1-methyl-4-nitro-1H-pyrazole → (Z)-1-(1-methyl-4-nitro-1H-pyrazol-5-yl)cyclohept-4-enol

HRID 521942

Reaction equation

[CH3:1][N:2]1[CH:6]=[C:5]([N+:7]([O-:9])=[O:8])[CH:4]=[N:3]1.[C:10]1(=[O:17])[CH2:16][CH2:15][CH:14]=[CH:13][CH2:12][CH2:11]1.C[Si](C)(C)[N-][Si](C)(C)C.[Li+].[Cl-].[NH4+]>C1COCC1>[CH3:1][N:2]1[C:6]([C:10]2([OH:17])[CH2:16][CH2:15][CH:14]=[CH:13][CH2:12][CH2:11]2)=[C:5]([N+:7]([O-:9])=[O:8])[CH:4]=[N:3]1

Participants

Conditions

Temperature: -40 °C

Procedure

To a solution of 1-methyl-4-nitro-1H-pyrazole (1.5 g, 11.8 mmol) and (Z)-cyclohept-4-enone (1.4 g, 13.0 mmol) in dry THF (30 mL) under nitrogen cooled to −78° C. was added dropwise a solution of lithium hexamethyldisilazide (1.0 M in THF, 30 mL, 29.5 mmol). The reaction mixture was allowed to warm to −40° C. and stirred for 90 min. Saturated aqueous ammonium chloride solution (30 mL) was added (dropwise initially) and the mixture was allowed to warm to room temperature and extracted with EtOAc (150 mL). The organic layer was washed with water (30 mL), washed with brine (20 mL), separated, dried over MgSO4 and concentrated under reduced pressure. Purification via silica gel column chromatography (20-25% EtOAc) gave (Z)-1-(1-methyl-4-nitro-1H-pyrazol-5-yl)cyclohept-4-enol as a tan oil (1.37 g, 49%).

Workup

temperatureto warm to room temperature
extractionextracted with EtOAc (150 mL)
washThe organic layer was washed with water (30 mL)
washwashed with brine (20 mL)
customseparated
dry with materialdried over MgSO4
concentrationconcentrated under reduced pressure
customPurification via silica gel column chromatography (20-25% EtOAc)

Sources & evidence

ORD record: ord-2fc1cce7738e49f3a797f537f2d6e4e8
Source dataset: uspto-grants-2016_05
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09328106B2

Linked notes

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