Hydrochloric Acid → 4-(3-Chloro-phenyl)-2-(5-formyl-2-nitro-phenylamino)-thiazole-5-carboxylic acid amide

Participants

Reaction Steps

A mixture of 3.2 g (7.1 mmole) of 4-(3-chloro-phenyl)-2-(5-dimethoxymethyl-2-nitro-phenylamino)-thiazole-5-carboxylic acid amide (VI.2a), 30 mL of 2M hydrochloric acid and 5 mL of dimethylformamide was stirred at 60 degrees for 3 hours. The mixture was cooled and then concentrated under reduced pressure. The residue was taken up in 100 mL of dichloromethane and washed once with 100 mL of saturated sodium bicarbonate solution, once with 50 mL of brine, and then dried over anhydrous sodium sulfate. The mixture was filtered and concentrated under reduced pressure. The residue was purified by silica gel chromatography, eluting with hexanes-ethyl acetate (50:50) to give 2.5 g of 4-(3-chloro-phenyl)-2-(5-formyl-2-nitro-phenylamino)-thiazole-5-carboxylic acid amide (VI.2b).

Provenance & Evidence