30 g of N-ethylethanolamine, 1.2 g of tetrabutylammonium bromide, 25 g of potassium hydroxide, 240 g of chloroform,120g of water was added to the reaction flask, and then the temperature was controlled at 20 to 30 ° C, 38 g of 5-chloro-2-pentanone was added dropwise, and after the addition was completed, the mixture was stirred.Should be 3 hours, static layering, the water phase is discarded, the organic layer is added 24g anhydrous sodium sulfate, the temperature is controlled at 10 ~ 20 ° C, stirred and dried 1Hour, filtration, the filtrate is the organic phase of the condensation product, the content of which is detected, the condensation product is 51.7g, and the molar yield is 94.7% (to 5-Chloro-2-pentanone), GC purity ≧ 98.5%.