Dimethylformamide → 4-(3-Chloro-phenyl)-2-(5-dimethoxymethyl-2-nitro-phenylamino)-thiazole-5-carboxylic acid ethyl ester

Beteiligte Stoffe

Reaktionsschritte

A mixture of 2.82 g (10 mmole) of 2-amino-4-(3-chloro-phenyl)-thiazole-5-carboxylic acid ethyl ester, 9.75 g (30 mmole) of cesium carbonate, 20 mL of dimethylformamide, and 2.15 g (10 mmole) of 4-dimethoxymethyl-2-fluoro-1-nitro-benzene was heated at 80 degrees for 1 hour. The cooled mixture was diluted with 200 mL of water and extracted three times with 100 mL of dichloromethane. The combined organic layers were washed with brine, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified with silica gel chromatography, eluting with ethyl acetate-hexanes (gradient 0:100-10:90) to give 3.4 g of 4-(3-chloro-phenyl)-2-(5-dimethoxymethyl-2-nitro-phenylamino)-thiazole-5-carboxylic acid ethyl ester (VI.41a) as a yellow solid.

Herkunft & Nachweise