml of methanol. The solution is adjusted to pH 3 with 2N aqueous hydrochloric acid. Crystallization occurs. The crystals obtained are filtered off and washed with methanol and ether. There are obtained 1.24 g (51.2%) of 2-(2-amino-4-thiazolyl)-2-[(Z)-(cyanomethoxy)imino]-acetic acid of melting point 140°-142° C. (decomposition).

1. customCrude 2-(2-amino-4-thiazolyl)-2-[(Z)-(cyanomethoxy)imino]-acetic acid triethylamine salt precipitates out
2. dissolutionThe filtered-off crude salt (2.9 g) is dissolved in 30 ml of methanol
3. customCrystallization
4. customThe crystals obtained
5. filtrationare filtered off
6. washwashed with methanol and ether