Benzyl Alcohol → 3-benzyloxy-4-(4-ethylbenzyl)-5-methyl-1H-pyrazole

HRID 2116474Notes

Reaction equation

HRID 2116474 reaction equation
[CH2:1]([C:3]1[CH:16]=[CH:15][C:6]([CH2:7][C:8]2[C:9](=[O:14])[NH:10][NH:11][C:12]=2[CH3:13])=[CH:5][CH:4]=1)[CH3:2].[CH2:17](O)[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.N(C(OCC)=O)=NC(OCC)=O>O1CCCC1>[CH2:17]([O:14][C:9]1[C:8]([CH2:7][C:6]2[CH:5]=[CH:4][C:3]([CH2:1][CH3:2])=[CH:16][CH:15]=2)=[C:12]([CH3:13])[NH:11][N:10]=1)[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1

Participants

6

Reactant 4

HCID 244Benzyl AlcoholHCID 11776TriphenylphosphineHCID 220568ethyl N-ethoxycarbonyliminocarbamateHCID 119840721,2-dihydro-4-(4-ethylbenzyl)-5-methyl-3H-pyrazol-3-one

Product 1

HCID 231036163-benzyloxy-4-(4-ethylbenzyl)-5-methyl-1H-pyrazoleYield 39%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a solution of 1,2-dihydro-4-(4-ethylbenzyl)-5-methyl-3H-pyrazol-3-one (synthesized as described in WO0116147; 1.0 g, 4.6 mmol), benzyl alcohol (600 mg, 5.5 mmol) and triphenylphosphine (1.46 g, 5.5 mmol) in tetrahydrofuran (30 mL), diethyl azodicarboxylate (40% in toluene, 5.1 mmol) was added dropwise under ice cooling. After stirring overnight at room temperature, the reaction mixture was concentrated and the resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=75:25 to 70:30) to give 3-benzyloxy-4-(4-ethylbenzyl)-5-methyl-1H-pyrazole (550 mg, 39%) as a colorless powder.

Workup

  1. concentrationthe reaction mixture was concentrated
  2. customthe resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=75:25 to 70:30)

Sources & evidence

ORD record
ord-1234c723ef774acba291f600488d57a1
Source dataset
uspto-grants-2008_10
Patent number
US07439232B2

Reaction notes

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