Alternate Retrosynthesis of an Alcohol

Since sp-hybridized carbons are relatively acidic (pKa=25), strong bases can be used to deprotonate a terminal alkyne. If a Grignard reagent is used as the base, then the resulting product is drawn as a Grignard rather than an anion (this essentially sacrifices a more reactive, cheaper Grignard in the production of a new, more stable one— the desired alkynyl Grignard). 

Alkynyl Grignard Reagents Are Prepared from a Grignard Base 

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