反应详情

温度

15 °C

To a 500 ml 3-neck round bottom flask is transferred an ethylmagnesium bromide solution, 100 ml of 3.0M in dried ether, 0.30 mole, under an argon atmosphere. The contents are cooled to about 0° to 3° C. in a solution of 1-decyne, 25 grams, 0.1808 mole, and 50 ml of dried ether are added dropwise into the reaction mixture over a period of 1.5 hours. Thereafter the mixture is warmed to 35°-38° C. and maintained at that temperature for an additional hour. The mixture is then cooled to about 15° C. and powdered iodine, 80 g., 0.315 mole, is slowly added through a solid addition funnel over a period of about 1.5 hours. The reaction is maintained at 30° C. for approximately 2.5 additional hours. In the meantime, an additional 150 ml of dried ether is added to limit the viscosity increase during the reaction. In the work-up process, 200-300 ml of ether are added and the contents hydrolyzed by slowly pouring them into two liters of cold, dilute acetic acid having a pH of about 1-2. The organic phase is extracted with ether and washed several times with 10 percent Na2S2O3 solution to remove the unreacted iodine. Washing continues until the organic phase exhibits a clear color. Following this, the phase is washed several times with water and dried over MgSO4. The solvent is removed by means of a rotary evaporator, and the oily crude product is purified by column chromatography, using silica gel absorbent and hexane as an eluent. The yield is about 90 percent based on 1-decyne used, of a pale yellow liquid, 43.0 grams, 0.1629 mole.

1. customTo a 500 ml 3-neck round bottom flask is transferred
2. additionare added dropwise into the reaction mixture over a period of 1.5 hours
3. temperatureThereafter the mixture is warmed to 35°-38° C.
4. temperaturemaintained at that temperature for an additional hour
5. addition, 0.315 mole, is slowly added through a solid addition funnel over a period of about 1.5 hours
6. temperatureThe reaction is maintained at 30° C. for approximately 2.5 additional hours
7. temperatureincrease during the reaction
8. extractionThe organic phase is extracted with ether
9. washwashed several times with 10 percent Na2S2O3 solution
10. customto remove the unreacted iodine
11. washWashing
12. washis washed several times with water
13. dry with materialdried over MgSO4
14. customThe solvent is removed by means of a rotary evaporator
15. customthe oily crude product is purified by column chromatography