Cesium carbonate → 2-(3,5-dimethyl-4-nitro-1H-pyrazol-1-yl)ethanol

Temperatur

90 °C

To a solution of 3,5-dimethyl-4-nitro-1H-pyrazole (500 mg, 3.52 mmol) in MeCN (5 mL), Cs2CO3 (1.26 g, 3.87 mmol) and 2-bromoethanol (0.3 mL, 4.21 mmol) was added. The resulting mixture was refluxed (90° C.) for 3 h, then the reaction mixture was allowed to reach rt. The mixture was diluted with DCM, filtered, the filter cake rinsed with DCM and the filtrate concentrated in vacuo. The residue was partitionned between water and EtOAc, the org. layer was separated and the aq. layer was extracted with EtOAc (1×). The combined org. layers were washed with brine, dried (MgSO4), filtered and concentrated in vacuo to yield 2-(3,5-dimethyl-4-nitro-1H-pyrazol-1-yl)ethanol as a white solid. LC-MS conditions A: tR=0.53 min, [M+H]+=186.39.

1. customto reach rt
2. filtrationfiltered
3. washthe filter cake rinsed with DCM
4. concentrationthe filtrate concentrated in vacuo
5. customlayer was separated
6. extractionthe aq. layer was extracted with EtOAc (1×)
7. washlayers were washed with brine
8. dry with materialdried (MgSO4)
9. filtrationfiltered
10. concentrationconcentrated in vacuo

ORD-Eintrag

ord-37e3e9b30d14439aa2e004f5e331caf0

Quelldatensatz

uspto-grants-2016_04

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09303023B2