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Topic: Reversible ozonolysis  (Read 11028 times)

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Offline optimusprime

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Reversible ozonolysis
« on: February 10, 2008, 04:46:33 PM »
What do you say, is ozonolysis reversible?  That is, from two carbonyls can you form an alkene and Ozone?

Offline macman104

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Re: Reversible ozonolysis
« Reply #1 on: February 10, 2008, 05:13:56 PM »
I don't believe ozonolysis is reversible...but that's more a guess than anything.

Offline optimusprime

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Re: Reversible ozonolysis
« Reply #2 on: February 10, 2008, 05:32:00 PM »
It was a fevered dream more than anything.

Offline movies

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Re: Reversible ozonolysis
« Reply #3 on: February 10, 2008, 05:33:51 PM »
Well, you can do the reverse transformation, but it doesn't make ozone.

The reaction is called a pinacol coupling, sometimes also called an acyloin coupling or a McMurry coupling.  Messy reactions though.

Offline sjb

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Re: Reversible ozonolysis
« Reply #4 on: February 11, 2008, 02:38:25 PM »
Well, you can do the reverse transformation, but it doesn't make ozone.

The reaction is called a pinacol coupling, sometimes also called an acyloin coupling or a McMurry coupling.  Messy reactions though.

I thought a pinacol was 2 x carbonyl -> diol, and similarly acyloin 2 x carbonyl -> hydroxy carbonyl ?

Agreed though, these can be fairly messy

S

Offline movies

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Re: Reversible ozonolysis
« Reply #5 on: February 11, 2008, 10:54:26 PM »
True, I guess the pinacol part isn't the whole transformation, but it does make the C-C bond.  Then you can take the diol to an olefin by Corey-Winter reaction or something.

Offline zeoblade

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Re: Reversible ozonolysis
« Reply #6 on: May 27, 2011, 09:12:51 PM »
I'm sorry to dig up an old thread but I feel its really relevant.

I understand Ozonolysis can clean an alkene into 2 ketones but what if I wanted to do the reverse?

If I had 2 ketones, how can I do reverse ozonolysis to make and alkene without being messy and in good yield? For example, if I wanted to join 2 molecules of cyclohexanone?


Offline nox

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Re: Reversible ozonolysis
« Reply #7 on: May 28, 2011, 01:39:19 AM »
McMurry coupling

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