Grignard reaction of methylmagnesium bromide with benzaldehyde yields which alcohol after workup?

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Multiple Choice

Grignard reaction of methylmagnesium bromide with benzaldehyde yields which alcohol after workup?

Grignard reagents add to carbonyl compounds to form alcohols after acidic workup, with the group from the Grignard becoming a new substituent on the carbon that bears the OH. Here, a methyl Grignard adds to benzaldehyde (Ph-CHO). The carbonyl carbon receives the methyl group, and after hydrolysis the oxygen is protonated to give an alkoxide turning into an alcohol. The resulting structure is Ph-CH(OH)-CH3, a secondary alcohol with a phenyl group and a methyl group attached to the same carbon. This is named 1-phenyl-2-propanol. The product is not benzyl alcohol (Ph-CH2OH) because the Grignard adds a carbon and forms a new C–C bond, and not all the way reduced to a primary alcohol.

Grignard reagents add to carbonyl compounds to form alcohols after acidic workup, with the group from the Grignard becoming a new substituent on the carbon that bears the OH. Here, a methyl Grignard adds to benzaldehyde (Ph-CHO). The carbonyl carbon receives the methyl group, and after hydrolysis the oxygen is protonated to give an alkoxide turning into an alcohol. The resulting structure is Ph-CH(OH)-CH3, a secondary alcohol with a phenyl group and a methyl group attached to the same carbon. This is named 1-phenyl-2-propanol. The product is not benzyl alcohol (Ph-CH2OH) because the Grignard adds a carbon and forms a new C–C bond, and not all the way reduced to a primary alcohol.

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