Isobutylene oxide → 2-methyl-1-(3-nitro-1H-pyrazol-1-yl)propan-2-ol

HRID 2381278Notes

Reaction equation

HRID 2381278 reaction equation
[N+:1]([C:4]1[CH:8]=[CH:7][NH:6][N:5]=1)([O-:3])=[O:2].C(=O)([O-])[O-].[K+].[K+].[CH3:15][C:16]1([CH3:19])[O:18][CH2:17]1>CN(C)C=O.O>[CH3:15][C:16]([OH:18])([CH3:19])[CH2:17][N:6]1[CH:7]=[CH:8][C:4]([N+:1]([O-:3])=[O:2])=[N:5]1

Participants

6

Reactant 3

HCID 11208Isobutylene oxideHCID 11430Potassium CarbonateHCID 178526745HCID 178526745, compound2×

Product 1

HCID 545944402-methyl-1-(3-nitro-1H-pyrazol-1-yl)propan-2-olYield 54%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6228DimethylformamideSolvent

Conditions

Temperature
100 °C

Procedure

A solution of 3-nitro-1H-pyrazole (Intermediate 2, 200 mg, 1.77 mmol) in N,N-dimethylformamide (5 mL) was treated with potassium carbonate (352 mg, 2.55 mmol) and 1,1-dimethyloxirane (314 mL, 3.54 mmol) and placed in a sealed tube and heated to 100° C. for 1 h. After this time, the reaction was cooled to 25° C., diluted with water (10 mL) and extracted with ethyl acetate (3×10 mL). The organic layers were then combined and dried over sodium sulfate, filtered and concentrated in vacuo. Silica gel column chromatography (AnaLogix, 12 g column, 50-60% ethyl acetate/hexanes) afforded 2-methyl-1-(3-nitro-pyrazol-1-yl)-propan-2-ol (175 mg, 54%) as a clear colorless oil; ES-HRMS m/e calcd for C7H11N3O3 (M+H)+ 186.0873, observed 186.0873. 1H-NMR (300 MHz, CDCl3) δ ppm 1.25 (s, 6H), 2.11 (br s, 1H), 4.18 (s, 2H), 6.92 (d, J=2.4 Hz, 1H), 7.60 (d, J=2.4 Hz, 1H).

Workup

  1. customplaced in a sealed tube
  2. temperatureAfter this time, the reaction was cooled to 25° C.
  3. extractionextracted with ethyl acetate (3×10 mL)
  4. dry with materialdried over sodium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-0066c4c3cc454ca1bf963d9034953962
Source dataset
uspto-grants-2012_09
Patent number
US08258134B2

Reaction notes

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