反应详情

Under ice-cooling, sodium hydride (4.65 g, content 60%) was added in small portions to a THF solution (300 ml) containing (2E)-3-(4-methoxyphenyl)acrylaldehyde (10 g) synthesized by the process described in Reference Example 1 and ethyl 2-(diethoxyphosphoryl)-3-oxo-3,4-dihydro-2H-1,4-benzothiazine-6-carboxylate (21.7 g, synthesized according to the process disclosed in WO00/63197). The resulting mixture was slowly warmed up to room temperature and stirred overnight. The same aldehyde as above (1.5 g) was added thereto and stirred for another 2 hours. The resulting mixture was concentrated under reduced pressure, and ethyl acetate (30 ml), hexane (100 ml), a 1N aqueous hydrochloric acid solution (50 ml) and water (600 ml) were added to the residue, followed by stirring at room temperature for 6 hours. The solid was collected by filtration and dried under reduced pressure. Ethyl 2-[3-(4-methoxyphenyl)prop-2-en-1-ylidene]-3-oxo-3,4-dihydro-2H-1,4-benzothiazine-6-carboxylate (22.43 g) was obtained as a yellow solid.

1. temperatureUnder ice-cooling
2. customsynthesized by the process
3. customsynthesized
4. stirringstirred for another 2 hours
5. concentrationThe resulting mixture was concentrated under reduced pressure, and ethyl acetate (30 ml), hexane (100 ml)
6. additiona 1N aqueous hydrochloric acid solution (50 ml) and water (600 ml) were added to the residue
7. stirringby stirring at room temperature for 6 hours
8. filtrationThe solid was collected by filtration
9. customdried under reduced pressure