GENERAL METHOD: Tris(2-furyl)phosphine (0.02 mmol, 4.7 mg) was mixed with [Rh(CO)2Cl]2 (0.01 mmol, 3.9 mg) in toluene (10 mL) at room temperature. After stirring for 10 min, a solution of 2-methyl-3-butyn-2-ol (1 mmol) in toluene (1 mL) and pinacolborane (1.2 mmol, 174 μL) were added sequentially to the reaction system. The reaction was stirred at room temperature under nitrogen protection and the progress of the reaction was monitored by thin layer chromatography (TLC). Upon completion of the reaction, the reaction was quenched with water and the reaction mixture was subsequently extracted with ether (Et2O). The organic phases were combined, dried with anhydrous magnesium sulfate (MgSO4) and concentrated under reduced pressure to remove the solvent. Finally, the residue was purified by silica gel column chromatography to afford the target product (E)-2-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3-buten-2-ol.
