反应详情

After adding 25 ml of trifluoroacetic acid to a solution of 3.30 g of 3-(N′-t-butoxycarbonylhydrazino)-1H-pyrazole-4-carboxylic acid ethyl ester in 50 ml of dichloromethane, the mixture was stirred for 2 hours at room temperature. Next, 100 ml of toluene was added and the solvent was removed under reduced pressure. The residue was dissolved in a small amount of methanol, and after adding a 4N solution containing hydrochloric acid in ethyl acetate until the solution reached acidic, the solvent was removed under reduced pressure. The residue was treated with 50 ml of t-butyl methyl ether, and the solid was filtered off and dried under reduced pressure to give the title compound (3.30 g) as a white solid.

1. customthe solvent was removed under reduced pressure
2. dissolutionThe residue was dissolved in a small amount of methanol
3. additionafter adding a 4N solution
4. additioncontaining hydrochloric acid in ethyl acetate until the solution
5. customthe solvent was removed under reduced pressure
6. additionThe residue was treated with 50 ml of t-butyl methyl ether
7. filtrationthe solid was filtered off
8. customdried under reduced pressure