反应详情

1.075 g of methyl (3-cyano-4,5-dihydroxyphenyl)-glyoxylate and 0.60 g of 2-amino-p-cresol are stirred at 120° for 70 minutes in 2 ml of dimethylformamide. The mixture is subsequently cooled to room temperature and diluted with 15 ml of water. The precipitate is filtered and dried in a water-jet vacuum at 80° for 6 hours. After recrystallization from acetonitrile there is obtained 2,3-dihydroxy-5-(6-methyl-2-oxo-2H-1,4-benzoxazin-3-yl)-benzonitrile of m.p. 278°-280°.

1. filtrationThe precipitate is filtered
2. dry with materialdried in a water-jet vacuum at 80° for 6 hours
3. customAfter recrystallization from acetonitrile