Grignard reaction of acetone with methylmagnesium bromide yields after hydrolysis?

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Grignard reaction of acetone with methylmagnesium bromide yields after hydrolysis?

Grignard reagents act as nucleophiles and add the R group from the Grignard to the carbonyl carbon, with the oxygen becoming an alkoxide that is later protonated to give an alcohol. Here, a methyl group from methylmagnesium bromide attacks the carbonyl carbon of acetone (which bears two methyl groups), forming a tertiary alkoxide attached to MgBr: (CH3)3C–O–MgBr. After hydrolysis, this alkoxide is converted to tert-butanol, so the product is tert-butanol. The other options don’t fit this carbon skeleton: the reaction with a ketone like acetone and a methyl Grignard directly yields a tertiary alcohol with three methyl groups on the same carbon, which is tert-butanol.

Grignard reagents act as nucleophiles and add the R group from the Grignard to the carbonyl carbon, with the oxygen becoming an alkoxide that is later protonated to give an alcohol. Here, a methyl group from methylmagnesium bromide attacks the carbonyl carbon of acetone (which bears two methyl groups), forming a tertiary alkoxide attached to MgBr: (CH3)3C–O–MgBr. After hydrolysis, this alkoxide is converted to tert-butanol, so the product is tert-butanol. The other options don’t fit this carbon skeleton: the reaction with a ketone like acetone and a methyl Grignard directly yields a tertiary alcohol with three methyl groups on the same carbon, which is tert-butanol.

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