Answer :
Final answer:
A primary alcohol is synthesized by reacting a Grignard reagent with methanal, forming a new C-C bond. A suitable alkyl halide is used to prepare the Grignard reagent, which is reacted with methanal to obtain the desired alcohol upon acidic workup.
Explanation:
The synthesis of alcohol by the reaction of a Grignard reagent with methanal involves the formation of a primary alcohol. This reaction begins with the preparation of a suitable Grignard reagent, which is typically an alkyl magnesium bromide.
The general formula for synthesizing a Grignard reagent is the reaction of an alkyl halide (RX, where X = Cl, Br, I) with magnesium metal in an ether solvent. When this Grignard reagent is added to methanal (formaldehyde), the result is the formation of a new carbon-carbon bond, yielding a primary alcohol after the addition is worked up with water (H₂O).
In practice, if we want to synthesize a primary alcohol using methanal and a Grignard reagent, we would choose an alkyl halide that when reacted with magnesium would form the Grignard reagent. This Grignard reagent would then be reacted with methanal, and the resulting addition product would be treated with water or another suitable acid to produce the desired alcohol.
For example, if allylmagnesium chloride is used as the Grignard reagent, addition to methanal followed by an acidic workup will yield the corresponding primary alcohol with two carbon atoms more than the original allyl group.
