Dimethylamine → Ethyl 2-Chloro-4-dimethylcarbamoyl-thiazole-5-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 2-chloro-5 (ethoxy carbonyl)-1,3-thiazole-4-carboxylic acid (Intermediate 7, 2 g, 8.01 mmol) in dry dichloromethane (20 mL) was added oxalyl chloride (1.37 mL, 16.02 mmol) and 2 drops of dry dimethylformamide. The reaction mixture was heated to 45° C. for 90 minutes. After the completion of the reaction, the reaction mixture was evaporated to dryness under reduced pressure. The residue was dissolved in dry dichloromethane (20 mL) and was cooled to 0° C., then 2,6-lutidine (0.97 mL, 8.4 mmol) was added followed by addition of N,N-dimethylamine (2 M solution in tetra hydro furan, 4.19 mL, 8.4 mmol). After completion of the reaction, the reaction mixture was concentrated to dryness and the residue was extracted with ethyl acetate (2×50 mL). The organic layer was washed with 1 N hydrochloric acid, water and brine (1×50 mL), and concentrated after drying over anhydrous sodium sulfate to afford 1.6 g (72.7%) of the title compound as a thick syrup.

Provenance & Evidence