Grignard reagent methylmagnesium bromide added to benzaldehyde gives which alcohol after workup?

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Grignard reagent methylmagnesium bromide added to benzaldehyde gives which alcohol after workup?

Grignard reagents add as carbon nucleophiles to carbonyl compounds and, after acidic workup, form alcohols. Here, methylmagnesium bromide (CH3MgBr) attacks the carbonyl carbon of benzaldehyde (Ph-CHO). The CH3 group attaches to that carbon, pushing electrons onto the oxygen to form an alkoxide coordinated to MgBr. After hydrolysis, the alkoxide is protonated to give a secondary alcohol with the carbon bearing the OH attached to both a phenyl group and a methyl group. That gives Ph-CH(OH)-CH3, i.e., 1-phenyl-2-propanol. This is a secondary alcohol because the carbon bearing the OH is connected to two carbon-containing groups (phenyl and methyl).

Grignard reagents add as carbon nucleophiles to carbonyl compounds and, after acidic workup, form alcohols. Here, methylmagnesium bromide (CH3MgBr) attacks the carbonyl carbon of benzaldehyde (Ph-CHO). The CH3 group attaches to that carbon, pushing electrons onto the oxygen to form an alkoxide coordinated to MgBr. After hydrolysis, the alkoxide is protonated to give a secondary alcohol with the carbon bearing the OH attached to both a phenyl group and a methyl group. That gives Ph-CH(OH)-CH3, i.e., 1-phenyl-2-propanol. This is a secondary alcohol because the carbon bearing the OH is connected to two carbon-containing groups (phenyl and methyl).

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