[sharbeldam]

I have been thinking about this for 4 hours.
My only attempt is adding a strong base to deprotonate, but then i can only add R group or do decarboxylation.
I cant add a halogen and eliminate it i would guess....
so what i do? :/

[rolnor]

You can use benzeneselenylchloride/Base first then oxidize to the selene oxide with H2O2 and this eliminates spontaneously . not sure what base is good, TEA? Its a very acidic position https://en.wikipedia.org/wiki/Selenoxide_elimination#:~:text=Elimination%20of%20selenoxides%20takes%20place%20through%20an%20intramolecular,-selective%20when%20acyclic%20%CE%B1-phenylseleno%20carbonyl%20compounds%20are%20employed.

[Vidya]

You can do alpha halogenation I think.
Remove acidic alpha H(to ketone and ester) using a base and add H2O with Br2 .
Remove Br by dehydrohalogenation process.

[sharbeldam]

The water would hydrolize the ester i think
and thanks rolnor, i read that way, i was thinking something o-chem 1/2 related and they dont teach that way

[Vidya]

Ester group can be added again.