(3E)-5-bromopenta-1,3-diene

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Under a nitrogen atmosphere, to a stirred solution of sodium (0.53 g, 23 mmol) in 2-methoxyethanol (50 mL) at room temperature was added 5-bromo-(3E)-1,3-pentadiene (3.38 g, 23 mmol). The mixture was stirred overnight and then refluxed for three more hours. Excess 2-methoxyethanol was removed by distillation. Water was added to the cooled reaction mixture, which was then extracted with diethyl ether. The diethyl ether solution was dried over MgSO4, then stripped off at reduced pressure. Distillation at 87-88° C., 31 mmHg (water aspirator) yielded 2.46 g (75%) of the desired compound. refluxed for three more hours Excess 2-methoxyethanol was removed by distillation Water was added to the cooled reaction mixture, which was then extracted with diethyl ether The diethyl ether solution was dried over MgSO4 Distillation at 87-88° C.

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: The starting material is 228 g (4.0 mol) of 1-amino-2-propene. 58.8 g (0.4 mol) of (E)-1-bromo-2,4-pentadiene (title compound of Example A.1.) are added dropwise, with stirring. The internal temperature is kept in the range 20°-30° C. by cooling. The reaction mixture is stirred for 5 h at room temperature and concentrated at 150 mbar. A solution of 20 g (0.5 mol) of sodium hydroxide in 200 ml of water is added, the mixture is extracted with twice 100 ml of methylene chloride, the extracts are dried over sodium sulphate, 0.1 g of 4-hydroxyanisole is added and the mixture is concentrated and distilled at 40 mbar. The distillate is stabilized by the addition of 10-20 ppm of 4-hydroxyanisole.

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Initially introduce 228 g (4.0 mol) of 1-amino-2-propene. Add 58.8 g (0.4 mol) of (E)-1-bromo-2,4-pentadiene (title compound from Example A.1.) dropwise with stirring. Keep the internal temperature in the range from 20°-30° C. by cooling. Stir at room temperature for 5 h. Concentrate the mixture at 150 mbar. Add 20 g (0.5 mol) of sodium hydroxide dissolved in 200 ml of water, extract twice with 100 ml of methylene chloride each time, dry with sodium sulphate, add 0.1 g of 4-hydroxyanisole, concentrate and distil at 40 mbar. For stabilization, 10-20 ppm of 4-hydroxyanisole are added to the distillate.

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Introduce 228 g (4.0 mol) of 1-amino-2-propene. Add dropwise with stirring 58.8 g (0.4 mol) of (E)-1-bromo-2,4-pentadiene (title compound of Example A.1.). Keep the internal temperature in a range of 20°-30° C. by means of cooling. Stir for 5 h at room temperature. Concentrate batch at 150 mbar. Add 20 g (0.5 mol) of sodium hydroxide, dissolved in 200 ml of water, extract the mixture twice using in each case 100 ml of methylene chloride, dry using sodium sulphate, add 0.1 g of 4-hydroxyanisole, concentrate and distil at 40 mbar. 10-20 ppm of 4-hydroxyanisole are added to stabilize the distillate. Add dropwise

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Under a nitrogen atmosphere, to a stirred solution of sodium (0.53 g, 23 mmol) in 2-methoxyethanol (50 mL) at room temperature was added 5-bromo-(3E)-1,3-pentadiene (3.38 g, 23 mmol). The mixture was stirred overnight and then refluxed for three more hours. Excess 2-methoxyethanol was removed by distillation. Water was added to the cooled reaction mixture, which was then extracted with diethyl ether. The diethyl ether solution was dried over MgSO4, then stripped off at reduced pressure. Distillation at 87-88° C., 31 mmHg (water aspirator) yielded 2.46 g (75%) of the desired compound. refluxed for three more hours Excess 2-methoxyethanol was removed by distillation Water was added to the cooled reaction mixture, which was then extracted with diethyl ether The diethyl ether solution was dried over MgSO4 Distillation at 87-88° C.