Reaktion #60272

Reaktionsgleichung

6-(4-Bromo-2-chloro-phenylamino)-7-fluoro-3H-benzoimidazole-5-carboxylic acid methyl ester

K2CO3

t-butyl acrylate

→

desired product

Ausbeute 62.3%

6-(4-Bromo-2-chloro-phenylamino)-3-(2-tert-butoxycarbonyl-ethyl)-7-fluoro-3H-benzoimidazole-5-carboxylic acid methyl ester

Ausbeute 62.3%

Lösungsmittel

DMF

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe reaction mixture is cooled to room temperature
2. 2
   WaschenThe organic layer is washed with water (3×) and brine
3. 3
   Trocknendried (MgSO4)
4. 4
   Einengenconcentrated under reduced pressure
5. 5
   SonstigePurification by flash column chromatography
6. 6
   Wascheneluted with 19:1 methylene chloride

Vorschrift

6-(4-Bromo-2-chloro-phenylamino)-7-fluoro-3H-benzoimidazole-5-carboxylic acid methyl ester 8b (0.50 g, 1.25 mmol) is dissolved in DMF (8 mL) under N2 and K2CO3 (0.26 g, 1.88 mmol) is added followed by t-butyl acrylate (1.84 mL, 12.54 mmol). The reaction mixture is heated to 90° C. with stirring. After 4 hours, the reaction mixture is cooled to room temperature and diluted with ethyl acetate. The organic layer is washed with water (3×) and brine, dried (MgSO4) and concentrated under reduced pressure. Purification by flash column chromatography eluted with 19:1 methylene chloride:ethyl acetate provides 0.41 g (62%) desired product.

Quelle