Reaktion #1828912

Reaktionsgleichung

NaHCO3

POCl3

triethylamine

5-(4-fluorophenyl)-2-methylpyridine-N-oxide

POCl3

→

5-(4-fluorophenyl)-2-(chloromethyl)pyridine

Lösungsmittel

CH2Cl2

CH2Cl2

CH2Cl2

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturso as to maintain
2. 2
   Temperaturreflux
3. 3
   workup.ADDITIONAfter addition
4. 4
   SonstigeThe organic phase is separated
5. 5
   Trocknendried over MgSO4
6. 6
   Einengenconcentrated in vacuo

Vorschrift

To a solution of 5-(4-fluorophenyl)-2-methylpyridine-N-oxide (2.9 g, 14.5 mmol) in CH2Cl2 (15 mL) is added a 1.5 mL portion of a CH2Cl2 (15 mL) solution of POCl3 (1.72 g, 1.7 mmol). Subsequently, the remainder of this POCl3 solution and a solution of triethylamine (1.76 g, 17.4 mmol) in CH2Cl2 (15 mL) are added simultaneously, so as to maintain reflux. After addition is complete the resulting solution is stirred at ambient temperature for 2 hours. The reaction mixture is then neutralized by addition of saturated NaHCO3 (50 mL). The organic phase is separated, dried over MgSO4 and concentrated in vacuo. Chromatography (silica gel, 1:1 EtOAc/hexanes) affords 5-(4-fluorophenyl)-2-(chloromethyl)pyridine as a yellow solid.

Quelle