[CH2:1](Br)[C:2]#[CH:3].[Mg].[CH2:6]([C:9]1([CH:13]=[O:14])[CH2:12][CH2:11][CH2:10]1)[CH2:7][CH3:8]>CCOCC>[CH2:6]([C:9]1([CH:13]([OH:14])[CH2:3][C:2]#[CH:1])[CH2:12][CH2:11][CH2:10]1)[CH2:7][CH3:8]Propargyl bromide (0.27 mL, 2.4 mmol) was added to a mixture of magnesium (1.1 g, 45 mmol) and mercuric chloride (30 mg, 0.117 mmol) in Et2O (60 mL). The mixture was warmed to 40° C. until bubbling commenced. The remainder of the propargyl bromide (2.1 mL, 19 mmol) was added in small portions. After ˜1.5 h the reaction became cloudy white. A solution of the aldehyde 3 (0.8 g, 7 mmol) in Et2O (4 mL) was added and the reaction was stirred for 16 h. The reaction was then quenched by cautiously adding saturated aqueous NH4Cl. The resultant mixture was extracted with Et2O. The organic portion was washed with brine, dried (MgSO4), filtered and concentrated in vacuo. FCC (silica gel, 1:1 pentane/CH2Cl2) gave 1.0 g (94%) of the alcohol 4.
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