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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: athermic on February 22, 2008, 05:11:13 PM

Title: Suzuki coupling with an acyl halide?
Post by: athermic on February 22, 2008, 05:11:13 PM

Hi,

I realize that there likely are much better ways to accomplish this particular synthesis, however I was just curious as to whether this coupling reaction would be possible and if so the types of yields I would obtain:
(https://www.chemicalforums.com/proxy.php?request=http%3A%2F%2Fimg148.imageshack.us%2Fimg148%2F7848%2Frxncv1.th.png&hash=1daac17844684a5897ab4a3b299a180ab19cad6f) (http://img148.imageshack.us/my.php?image=rxncv1.png)

Background: I'm trying to do a retrosynthesis (theoretical) from benzaldehyde to this compound:
(https://www.chemicalforums.com/proxy.php?request=http%3A%2F%2Fimg297.imageshack.us%2Fimg297%2F6972%2F85129481up9.png&hash=7a3f589ef766b64d8d32428407f937d47c0f92d3)

I oxidized the aldehyde to an acid using sodium dichromate/acid+heat, and activated the carboxylic acid using thionyl chloride/heat.

I think that the Suzuki-style reaction would probably not proceed as planned due to the carbonyl changing the reactivity of the benzyl position significantly.  However, I'm not sure.

I would greatly appreciate any thoughts.

Thanks in advance!
 

Title: Re: Suzuki coupling with an acyl halide?
Post by: agrobert on February 22, 2008, 05:46:51 PM

I don't think this would work.  Also, if you think it is not the best way why would you try it?  What other reactions do you know of that are much better suited for this reaction.  Aldol? Benzaldehyde + Acetophenone --> -->

Title: Re: Suzuki coupling with an acyl halide?
Post by: agrobert on February 22, 2008, 06:44:49 PM

I take that back.  It will work I just don't see the practicality in this instance.  Here is a reference for chalcone synthesis.

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6THS-48V6XXS-1X&_user=4429&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000059602&_version=1&_urlVersion=0&_userid=4429&md5=a5391f5129653438861f5b854e8624f8

Title: Re: Suzuki coupling with an acyl halide?
Post by: athermic on February 22, 2008, 07:52:54 PM

Thanks for the reply and the link!  The reason I posted the question was because this retrosynthesis was part of an assignment that I had already turned in and was presenting to my professor.  He told me that he didn't believe the reaction would work, but if I could find and document evidence of my reaction yielding the product before Monday, he would accept my answer.

Aldol condensation would probably be more effective in the real world.

Thanks once again!

Title: Re: Suzuki coupling with an acyl halide?
Post by: agrobert on February 22, 2008, 08:01:07 PM

Yea actually the yields in the paper aren't bad but Suzuki coupling reactions conditions are difficult to maintain.  Acyl halides are very reactive and would require extremely anhydrous conditions.  This problem just screams Aldol but its good you reasoned that a Suzuki reaction could work as well. ;)