tert-Butanol → 937040-09-0

HRID 336837Notes

Reaction equation

HRID 336837 reaction equation
[N+:1]([C:4]1[NH:8][N:7]=[C:6](C(O)=O)[CH:5]=1)([O-:3])=[O:2].C1(OP([N:28]=[N+]=[N-])(=O)OC2C=CC=CC=2)C=CC=CC=1.C(N(CC)CC)C.[C:38](=[O:41])([O-])[O-:39].[K+].[K+].[C:44](O)([CH3:47])([CH3:46])[CH3:45]>>[N+:1]([C:4]1[NH:8][N:7]=[C:6]([NH:28][C:38](=[O:41])[O:39][C:44]([CH3:47])([CH3:46])[CH3:45])[CH:5]=1)([O-:3])=[O:2]

Participants

6

Reactant 5

HCID 6386tert-ButanolHCID 8471TriethylamineHCID 11430Potassium CarbonateHCID 123414Diphenylphosphoryl azideHCID 862226845-Nitro-1H-pyrazole-3-carboxylic acid

Product 1

HCID 135971896937040-09-0

Procedure

To 10 g (63.66 mmol) of 5-nitro-1H-pyrazole-3-carboxylic acid are respectively added 39 ml of tert-butanol, 27.44 ml (127.3 mmol) of diphenylphosphorazidate and 17.7 ml (127.32 mmol) of triethylamine. The solution is refluxed for 8 h, then an aqueous solution saturated with potassium carbonate is added until reaching pH 8, and the product is extracted several times with ethyl acetate. The organic phases are combined, dried over magnesium sulfate, and concentrated. The residue obtained is triturated in methanol to give 4.38 g of tert-butyl 5-nitro-1H-pyrazol-3-ylcarbamate in the form of a yellow solid. The filtrate is concentrated and purified by chromatography on silica (cyclohexane/ethyl acetate eluent: 7:3) to yield an additional 1.49 g of tert-butyl 5-nitro-1H-pyrazol-3-ylcarbamate in the form of a yellow solid.

Workup

  1. temperatureThe solution is refluxed for 8 h
  2. extractionthe product is extracted several times with ethyl acetate
  3. dry with materialdried over magnesium sulfate
  4. concentrationconcentrated
  5. customThe residue obtained
  6. customis triturated in methanol

Sources & evidence

ORD record
ord-52f8fe2e15e2415694cb6554a8830328
Source dataset
uspto-grants-2014_11
Patent number
US08889711B2

Reaction notes

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