反应详情

A solution of 1,2,3,4-tetrahydro-8-methyl-9-nitro-5H-[1]benzopyrano[3,4-c]pyridin-5-one (6.0 g, 0.023 moles) in N,N-dimethylformamide (100 ml) and methanol (50 ml) is hydrogenated at 50 psi in the presence of Raney Nickel (0.5 g) at room temperature for 20 hours. Additional Raney Nickel (0.5 g) in N,N-dimethylformamide (50 ml) is then added, and hydrogenation resumed until hydrogen uptake ceases. The catalyst is filtered off and rinsed with warm N,N-dimethylformamide. The filtrate is concentrated under reduced pressure and filtered to afford the product (4.3 g), mp 283°-284° C.

1. filtrationThe catalyst is filtered off
2. washrinsed with warm N,N-dimethylformamide
3. concentrationThe filtrate is concentrated under reduced pressure
4. filtrationfiltered