goldberg
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Hydrogenolysis of benzylic esters - looking for references
I came across mention that it is possible to replace hydroxyl group attached to benzylic carbon with hydrogen (ie. prepare ethylbenzene from
1-phenoxyethanol) by first preparing ester (say with acetic acid) and then hydrogenating this ester to hydrocarbon.
Unfortunately i only managed to find information about usage of benzylic esters and ethers as protecting groups and then removing them via
hydrogenation.
I also find a mention about removing whole ester group and getting alkane with electrolysis but again failed to find any references.
I am very curious about details, conditions and mechanism of this reaction but failed to find anything trustworthy. I looked for information about
hydrogenation and hydrolysis of benzylic esters on google scholar and other sites with scientific articles but without any succes.
I will be very graceful for any references and/or information (including practial things) about this reaction.
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Corrosive Joeseph
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I have told you already............ You NEED access to References forum........... 
PM admin. Username woelen............ Bert must be on his holidays
No one will do your research for you.
Also, you need a reference to post in 'Organic Chemistry'.
I'm not busting yer ass. Please be welcome.
/CJ
Being well adjusted to a sick society is no measure of one's mental health
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goldberg
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I just got this permission.
I would like to research it on my own, i just ask for some help.
I'm posting this questions in reference forum.
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Corrosive Joeseph
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Maybe a mod can move it for you.
Usually when you ask for references you need to know the citation.
After that it turns into Alice in wonderland and the rabbit hole.
You'll never know where you will end up
/CJ
Being well adjusted to a sick society is no measure of one's mental health
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zed
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Lots of ways to perform that reduction. Ester or not.
Commonplace is P/I2. Too easy, in fact. Caused both reagents to be "Listed".
Because of the stability, of what we used to call, the Benzyl-Carbonium ion, the -OH is easily displaced and/or reduced. Very handy.
https://pubs.acs.org/doi/abs/10.1021/jo2018087
There is also a reference to such a reduction, by hydrogenation, on page 65, of the April 2004, Microgram magazine. https://www.dea.gov/pr/micrograms/2004/mg0404.pdf
https://en.wikipedia.org/wiki/Carbenium_ion
[Edited on 3-8-2018 by zed]
[Edited on 3-8-2018 by zed]
[Edited on 4-8-2018 by zed]
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Loptr
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Whoa, whoa, now.... where did the benzylic hydroxyl go in this patent? N-formylephedrine reduced to N-formyldesoxyephedrine with just Raney nickel? I
thought you had to turn the hydroxyl group into a better leaving group.
https://patents.google.com/patent/US20080293971
I was trying to find a good reference for the reduction of benzylic acetates because I came across a good one recently. I am pretty sure it was with
Raney nickel.
[Edited on 4-8-2018 by Loptr]
[Edited on 4-8-2018 by Loptr]
[Edited on 4-8-2018 by Loptr]
"Question everything generally thought to be obvious." - Dieter Rams
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Corrosive Joeseph
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Me too.......... But apparently not..........
'Raney Ni catalyzed hydrogenolysis of Ephedrine amide to Desoxyephedrine amide'
http://www.sciencemadness.org/talk/viewthread.php?tid=5698
Here is the original thread -
https://chemistry.mdma.ch/hiveboard/crystal/000393077.html
/CJ
Being well adjusted to a sick society is no measure of one's mental health
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zed
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Umm. Somehow reminiscent of Alkylating Indoles, with Amido-Alcohols.
Newfangled kinda thinking. Easing the dis-location of the OH group, via the electron depleting effect of the adjacent -C=O(R) on the Amino function?
Enlighten me.
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