反应详情

135 g of (2-amino-4-thiazolyl)glyoxylic acid are added whilst cooling with ice to a solution of 245 g of O-(1-diphenylmethoxycarbonyl-1-methylethyl)-hydroxylamine in 400 ml of dimethylformamide. The solution is stirred for 5 hours without cooling, and is then added to 4 l of methanol. In order to complete precipitation, stirring continues for 5 hours at 10°, and the product is then filtered off by suction and dried. 320 g (93%) of the title compound are obtained as colourless crystals.

1. temperaturewithout cooling
2. customprecipitation
3. stirringstirring
4. waitcontinues for 5 hours at 10°
5. filtrationthe product is then filtered off by suction
6. customdried