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Topic: Question about methanolysis mechanism of furan ring  (Read 2886 times)

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Offline OrganicH2O

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Question about methanolysis mechanism of furan ring
« on: January 15, 2018, 06:28:52 PM »
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/1OyL2

A 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...
« Last Edit: May 18, 2018, 05:22:51 PM by Arkcon »
I have a Master's in organic chemistry and I am exposed to a LOT of different introductory organic chem classes in the course of my work, ranging from very basic to Harvard. I am here to refine my knowledge and consult with other organic chemistry nerds.

Offline OrganicH2O

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Re: Question about methanolysis mechanism of furan ring
« Reply #1 on: January 26, 2018, 05:31:14 PM »
So nobody has an idea? It's driving me crazy. I know the book has some typos but I checked the website and it is not listed as a typo...I would even appreciate confirmation from a chemist who tried it and could not figure it out.
I have a Master's in organic chemistry and I am exposed to a LOT of different introductory organic chem classes in the course of my work, ranging from very basic to Harvard. I am here to refine my knowledge and consult with other organic chemistry nerds.

Offline Arkcon

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Re: Question about methanolysis mechanism of furan ring
« Reply #2 on: May 18, 2018, 05:23:33 PM »
Did you ever get to the bottom of this one, OrganicH2O:?
Hey, I'm not judging.  I just like to shoot straight.  I'm a man of science.

Offline OrganicH2O

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Re: Question about methanolysis mechanism of furan ring
« Reply #3 on: May 18, 2018, 06:58:04 PM »
Sadly I did not. I gave up a while ago.
I have a Master's in organic chemistry and I am exposed to a LOT of different introductory organic chem classes in the course of my work, ranging from very basic to Harvard. I am here to refine my knowledge and consult with other organic chemistry nerds.

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