Hi, I was reading chapter 29 of Clayden/Warren/Greeves second edition and I came across a reaction on page 737 I do not understand completely.
Here is a link to the mechanism:
https://imgur.com/a/1OyL2A furan with an alpha beta unsaturated ester is opened up in methanol. The problem is, the only parts I am confident in lead to an acetal on one side instead of the methyl ester. Also, there is an alkene in the wrong place. The only way that I can see to make the product is to do a bizarre conjugate addition of hydride, provided by the acetal. Then the partial hydrolysis of an ortho ester leads to the product.
Is there a better way to do this? Anybody thought about this before?
P.S. I know I protonated Furan at the wrong position (should be 2 position) but that still doesn't solve the issue I'm having. I tried it that way also...