反应详情

温度

120 °C

Into a 100-mL round-bottom flask, was placed 3-chloro-5-(2-methylphenyl)-1,2-thiazole-4-carbonitrile (6 g, 25.56 mmol, 1.00 equiv). This was followed by the addition of sulfuric acid (8 mL). The mixture was stirred at 120° C. for 1 h. To this was added a solution of NaNO2 (3.54 g, 51.30 mmol, 2.01 equiv) in water (5 mL) dropwise with stirring at 0° C. The resulting solution was stirred for 1 h at 50° C. in an oil bath. The resulting solution was extracted with 3×50 mL of ethyl acetate and the organic layers combined, washed with 20 mL 2N HCl, dried over anhydrous sodium sulfate and concentrated under vacuum. This resulted in 5 g (crude) of 3-chloro-5-(2-methylphenyl)-1,2-thiazole-4-carboxylic acid as yellow oil.

1. customInto a 100-mL round-bottom flask, was placed
2. stirringwith stirring at 0° C
3. stirringThe resulting solution was stirred for 1 h at 50° C. in an oil bath
4. extractionThe resulting solution was extracted with 3×50 mL of ethyl acetate
5. washwashed with 20 mL 2N HCl
6. dry with materialdried over anhydrous sodium sulfate
7. concentrationconcentrated under vacuum
8. customThis resulted in 5 g (crude) of 3-chloro-5-(2-methylphenyl)-1,2-thiazole-4-carboxylic acid as yellow oil