Organic Research Project

[Jeremiah23]

Hi. I am currently doing a research project on synthesizing a water-soluble rotaxane via Diels-Alders reaction. But I am facing a problem in synthesizing this molecule(please refer to attached photo) which is part of the process to synthesize a dienophile for Diels-Alder reaction. I anticipated to be able to synthesize compound 17 from compound 16 via hydrolysis of the methoxycarbonyl group, but it went unsuccessful. I think instead of the methoxycarbonyl group, the maleimide group underwent hydrolysis. Are there any ways to resolve this issue? How can I hydrolyze the methoxycarbonyl group under the presence of maleimide? 

[hypervalent_iodine]

I’d say your main problem is that you can’t hydrolyse the ester with an alkoxide like that.

You need a hydroxide, or you need to do it under acidic conditions. 

[Jeremiah23]

1 hour ago, hypervalent_iodine said:

I’d say your main problem is that you can’t hydrolyse the ester with an alkoxide like that.

You need a hydroxide, or you need to do it under acidic conditions. 

I really appreciate your reply. Why can’t this reaction be done in basic condition? I’m still not very clear in your statement. 

[hypervalent_iodine]

I didn’t say that. I said it can’t be done with an alkoxide. If you do the arrow pushing on the scheme you drew you should hopefully be able to see why it would never work.

I also went on to say that in order to do the reaction you need hydroxide or some other aqueous base, but you can also use acid. I think hydroxide base would work fine, however. 

[chenbeier]

In alcaline conditions also the imid group will be destroyed.

[hypervalent_iodine]

4 hours ago, chenbeier said:

In alcaline conditions also the imid group will be destroyed.

Not necessarily; with careful addition and control of equivalents I should think the esters would hydrolyse over the imide. A carbonate base may also do the trick.