I recently ordered an array of C-3 to C-8 primary alcohols and carboxylic acids with the intention of making an array of esters via fisher
esterification. I've been having a lot of fun so far with all the different smells and their various properties (I'll probably spend some time on a
thorough write-up documenting some of the challenges and quirks I've inevitably run into once I have a few more in my collection, there's definitely
not a one size fits all reaction setup for these things), but when preparing to make octyl acetate I realized that the company accidentally sent me
octanAL instead of the octanOL I ordered.
Of course I could very easily order some proper octanol and go from there, but my first thought was to just try and reduce it myself for the fun of
it! The only issue is that every source I find requires what are for me very exotic reducing agents like LAH, sodium borohydride, or Pd/C (I know H2
does the reducing but the catalyst is still expensive!)
So my question is, are there any relatively amateur friendly reactions that could do the same? I could swear I read about some reduction method for
aldehydes using zinc or magnesium forever ago, but I haven't yet been able to find it again (assuming I'm not just crazy). And if not, is there
anything interesting I could use my octanal for anyway, maybe to make some other pleasant smelling compounds? Thanks! bnull - 6-9-2024 at 06:44
You may try your hand at electrolytic reduction. There's a book by Walter Löb about it in the Library; some 90 years old but still interesting and can give you the gist of the process. There are other books but that one was the first I ever
read on the subject.
They sending -al in place of -ol is quite funny.Dr.Bob - 6-9-2024 at 06:56
Roughly where are you located? US, Europe or elsewhere? NaBH4 is the simplest way, that is not nearly as bad as LAH or such.
If you had a source of H2, the amount of Pd/C you need would be tiny. That might be easy to find a sample of in some places.SaccharinSlayer157 - 7-9-2024 at 13:41
Quote:
Here's something you can try, essentially amateur-friendly: S. Velázquez-Olvera et al., A Convenient Electrolytic Process for the Reduction of
Aldehydes.
This is exactly the kind of thing I was hoping for, how cool! I've read about electrolytic reductions in passing before but never saw anything this
approachable.
Quote:
Roughly where are you located?
I'm in the southern US, the cheapest I could find was 10g for $30 on ebay. Come to think of it, that about as much as a new bottle on octanol would
cost anyway, my only worry is that I don't really have the glassware or vacuum pump necessary to safely flush my apparatus beforehand and avoid a
fire. I'm not sure how strictly necessary that procedure is, but the last thing I need is another explosion!bnull - 7-9-2024 at 14:44
Quote:
I've read about electrolytic reductions in passing before but never saw anything this approachable.
This one is a review: Frank D. Popp, Harry P. Schultz, Electrolytic Reduction of Organic Compounds, https://pubs.acs.org/doi/10.1021/cr60215a002. It's 43 years old and, while not the state-of-the-art, is quite good.jackchem2001 - 7-9-2024 at 20:23
I was under the impression that Pd/C (and other metals) catalyzed hydrogenation generally do not reduce carbonyl groups. Anyways, I think a formic
acid or sodium in ethanol reductions may be accessible.
