[OhMyGod]

Hi dudes, just wana know whether what product i would get when i reduce this compound (CH3CH=CHCOOH, basically consists of C=C(alkene) and -COOH functional group) using H2 gas + nickel catalyst + 200degreescelsius ..  My guess is CH3CH2CH2COOH. but im nt sure whether -COOH would undergo reduction in such conditions.


So, I just wana know whether H2 gas + nickel catalyst + 200C as conditions and reagents would reduce -COOH to -COH aldehyde group? I know these conditions are not strong enough to reduce it back to alcohol function group, but im nt sure with aldehyde.

Rgds.

Thanks.

[lemonoman]

Google:   Reduce carboxylic acid +hydrogen +Nickel

The first link gives us this:

"platinum, palladium, nickel" ... "serve as catalysts for reactions of dihydrogen. Typically dihydrogen adds to multiple bonds - alkenes, alkynes, carbonyl compounds - in the presence of these catalysts. Since the hydrogenation reaction takes place on the surface, it is stereospecific syn."

[Yggdrasil]

I don't think a carboxylic acid to aldehyde reduction will happen.  Aldehydes are pretty sensitive to reduction so almost anything that will reduces a carboxylic acid takes it all the way to an alcohol.

[Doc_1998]

Metal-H2 reduction reduces olefinic and acetylenic bonds only.

[kiwi]

Metal-H2 reduction reduces olefinic and acetylenic bonds only.

Not entirely true, it depends on the metal. Nickel (especially activated stuff like Raney) will reduce dithioacetals back to methylenes, platinum and palladium will cleave certain susceptible C-Heteroatom bonds, as well as various heteroatom-heteroatom bonds. And a bunch of other things like reduction of imines also occur. But normal esters are stable to pretty forcing lab-level conditions (high surface area Pt, 4 atm H2), and nickel is a less reactive catalyst than platinum, so i'd wager you should be fine.