Help with Grignard Reactions: I'm Stuck!

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The discussion focuses on understanding Grignard reactions, specifically the transformation of carbonyl groups. It emphasizes that the double bond oxygen converts to a single bond oxygen-hydrogen during the reaction. Participants stress the importance of not just memorizing reactions but understanding the underlying mechanisms, including drawing electron-pushing diagrams and identifying intermediates. The initial step involves nucleophilic addition of the Grignard reagent to the electrophilic carbon of the carbonyl, leading to a tetrahedral intermediate. Ultimately, the reaction results in the formation of a secondary alcohol after acid work-up.
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I need help with the reaction.

I know the double bond O goes to single bond O-H

I'm not sure what else to do.

Thanks
 

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You're doing O. Chem wrong. Don't *memorize* the net result of a transformation, or you'll just memorize thousands and thousands of reactions. It's like physics: don't memorize the net equation of all the forces acting on a body for every situation, know how to derive them!

Approach this problem step by step, draw the electron-pushing and the intermediates/transition states, or you will be hopelessly lost.

Grignard Reagents are effectively "R-" or nucleophilic alkyl chains. You have an electrophilic carbon here (i.e., carbonyl C), so the first stop is going to be a nucleophilic addition to the carbonyl to form a tetrahedral intermediate, stabilized by MgX cation. Acid work-up will produce a secondary alcohol (since you're starting with an aldehyde).
 
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