Dimethylformamide → 4-NITRO-2H-PYRAZOLE-3-CARBOXAMIDE

4-Nitro-2H-pyrazole-3-carboxylic acid (2.72 g, 17.4 mmol) was added to a solution of oxalyl chloride (2.42 mL, 27.7 mmol) and N,N-dimethylformamide (80 μL) in dichloromethane (45 mL) and the reaction mixture stirred at room temperature for 2 hours. The reaction mixture was concentrated in vacuo and azeotroped from dichloromethane (3×100 mL). The crude product was dissolved in tetrahydrofuran, cooled in an ice bath, and treated with 0.880 ammonia solution (20 mL). The reaction mixture was stirred at room temperature for 18 hours then concentrated in vacuo and the residue partitioned between dichloromethane (300 mL) and water (100 mL). The organic layer was separated, dried over magnesium sulphate and concentrated in vacuo to yield the title product. LRMS ES+m/z 157 [MH]+

1. concentrationThe reaction mixture was concentrated in vacuo
2. customazeotroped from dichloromethane (3×100 mL)
3. dissolutionThe crude product was dissolved in tetrahydrofuran
4. temperaturecooled in an ice bath
5. additiontreated with 0.880 ammonia solution (20 mL)
6. stirringThe reaction mixture was stirred at room temperature for 18 hours
7. concentrationthen concentrated in vacuo
8. customthe residue partitioned between dichloromethane (300 mL) and water (100 mL)
9. customThe organic layer was separated
10. dry with materialdried over magnesium sulphate
11. concentrationconcentrated in vacuo

ORD record

ord-99bc1a503eb84b7689f8f43c175456ae

Source dataset

uspto-grants-2007_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07262192B2