反应详情

A combination of 10 g Intermediate B and 8 g N,N-diphenylformamidine was thoroughly mixed and heated with stirring at 150°-160° C. for 25 minutes. The flask was then fitted with a condenser and 50 ml hot acetone was cautiously added. An orange precipitate formed. The flask was removed from the heat, cooled, and chilled in ice. After 1 hour, the reddish precipitate was filtered off and discarded. The filtrate was poured into 300 ml diethyl ether and stirred for 2 hors. The resulting yellow-orange powder was filtered, washed with ether, and dried to yield 10.6 g of 2-(2-anilinovinyl)-3-ethyl-5-hexylsulfonamidobenzoxazolium p-toluenesulfonate (Intermediate C).

1. temperatureheated
2. customThe flask was then fitted with a condenser
3. customAn orange precipitate formed
4. customThe flask was removed from the heat
5. temperaturecooled
6. temperaturechilled in ice
7. waitAfter 1 hour
8. filtrationthe reddish precipitate was filtered off
9. additionThe filtrate was poured into 300 ml diethyl ether
10. stirringstirred for 2 hors
11. filtrationThe resulting yellow-orange powder was filtered
12. washwashed with ether
13. customdried