反应详情

温度

40 °C

A solution of 2-picolinic acid (540 mg, 4.4 mmol) in dichloromethane (5 ml) was treated with thionyl chloride (0.4 ml, 5.5 mmol) and a drop of DMF at ambient temperature. The reaction mixture is stirred at 40° C. overnight whereupon another equivalent of thionyl chloride was added and stirring was continued at 40° C. for another 2 h. All volatiles were removed and the acid chloride was suspended in dichloromethane (5 ml) and added to a pre-cooled (0° C.) solution of amino-cyano-acetic acid ethyl ester (470 mg, 3.7 mmol) and triethylamine (2.5 ml, 18.3 mmol) in dichloromethane (5 ml). The resulting reaction mixture was slowly warmed-up to 40° C. and stirred at that temperature for 4 h. The reaction mixture was partitioned between potassium hydrogen sulfate (10% aqueous solution) and dichloromethane and extracted. The organic phase was washed with water and brine, dried and the solvent was evaporated. The product was obtained after purification by silica gel chromatography using a heptane/ethyl acetate gradient as light yellow viscous oil (334 mg, 39%).

1. customat ambient temperature
2. additionwas added
3. customAll volatiles were removed
4. additionadded to
5. customThe resulting reaction mixture
6. stirringstirred at that temperature for 4 h
7. customThe reaction mixture was partitioned between potassium hydrogen sulfate (10% aqueous solution) and dichloromethane
8. extractionextracted
9. washThe organic phase was washed with water and brine
10. customdried
11. customthe solvent was evaporated
12. customThe product was obtained
13. customafter purification by silica gel chromatography