Warum lassen sich tertiäre Alkohol nicht mehr so leicht weiter oxidieren (z.B. Citrat)? Der Strich zum COO- könnte doch einfach umgelagert werden wenn COO-?
wenn COO- abgespalten wird?
Also ich versteh’s so beim oxidieren eines sekundären Alkohols, dass zwei Wasserstoffatome gehen, sich abspalten und man daher eine Doppelbindung von Kohlenstoff und Sauerstoff erreicht. Wie bei 2-Propanol.
Wieso geht das bei Citrat nicht?
Man hat da an dem C-Atom wo das OH dranhängt zwar kein weiteres H-Atom mehr, aber man hat doch COO-
Wenn ich das COO- abspalte, dann kann ich doch einfach eine Doppelbindung zum C hinbekommen wenn das H-Atom am C auch abgespalten wird wie das COO-
In meinem Buch steht halt:
“Tertiäre Alkohole lassen sich nicht einfach so weiter oxidieren, da es kein freies Wasserstoffatom mehr gibt, das bei der Oxidation entfernt werden könnte”
Ja na und? Wieso kann man nicht das COO- analog zum H entfernen?
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There are reactions in which CO2 is split off and the OH group is oxidized to the keto group. But for this, of course, a C-C bond must always be cleaved, otherwise five-binding carbon is obtained.
Never heard of five-binding carbon. He wants 4 electrons and not 5.
Where’s the problem? Then you split the COOH so you get the keto group?
Then the statement “Tertiary alcohols cannot simply be oxidized further as there is no free hydrogen atom that could be removed during the oxidation” is not you from my book?
Why don’t you split hydrogen or the COOH?
This is a special case because relatively stable carbon dioxide is formed in the reaction. In the case of tertiary alcohols, one usually means such as tert-butanol. Three alkyl groups or other hydrocarbon chains depend on the tertiary carbon atom. It cannot be “separated” by oxidation without letting the whole residue of the molecule also react to carbon dioxide and water.
If you remove the COO^- you remove one of the carbon atoms that make up the tertiary alcohol.
Go, of course, but come out to the same thing as if you first make a secondary alcohol from the tertiary alcohol.
What would it look like if you make a secondary from the tertiary alcohol?
In the above example. Where’s the problem? You can split off -COOH and oxidize the C and get a keto group? Where is the problem
Understand the statement “Tertiary alcohols cannot simply be oxidized as there is no free hydrogen atom that could be removed during oxidation” in my book.
Because it doesn’t matter if there is no hydrogen atom
The –COOH is then split off and finished and the carbon atom can oxidize and get a keto group. No hydrogen has to be there.
Whether you split off the carboxylic acid group or one of the other radicals plays no (essential) role for this.
What I forget: hydrogen atoms are very small, at such a point another molecule/atom/ion can attack comparatively easily.
Assembled “residues” are quite bulky, another molecule/atom/ion only comes to the “surface” of the “residue”, but only very, very difficult at the rest past the place where the rest is bound to the main chain.