反应详情

To a solution of 2,6-diamino-4,5-dihydronicotinic acid ethyl ester described in Preparation Example A-13 (4.5 g, 24.6 mmol) in tetrahydrofuran (300 mL) was added 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (5.6 g, 24.7 mmol), which was then stirred for 40 minutes at room temperature. The residue obtained by concentrating the reaction solution was then purified by NH silica gel column chromatography (ethyl acetate) to obtain a solid of the target compound. This solid was washed with hexane and dried to obtain the title compound (3.1 g, 17.1 mmol, 69.5%).

1. customThe residue obtained
2. concentrationby concentrating the reaction solution
3. customwas then purified by NH silica gel column chromatography (ethyl acetate)
4. customto obtain a solid of the target compound
5. washThis solid was washed with hexane
6. customdried