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First published direct reduction of COOH to CH3

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Rhodium:
I can think of the use of this in the reduction of phenylalanine to amphetamine, and reduction of tryptophan to AMT.

A Direct Reduction of Aliphatic Aldehyde, Acyl Chloride, Ester, and Carboxylic Functions into a Methyl Group
Gevorgyan, V.; Rubin, M.; Liu, J.-X.; Yamamoto, Y.
Journal of Organic Chemistry 66, 1672-1675 (2001) (https://www.thevespiary.org/rhodium/Rhodium/pdf/carboxylic2methyl.pdf)
DOI:10.1021/jo001258a

Abstract
Aliphatic carboxyl groups was efficiently reduced to the methyl group by triethylsilane in the presence of a catalytic amount (5 mol%) of the non-traditional lewis acid B(C6F5)3. To the best of our knowledge, this is the first example of exhaustive reduction of an aliphatic carboxyl function to a methyl group. Aliphatic aldehydes, acid chlorides and acid anhydrides also underwent complete reduction under similar reaction conditions.

All yields from all the published substrates range between 91 and 99%.

Experimental conditions:

Triethylsilane (30 mmol) was added under an argon atmosphere to a mixture of the carboxylic acid (5 mmol) and B(C6F5)3 (0.25 mmol) in 5 ml DCM. The mixture was stirred at RT for 20h, the reaction quenched (Et3N, 0.25 ml), filtered through Celite and concentrated. The residue was mixed with 40% HF (5-7 ml) in ethanol (30 ml) and refluxed for 7h. Water (60 ml) was added, the product extracted with 3x30ml pentane, The extracts washed with water, dried over MgSO4 and the solvent and Et3SiH was removed under vacuum. The residue was purified by flash column chromatography on silica gel to afford the products in 91-99% yield.

halfapint:
Would that Lewis acid bee pronounced tri-perfluorophenyl borane? Don't have any on me right now. (Wouldn't ever care to get any on me, come to that...) Non-traditional, well I can believe that.

Chemistry is a science in which the "impossible" is continually happening. As long as it is thermodynamically allowed, somebody is always going to find a new way to produce some reaction, which had previously been ruled out. These new developments, I'm sure, are always surprising to those well versed in the field. Keep on finding 'em, Rhodium.

Turning science fact into <<science fiction>>

foxy2:
That triethyl silane could be some useful shit.
Time to pick up a few kilos before its watched
Post 191102 (missing) (Twist: "Re: Pulling Caffine", Stimulants)


Do Your Part To Win The War

Rhodium:
Too bad 100g of the stuff costs $150 (Aldrich).

http://rhodium.lycaeum.org

Osmium:
Meaning the actual value is more like 7.50-15$/100g  ;)

I better not ask how much the perfluorotriphenylborane costs...

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