14267-92-6

5390-04-5

14267-92-6

General procedure for the synthesis of 5-chloro-1-pentyne from 4-pentyn-1-ol: The reaction system was first cooled to 15 °C, followed by the addition of 540 g (6.42 mol) of 4-pentyn-1-ol and 682 g (6.74 mol) of triethylamine to 975 g (7.70 mol) of o-chlorotoluene with stirring and mixing. 772 g (6.74 mol) of methanesulfonyl chloride was slowly added dropwise over a period of 2 h. The internal temperature of the reaction was controlled to be maintained between 15-20 °C. After the dropwise addition was completed, stirring was continued for 30 minutes to ensure that the reaction was complete and the reaction mixture was obtained. Subsequently, the reaction mixture was heated to 90 °C and stirred continuously at this temperature for 2 hours. After completion of the reaction, the mixture was cooled to room temperature. Triethylamine and methanesulfonyl chloride derived by-products were removed from the reaction mixture by washing with water. The organic phase was separated and dried with magnesium sulfate to give 1651 g of organic phase containing 581 g (5.66 mol) of 5-chloro-1-pentynylene in 88.2% reaction yield. The organic phase was mainly composed of o-chlorotoluene (boiling point: 159 °C) and 5-chloro-1-pentyne (boiling point: 113 °C). Finally, the organic phase was purified by decompression distillation to give 584.2 g of 5-chloro-1-pentynyne with 98.2% purity, and the yield of the distillation process was 98.4%.