Reaktion #75924

Reaktionsgleichung

[3,5-difluoro-4-(methylthio)-phenyl]-methanol

methanesulfonylchloride

HCl

→

5-(chloromethyl)-1,3-difluoro-2-(methylthio)benzene

Ausbeute 95.0%

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe mixture was heated
2. 2
   Temperaturto reflux for 2 hours
3. 3
   Temperaturcooled
4. 4
   workup.STIRRINGstirred at room temperature for 18 hours
5. 5
   Extraktionextracted with dichloromethane once (75 mL)
6. 6
   Sonstigeafter separating
7. 7
   WaschenThe combined extracts were washed with dilute sodium chloride
8. 8
   Sonstigedried
9. 9
   Einengenconcentrated
10. 10
    SonstigePurification by silica gel chromatography

Vorschrift

To a solution of [3,5-difluoro-4-(methylthio)-phenyl]-methanol (24.0 g, 0.126 mol) in dichloromethane (300 mL) cooled in an ice bath was added methanesulfonylchloride (16.9 g, 0.147 mol) in portions followed by disopropyl-ethylamine in portions. The mixture was allowed to warm to room temperature, and stirred for 18 hours. 4-dimethyl-aminopyridine was added and the mixture was heated to reflux for 2 hours, cooled, and stirred at room temperature for 18 hours. The mixture was poured into dilute HCl and extracted with dichloromethane once (75 mL) after separating. The combined extracts were washed with dilute sodium chloride, dried using magnesium sulfate, and concentrated. Purification by silica gel chromatography using 5% ethyl acetate in hexanes gave 5-(chloromethyl)-1,3-difluoro-2-(methylthio)benzene as a clear colorless liquid (24.9 g, 95%). 1H NMR (CDCl3/400 MHz) 6.92-6.96 (m, 2H), 4.49 (s, 2H), 2.44 (s, 3H). HRMS m/z 207.9893 (M+, calcd 207.9925).

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