2,2,6,6-Tetramethylpiperidine → 2-Bromo-3-fluoro-5-(4-octyloxyphenyl)pyrazine

HRID 864265Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 864265
CC1(C)CCCC(C)(C)N1.C([Li])CCC.[F:16][C:17]1[CH:22]=[N:21][CH:20]=[C:19]([C:23]2[CH:28]=[CH:27][C:26]([O:29][CH2:30][CH2:31][CH2:32][CH2:33][CH2:34][CH2:35][CH2:36][CH3:37])=[CH:25][CH:24]=2)[N:18]=1.[Br:38]Br>CCCCCC.O1CCCC1>[Br:38][C:22]1[C:17]([F:16])=[N:18][C:19]([C:23]2[CH:28]=[CH:27][C:26]([O:29][CH2:30][CH2:31][CH2:32][CH2:33][CH2:34][CH2:35][CH2:36][CH3:37])=[CH:25][CH:24]=2)=[CH:20][N:21]=1

Komponenten

7

Edukt 4

HCID 130352,2,6,6-TetramethylpiperidineHCID 24408BromineHCID 218046342-Fluoro-6-(4-octyloxyphenyl)pyrazineHCID 178418339Butyllithium

Produkt 1

HCID 218046332-Bromo-3-fluoro-5-(4-octyloxyphenyl)pyrazine

Reagenzien, Katalysatoren, Lösungsmittel 2

HCID 8028TetrahydrofuranLösungsmittel3×HCID 8058HexaneLösungsmittel

Reaktionsbedingungen

Temperatur
-78 °C

Versuchsvorschrift

3.50 g (24.8 mmol) of 2,2,6,6-tetramethylpiperidine and 15.50 ml (24.80 mmol) of 1.6 M n-butyllithium solution in hexane are stirred at 0° C. for 0.5 hour in 80 ml of tetrahydrofuran, 250 ml of tetrahydrofuran are added, and the mixture is cooled to -78° C. 5.00 g (16.5 mmol) of 2-fluoro-6-(4-octyloxyphenyl)pyrazine in 150 ml of tetrahydrofuran and, after the mixture has been stirred for one hour, 0.85 ml of bromine are subsequently added dropwise at -78C. The reaction mixture is stirred overnight, during which it warms to room temperature, and is partitioned between ether and aqueous sodium chloride solution, the aqueous phase is washed with aqueous sodium chloride solution, dried over sodium sulfate, filtered and freed from the solvent, and the residue is purified by chromatography (silica/hexane: ethyl acetate = 9:1). 4.68 g of 2-bromo-3-fluoro-5-(4-octyloxyphenyl)pyrazine are obtained. ##STR16## 1d

Aufarbeitung

  1. customwarms to room temperature
  2. customis partitioned between ether and aqueous sodium chloride solution
  3. washthe aqueous phase is washed with aqueous sodium chloride solution
  4. dry with materialdried over sodium sulfate
  5. filtrationfiltered
  6. customthe residue is purified by chromatography (silica/hexane: ethyl acetate = 9:1)

Quellen und Nachweise

ORD-Eintrag
ord-4af11b7138bf4c79a2c71c4cbb5fe6c7
Quelldatensatz
uspto-grants-1996_10
Patentnummer
US05562859

Notizen zur Reaktion

Wird geladen…