Grignard reaction product involving a ketone

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The discussion revolves around the Grignard reaction involving a ketone, where the expected product is an alcohol. The initial attempt produced a compound identified as 3-phenyl-3-pentanol, but the actual outcome was an alkene instead. Clarification is sought on why the reaction led to an alkene and the role of sulfuric acid in this process. It is noted that the dehydration step, facilitated by sulfuric acid, results in the formation of the alkene. Understanding the mechanism and the conditions under which dehydration occurs is crucial for grasping the reaction's outcome.
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Homework Statement



Basically I have to show the product of this reaction:

Question.PNG




Homework Equations



Grignard reaction mechanism:
The conversion of a ketone to an alcohol

The Attempt at a Solution



My attempt of this reaction produces an alcohol with two ethyl groups attached to the central carbon as well as a phenyl group and an OH group attached to the central carbon, so the IUPAC name would be 3-phenyl-3-pentanol.

However, the answer is:
answer.PNG


Can someone please explain why the reaction produced an alkene instead of an alcohol. I do not know why this occurred and need some clarification. Also, when does this extra step occur.

Thanks.
 
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Think a little about step 3.
 
What occurs is step 3? I know that the H2SO4 is deprotonated to become HSO4. This produces the alcohol part of the compound, which is what I got. I am going to assume that deprotonation of HSO4 occurs, thus producing water and the alkene as shown in the answer. Is this right?
 
Look up "dehydration". Sulfuric acid is a powerful dessicant.
 
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