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

HRID 1915811

Reaktionsgleichung

[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

Komponenten

Reaktionsbedingungen

Temperatur: -40 °C

Versuchsvorschrift

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%). 1H NMR (400 MHz, CDCl3) δ 8.03 (s, 1H), 5.96-5.86 (m, 2H), 4.13 (s, 3H), 3.70 (s, 1H), 2.63-2.54 (m, 2H), 2.41-2.31 (m, 2H), 2.16-2.03 (m, 2H), 2.00-1.92 (m, 2H).

Aufarbeitung

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)

Quellen und Nachweise

ORD-Eintrag: ord-6a49e5f77de74184bfd96bddaf1c40c8
Quelldatensatz: uspto-grants-2013_12
DOI: 10.6084/m9.figshare.5104873.v1
Patentnummer: US08614206B2

Verknüpfte Notizen

Wird geladen…