1-bromo-4-pent-4-enylbenzene

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 1.13 g of 4-(4-pentenyl)-bromobenzene in 20 ml of tetrahydrofuran wa added dropwise 4 ml of 1.5 M n-butyl lithium in n-hexane with dry-ice - acetone cooling, and the mixture was stirred for 15 minutes. To the reaction mixture was added 0.58 ml of dimethylformamide and stirred for an hour. Then the reaction mixture, after addition of 50 ml of water, was extracted with ether. The organic layer was washed with water and dried. Evaporation of the solvent under reduced pressure gave 850 mg of 4-(4-pentenyl)benzaldehyde. stirred for an hour was extracted with ether The organic layer was washed with water dried Evaporation of the solvent under reduced pressure

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of 970 mg of magnesium in 20 ml of tetrahydrofuran was added dropwise a solution of 5.4 g of 4-bromo-1-butene in 20 ml of tetrahydrofuran while keeping at 50° C. Then, a solution of 10.0 g of 4-bromobenzyl bromide in 20 ml of tetrahydrofuran was added dropwise slowly, and the mixture was refluxed for an hour, made acidic with dilute hydrochloric acid and extracted with n-hexane. The organic layer was washed with water and dried over magnesium sulfate. The solvent was evaporated under reduced pressure, and the residue was chromatographed on silica gel column with n-hexane to give 1.14 g of 4-(4-pentenyl)bromobenzene. while keeping at 50° C the mixture was refluxed for an hour extracted with n-hexane The organic layer was washed with water dried over magnesium sulfate The solvent was evaporated under reduced pressure the residue was chromatographed on silica gel column with n-hexane