反应详情

To a stirred solution of ethyl acetoacetate (150.0 g, 0.86 mol) in hexanes (200 mL) was added phosphorus pentachloride (95.0 g, 0.456 mol) at 23° C. under nitrogen and stirred for 3 h. Water (300 mL) was added to the reaction mixture while cooling in an ice-bath. The organic layer was separated, washed with an aqueous solution of 20% potassium carbonate (3×200 mL) followed by a saturated sodium chloride solution (2×100 mL), dried over sodium sulfate and concentrated in vacuo to afford 3-chloro-but-2-enoic acid ethyl ester which was purified by distillation (95.8 g, 75%): boiling range 160°-170° C.

1. temperaturewhile cooling in an ice-bath
2. customThe organic layer was separated
3. washwashed with an aqueous solution of 20% potassium carbonate (3×200 mL)
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated in vacuo