Acetonitrile → HCID 21768519, compound

HRID 1725665Notes

Reaction equation

HRID 1725665 reaction equation
C(#N)C.[CH2:4]([O:6][C:7]([C:9]1[NH:13][N:12]=[C:11]([CH3:14])[CH:10]=1)=[O:8])[CH3:5].[CH2:15](Br)[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1.C([O-])([O-])=O.[K+].[K+]>O>[CH2:4]([O:6][C:7]([C:9]1[N:13]([CH2:15][C:16]2[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=2)[N:12]=[C:11]([CH3:14])[CH:10]=1)=[O:8])[CH3:5]

Participants

6

Reactant 4

HCID 6342AcetonitrileHCID 7498Benzyl BromideHCID 11430Potassium CarbonateHCID 178469061HCID 178469061, compound

Product 1

HCID 21768519HCID 21768519, compoundYield 38.4%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

An acetonitrile (8.0 mL) mixture of ethyl-3-methyl-1H-pyrazole-5-carboxylate (15) (0.50 g. 3.2 mmol), benzyl bromide (0.48 mL, 4.0 mmol), and K2CO3 (0.90 g, 6.5 mmol) was stirred at room temperature overnight. The reaction mixture was diluted with water (50 mL) and extracted with dichloromethane. The combined organic layers were washed with brine and dried over anhydrous magnesium sulfate. After removal of solvent under reduced pressure, the residue was purified by flash column chromatography [silica gel, eluting with mixtures of ethyl acetate and hexanes (0% ramped to 15% EtOAc/hexanes)] to yield 0.30 g of ethyl-1-benzyl-3-methylpyrazole-5-carboxylate (16). 1H NMR (CDCl3): δ 7.30-7.22 (m, 5H), 6.65 (s, 1H), 5.71(s, 2H), 4.28 (q, J=7.2 Hz, 2H), 2.32 (s, 3H), 1.32 (t, J=7.2 Hz, 3H); LCMS: purity: 99%; MS (m/z): 345(MH+).

Workup

  1. extractionextracted with dichloromethane
  2. washThe combined organic layers were washed with brine
  3. dry with materialdried over anhydrous magnesium sulfate
  4. customAfter removal of solvent under reduced pressure
  5. customthe residue was purified by flash column chromatography [silica gel, eluting with mixtures of ethyl acetate and hexanes (0% ramped to 15% EtOAc/hexanes)]

Sources & evidence

ORD record
ord-f4db0e58a61445f99670c2bdb16cbf79
Source dataset
uspto-grants-2009_02
Patent number
US07491732B2

Reaction notes

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