sergide
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What is the simplest way to reduce a carboxyl group?
What is the simplest way to reduce a carboxyl group (R-COOH) to a methyl group (R-CH3)?
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DJF90
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I dont think there is a direct method for that transformation. I can readily think of a 2-step procedures, and its likley others would come if I
thought about it more:
Reduce with DIBAH, then perform a wolff-kishner/clemmensen/mozingo
Using the humsdeicker followed by formation of grignard and hydrolysis would work, albeit a loss of a carbon atom also, i.e. RCOOH -> RH
A longer but suitable route would be reduction with Ca(BH4)2, followed by tosylation and reduction with NaBH4 or LAH. A better alternative to LAH
could be LiBH(Et)3.
[Edited on 17-8-2009 by DJF90]
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solo
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........use the search engine here as the topic has been discussed at lenght.........solo
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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JohnWW
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If you want to do that on an industrial scale, instead of those costly hydride reagents, it would be more economical to reduce carboxylic acids to
methylated hydrocarbons with H2 gas under heat and pressure using Ni or Pd as a catalyst.
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sergide
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Alright, thanks a lot.
Also, what about if like I were to change that -OH to a -Cl using phosphourous trichloride or something and then just use a hydride to reduce both the
-Cl and =O? Would that give R-CH3?
edit: actually nevermind there's a lot of literature on this i'll just check that
[Edited on 18-8-2009 by sergide]
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