Potassium Carbonate → 1-(3,4-dimethylphenyl)-3-nitro-1H-pyrazole

Temperature

85 °C

Into a 250-mL round bottom flask purged and maintained with an inert atmosphere of nitrogen, was placed a solution of 3-nitro-1H-pyrazole (6 g, 53.10 mmol, 1.00 equiv) in DMSO (80 mL), 4-bromo-1,2-dimethylbenzene (11.8 g, 64.13 mmol, 1.21 equiv), CuI (1.6 g, 8.42 mmol, 0.16 equiv), L-proline (1 g, 8.70 mmol, 0.16 equiv), and potassium carbonate (14.6 g, 105.80 mmol, 1.99 equiv). The resulting solution was stirred overnight at 85° C. in an oil bath. The reaction progress was monitored by LCMS. The resulting solution was diluted with 300 mL of water. The resulting solution was extracted with 4×100 mL of ethyl acetate and the organic layers combined. The resulting mixture was washed with 3×100 mL of water and 1×100 mL of brine. The mixture was dried over anhydrous sodium sulfate. The solids were filtered out. The resulting mixture was concentrated under vacuum. The residue was applied onto a silica gel column and eluted with ethyl acetate/petroleum ether (1:10) to give 1 g (9%) of 1-(3,4-dimethylphenyl)-3-nitro-1H-pyrazole as a yellow solid.

1. customInto a 250-mL round bottom flask purged
2. temperaturemaintained with an inert atmosphere of nitrogen
3. extractionThe resulting solution was extracted with 4×100 mL of ethyl acetate
4. washThe resulting mixture was washed with 3×100 mL of water and 1×100 mL of brine
5. dry with materialThe mixture was dried over anhydrous sodium sulfate
6. filtrationThe solids were filtered out
7. concentrationThe resulting mixture was concentrated under vacuum
8. washeluted with ethyl acetate/petroleum ether (1:10)

ORD record

ord-be3f983de45e4e2581df79a4ea9ecf7e

Source dataset

uspto-grants-2016_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09289430B2