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Chemistry Forums for Students => Organic Chemistry Forum => Organic Chemistry Forum for Graduate Students and Professionals => Topic started by: strigoi on January 02, 2022, 06:59:33 AM

Title: Hosomi-Sakurai experiences
Post by: strigoi on January 02, 2022, 06:59:33 AM
Hey,

Have anybody ever used Hosomi-Sakurai rxn? I'm wondering that could it be done on a,b-unsat. ester as opposed to a,b-unsat. ketone? I cannot find any literature on this rxn with esters, only one with ketoesters but that is not exactly what im looking for.
Title: Re: Hosomi-Sakurai experiences
Post by: rolnor on January 02, 2022, 08:30:56 AM
What product do you want? I dont think a ester is reactive enough and the product would be a ketone or?

https://en.m.wikipedia.org/wiki/Sakurai_reaction
Title: Re: Hosomi-Sakurai experiences
Post by: strigoi on January 02, 2022, 11:13:47 AM
Hey,

This is my starting material. Just trying to figure out something other than just organocuprate additions, so I tried to search Hosomi-Sakurai for esters.

Honestly, any conjugate addition to a,b-unsat. ester seems to be rare, let alone on a four membered ring. There is hardly anything on this topic. Would it be worth a shot, or is the reason for lack of literature that it just isnt working?
Title: Re: Hosomi-Sakurai experiences
Post by: rolnor on January 02, 2022, 12:31:38 PM
Thats interesting. Hard to say if the fourmembered ring makes it harder. It looks like a good case for organocuprate. Its not surprising you dont find anything in the literature, have you made a reaction-substructure search in Scifinder and/or Reaxys?
Title: Re: Hosomi-Sakurai experiences
Post by: rolnor on January 02, 2022, 12:38:23 PM
Maybe if you want to try something exotic you could use copper fluoride instead if the titanium chloride and generate a cuprate in situ, I would try sonication in THF.
Title: Re: Hosomi-Sakurai experiences
Post by: wildfyr on January 02, 2022, 12:56:07 PM
Aren't strained cycloalkenes usually more reactive? In this case the reaction leads to lower ring strain so it should be enthalpically favorable, at least in that aspect.
Title: Re: Hosomi-Sakurai experiences
Post by: strigoi on January 02, 2022, 02:27:49 PM
Thats interesting. Hard to say if the fourmembered ring makes it harder. It looks like a good case for organocuprate. Its not surprising you dont find anything in the literature, have you made a reaction-substructure search in Scifinder and/or Reaxys?
Yes, i've tried to scour for options with reaxys. I will definitely try different setups with organocuprates, my professor was curious about the Sakurai case as well so he asked me to look it up.

Maybe if you want to try something exotic you could use copper fluoride instead if the titanium chloride and generate a cuprate in situ, I would try sonication in THF.

Thanks, I will consider this also!

Aren't strained cycloalkenes usually more reactive? In this case the reaction leads to lower ring strain so it should be enthalpically favorable, at least in that aspect.

Yeah, this is what im hoping.

Title: Re: Hosomi-Sakurai experiences
Post by: rolnor on January 03, 2022, 02:20:35 AM
Yes, a lot if strain in this small ring. Its a ambitious project, nice!