反应详情

(Z)-2-Hydroxyimino-2-(2-tritylaminothiazol-4-yl)acetic acid (4.2 g) as a suspension in dichloromethane (150 ml) was treated with a solution of diphenyldiazomethane (1.91 g) in dichloromethane (50 ml) in a dropwise fashion, over 5 min. After 2 h stirring at room temperature, acetic acid (1 ml) was added and stirred for a further 30 min. The solution was washed with saturated sodium bicarbonate and water, dried and filtered. Removal of solvent in vacuo gave a yellow crisp foam which was purified by chromatography on silica gel eluting with ethyl acetate/hexane. The title compound was obtained as a white solid; νmax (CH2Cl2) 1735, 1520 and 1490 cm-1 ; δH (CDCl3) 6.16 (1H, s), 7.17 (1H, s). 7.22-7.50 (25H, m). [Mass spectrum: +ve ion (thioglycerol) MNa+ (596)].

1. stirringstirred for a further 30 min
2. washThe solution was washed with saturated sodium bicarbonate and water
3. customdried
4. filtrationfiltered
5. customRemoval of solvent in vacuo
6. customgave a yellow crisp foam which
7. customwas purified by chromatography on silica gel eluting with ethyl acetate/hexane