Synthesis of 2-benzylcyclohexan-1-ol from cyclohexanone

There are no conditions given and a mechanism is required.


I first thought it could be along the lines of Claisen rearrangement but that needs an aromatic ring. Since the Claisen rearrangement can't be used I considered a ($\mathrm{S\_N2}$) reaction of benzyl bromide by the alpha carbon followed by reduction of the carbonyl.


[![enter image description here](https://i.stack.imgur.com/m8Anb.png)](https://i.stack.imgur.com/m8Anb.png)




Making a carbon-carbon bond at the alpha position of a carbonyl suggests using some kind of enolate chemistry. In contrast to an SN2 type reaction with an alkyl halide (which can give over-alkylation and competitive O-alkylation), an aldol condensation is a reliable way to construct the requisite C-C bond. Here cyclohexanone reacted with benzaldehyde under basic conditions gives an enone. Two subsequent reduction steps, hydrogenation followed by hydride addition to the ketone, give the target compound.


[![enter image description here](https://i.stack.imgur.com/RNg4Q.png)](https://i.stack.imgur.com/RNg4Q.png)


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[![Mechanism of synthesis](https://i.stack.imgur.com/cjtdw.png)](https://i.stack.imgur.com/cjtdw.png)


Ok so I found an answer:


* Deprotonate at the alpha carbon using LDA which gives a negative charge.
* This then attacks $\ce{BrCH2Ph}$ at the $\ce{CH2}$ and kicks off the bromine in the process ($\mathrm{S\_N2}$).
* Then to form the alcohol the ketone is reduced using $\ce{LiAlH4}$ using THF as a solvent.


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