[vhpk]

Hi everyone,
I've got a question related to the acetal formation.
I'm asked to draw the mechanism for this reaction:

I know how to draw the mechanism for an acetal formation. However, in this case, I don't know what to do with the double bond since the mechanism has nothing to do with the double bond. Why does it shift ? I also try the conjugation addition way but still get nothing positive.
Any help would be highly appreciated Thank you

[sHaY]

maybe it's some sort of a typo?

[orgopete]

I'm sure the structure is correct. Try drawing an acid catalyzed enolization reaction.

[vhpk]

Thank you orgopete,
Here is my trial, is it correct ?

the next step is just acetal formation

[orgopete]

That would do it (ignoring the error in 3 to 4). You could also start the ketalization at the protonated ketone (4). It might make some sense to understand the deconjugation process if protonation of 3 might be more favorable in the ketalization process than protonation of 1. 

[vhpk]

Thanks a lot orgopete