4-(4-bromophenyl)-2-methylbut-3-yn-2-ol

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

Procedure: In a four necked flask equipped with a stirrer, a reflux condenser and a thermometer which had been replaced by a nitrogen atmosphere, 4-(3-hydroxy-3,3-dimethyl-1-propynyl)-1-bromobenzene (3.6 g, 15 mmol), tetrakis(triphenylphosphine)palladium (0.06 g, 0.05 mmol), sodium hydroxide (0.8 g, 20 mmol) and tetrahydrofuran (60 ml) were charged. Then, to the mixture, a solution of E-1-pentenylcatecholborane prepared in Reference Example 1 (20 mmol) in tetrahydrofuran (50 ml) was dropwise added at room temperature, followed by heat refluxing for 6 hours while stirring. After cooling the reaction mixture to room temperature, 30% aqueous hydrogen peroxide (2 ml) was added to the mixture, followed by stirring for 1 hour. The mixture was extracted with toluene and water. The organic layer was washed with water twice and dried over anhydrous magnesium sulfate. After removing the solvents, the residue was purified by silica gel column chromatography to obtain 4-(3-hydroxy-3,3-dimethyl-1-propynyl)-1-(1-trans-pentenyl)benzene (2.8 g). Yield: 83%. Melting point: 65° C. In a four necked flask equipped with a stirrer, a reflux condenser were charged was dropwise added at room temperature by heat refluxing for 6 hours by stirring for 1 hour The mixture was extracted with toluene and water The organic layer was washed with water twice dried over anhydrous magnesium sulfate After removing the solvents the residue was purified by silica gel column chromatography