反应详情

As represented by the following reaction pathway, 30% fuming sulfuric acid (2.1-liter) was added to 300 g of acenaphtho[1,2-b]quinoxaline obtained by synthesis example 1 and the mixture was stirred at room temperature for 48 hours for reaction. While keeping the obtained solution at 40° C. to 50° C., 4.5-liter of ion exchange water was added for dilution, and the resultant was further stirred for 3 hours. The precipitate was filtered to obtain acenaphtho[1,2-b]quinoxaline-2-sulfonic acid as represented by the following formula (d).

1. customobtained by synthesis example 1
2. customat 40° C. to 50° C.
3. stirringthe resultant was further stirred for 3 hours
4. filtrationThe precipitate was filtered