反应详情

A solution of Meldrum's acid (32 g, 22.2 mmol)in methyl orthoformate (200 ml) was stirred at 100° C. 3-Hydroxy-4-methoxyaniline (28 g, 20 mmol) was added and the solution was heated at reflux for 15 minutes. After cooling, the mixture was stirred overnight at ambient temperature. The precipitate was collected by filtration, washed with methyl orthoformate followed by ether and dried under vacuum to give 5-((3-hydroxy-4-methoxyanilino)methylene)-2,2-dimethyl-1,3-dioxane-4,6-dione (47.5 g, 82%).

1. temperaturethe solution was heated
2. temperatureat reflux for 15 minutes
3. temperatureAfter cooling
4. filtrationThe precipitate was collected by filtration
5. washwashed with methyl orthoformate
6. customdried under vacuum