Mechanism for the conversion of an unsaturated alkyl halide to an alcohol

**Question:**



> 
> Predict the mechanism for the following reaction:
> 
> 
> [![conversion of an unsaturated alkyl halide to an alcohol](https://i.stack.imgur.com/9crNG.png)](https://i.stack.imgur.com/9crNG.png)
> 
> 
> 


**Attempt:**


I thought it will proceed through SN1 mechanism as $\ce{H\_2O}$ is involved (solvolysis). So I proceeded with the formation of a primary carbocation, which then rearranges via 1,2 methyl shift. Then the nucleophilic attack of $\ce{OH^{-}}$ leads to the following product, which is different form the required one.


Can any further steps lead to the required product or am I wrong from the start (most probably)?


![enter image description here](https://i.stack.imgur.com/dk5tK.jpg)




For what it's worth, this reaction does not appear in the literature. So, whether it actually forms the product or not is anybody's guess.


However, if I had to suggest a mechanism... I would note first that an SN1 reaction on a primary centre, as you have proposed, is difficult. I think it more likely that the alkene assists in the expulsion of the chloride.


[![Loss of chloride](https://i.stack.imgur.com/ieBRY.png)](https://i.stack.imgur.com/ieBRY.png)


The resulting cyclopropylmethyl carbocation is [stabilised](https://chemistry.stackexchange.com/q/19090/16683) and is electrophilic at multiple sites. I have only drawn one resonance form, but there are a few more. Attack of water at the tertiary carbon leads to the desired product after deprotonation.


[![Formation of desired product](https://i.stack.imgur.com/qR6LU.png)](https://i.stack.imgur.com/qR6LU.png)


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