Sodium hydride → [3-(3-Nitro-pyrazol-1-ylmethyl)-phenyl]-carbamic acid tert-butyl ester

HRID 546094

Reaction equation

HRID 546094 reaction equation
[N+:1]([C:4]1[CH:8]=[CH:7][NH:6][N:5]=1)([O-:3])=[O:2].[H-].[Na+].[C:11]([O:15][C:16](=[O:26])[NH:17][C:18]1[CH:23]=[CH:22][CH:21]=[C:20]([CH2:24]Br)[CH:19]=1)([CH3:14])([CH3:13])[CH3:12]>CN(C)C=O.C(OCC)(=O)C>[C:11]([O:15][C:16](=[O:26])[NH:17][C:18]1[CH:23]=[CH:22][CH:21]=[C:20]([CH2:24][N:6]2[CH:7]=[CH:8][C:4]([N+:1]([O-:3])=[O:2])=[N:5]2)[CH:19]=1)([CH3:14])([CH3:13])[CH3:12]

Participants

6

Reactant 3

HCID 24758Sodium hydrideHCID 14523558tert-Butyl 3-(bromomethyl)phenylcarbamateHCID 178526745HCID 178526745, compound

Product 1

HCID 67194378[3-(3-Nitro-pyrazol-1-ylmethyl)-phenyl]-carbamic acid tert-butyl esterYield 47%

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideSolventHCID 8857Ethyl AcetateSolvent

Conditions

Temperature
0 °C

Procedure

3-Nitro-1H-pyrazole (prepared in example 3, 595 mg, 5.26 mmol) was dissolved in anhydrous N,N-dimethylformamide (10 mL) and a 60% dispersion of sodium hydride in mineral oil (211 mg, 5.28 mmol) was added while stirring under nitrogen. After the effervescence ceased and the reaction stirred for an additional 25 min, the reaction was chilled to 0° C. and (3-bromomethyl-phenyl)-carbamic acid tert-butyl ester (1.50 g, 5.26 mmol) was added. The reaction continued to stir under nitrogen at 0° C. for 20 min. The reaction was diluted with ethyl acetate (200 mL), washed with water (2×50 mL), saturated aqueous brine solution (2×20 mL), dried over magnesium sulfate and concentrated in vacuo to give a yellow oil. Purification by flash column (Merck silica gel 60, 40-63 μm; 15% ethyl acetate/hexanes) followed by recrystallization from methylene chloride afforded [3-(3-nitro-pyrazol-1-ylmethyl)-phenyl]-carbamic acid tert-butyl ester (782 mg, 47%) as a beige solid: H1-NMR (400 MHz, DMSO-d6) δ 1.45 (9H, s), 5.39 (2H, s), 6.88 (1H, d, J=7.6 Hz), 7.06 (1H, d, J=2.4 Hz), 7.22 (1H, t, J=8.0 Hz), 7.35 (1H, d, J=8.0 Hz), 7.40 (1H, s), 8.11 (1H, d, J=2.8 Hz), 9.36 (1H, s).

Workup

  1. stirringthe reaction stirred for an additional 25 min
  2. stirringto stir under nitrogen at 0° C. for 20 min
  3. washwashed with water (2×50 mL), saturated aqueous brine solution (2×20 mL)
  4. dry with materialdried over magnesium sulfate
  5. concentrationconcentrated in vacuo
  6. customto give a yellow oil
  7. customPurification by flash column (Merck silica gel 60, 40-63 μm; 15% ethyl acetate/hexanes)
  8. customfollowed by recrystallization from methylene chloride

Sources & evidence

ORD record
ord-fe46e71163464c3cab459d6066d8711b
Source dataset
uspto-grants-2011_05
Patent number
US07935699B2

Linked notes

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