Trifluoroacetic acid → HCID 86724100, compound

To a solution of 1-methyl-5-nitro-1H-pyrazole-3-carbohydrazide (3.81 g, 20.6 mmol) in DCM (30 mL) was added 2,2,2-trifluoroacetic acid (4 mL, 51.9 mmol). The mixture was stirred for about 2 h then concentrated under reduced pressure. To the residue was added triethoxymethane (31.4 mL, 206 mmol) and the mixture was refluxed for about 24 h. The reaction was cooled to ambient temperature and continued to stir for about 16 h. The reaction mixture was concentrated under reduced pressure and the material was partitioned between DCM (25 mL) and saturated NaHCO3 (10 mL). The organic layer was separated and the aqueous layer was back extracted with DCM (25 mL). The combined organic layers were washed with brine (10 mL), dried over MgSO4, filtered and concentrated under reduced pressure and triturated with ether (2×30 mL).

1. concentrationthen concentrated under reduced pressure
2. temperaturethe mixture was refluxed for about 24 h
3. stirringto stir for about 16 h
4. concentrationThe reaction mixture was concentrated under reduced pressure
5. customthe material was partitioned between DCM (25 mL) and saturated NaHCO3 (10 mL)
6. customThe organic layer was separated
7. extractionthe aqueous layer was back extracted with DCM (25 mL)
8. washThe combined organic layers were washed with brine (10 mL)
9. dry with materialdried over MgSO4
10. filtrationfiltered
11. concentrationconcentrated under reduced pressure
12. customtriturated with ether (2×30 mL)

ORD record

ord-c7e0537a03454d5392759c30eba8c6d3

Source dataset

uspto-grants-2015_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09150592B2