反应详情

To a solution of ethyl 2-(2-amino-1,3-thiazol-4-yl)acetate, which can be represented as ethyl 2-(2-imino-2,3-dihydro-1,3-thiazol-4-yl)acetate, (14 g.) in a mixture of pyridine (40 g.) and methylene chloride (300 ml.) was gradually added diethyl ether solution of tert-pentyl chloroformate (70 ml.) containing 0.35 mole of tert-pentyl chloroformate over 10 minutes at -20° C. with stirring, and the mixture was stirred for 2 hours at the same temperature and further stirred for 0.5 hour at 0° C. After the reaction, the reaction mixture was poured into water (200 ml.), and then the organic layer was separated. The organic layer was washed with 2 N hydrochloric acid, water, 5% sodium bicarbonate aqueous solution and water in turn and then dried over magnesium sulfate. The solvent was distilled off from the organic layer to give dark brown oil of ethyl 2-(2-tert-pentyloxycarbonylamino-1,3-thiazol-4-yl)acetate, which can be represented as ethyl 2-(2-tert-pentyloxycarbonylimino-2,3-dihydro-1,3-thiazol-4-yl)acetate, (12 g.).

1. stirringthe mixture was stirred for 2 hours at the same temperature
2. stirringfurther stirred for 0.5 hour at 0° C
3. customAfter the reaction
4. customthe organic layer was separated
5. washThe organic layer was washed with 2 N hydrochloric acid, water, 5% sodium bicarbonate aqueous solution and water in turn
6. dry with materialdried over magnesium sulfate
7. distillationThe solvent was distilled off from the organic layer