How does alkene+carboxylic acid=ester

[MyRealNameIs]

Hi

I am doing Collins practice problem

The question is ethene + carboxylic acid + H+ -> ester

No explanation

I tried searching the web but couldn't find a mechanism

How does ethene attack in a way that it forms a ester?

I thought the double bond of the ethene would attack the alpha carbon and the OH will be released, forming a ketone with H2O.

Thanks

 

[Biochemistry2014]

This looks similar to a reaction of ethene hydration. Perhaps a proton is released from the carboxylic acid and is grabbed by the pi electrons of ethene.

You now have a carbocation: CH3CH2+

Now this carbocation is susceptible to attack from the lone pair of the carboxylate anion, forming an ester.

That would be my best interpretation of a potential mechanism.