Filemon
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hydrolysis amine of a keto-alpha amine
May it hydrolyze a amine of a keto-alpha amine with heated in strong aqueous acid?
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grind
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Do you mean R-CO-CH2-NR´R´´? You can´t hydrolyze that. By the way, it´s called amino ketone.
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Nicodem
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In molecules that have no hydrolysable bonds, no hydrolysis can occur.
Filemon, are alpha-aminoketones really what you are talking about? I'm unsure if Grind guessed correctly. Why don't you use a rational formula for
better understanding.
alpha-Aminoketones only get protonated in acidic aqueous media. Heating such solution would probably result in some decomposition, but since there is
nothing to hydrolyze no hydrolysis can occur. Many alpha-aminoketones are also fairly unstable as free bases so they are generally prepared as their
salts (hydrochlorides etc.).
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unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
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Filemon
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This molecule: amino-acetone => 2-hydroxy-propanal
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Nicodem
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That would require the aminoacetone to enolize to the side of the amino group, the so formed enamine (H<sub>2</sub>N-CH=C(OH)-Me) would
have to tautomerize to the imine (HN=CH-CH(OH)-Me) and this finally hydrolyze. As you see there are several steps before you get to a compound that
has a hydrolysable bond and all these steps are highly reversible. Furthermore, under acidic conditions the aminoketone is protonated and this
inhibits some of the steps even though it promotes the enolization (but I don’t know to which side!), so it is a matter of what is more influential.
Too harsh acidic conditions are also detrimental to the end product. Most such aldehydes are not particularly stable in highly acidic media and this
one in particular can also easily convert to hydroxyacetone.
I know of no example in the literature of this particular reaction. Essentially, what you are proposing is a reversal of the Amadori rearrangement. I could only find one such example and it is catalyzed with a mild base. It is the conversion of cathinone and its
N-methyl derivative to 1-phenyl-1-hydroxyacetone using aqueous sodium acetate:
Optically active phenylpropanolamine derivatives. VIII. Preparation of dimeric ethers of phenylpropanolamines.
Takamatsu, Hideji.
Yakugaku Zasshi, 76 (1956) 1241-1243.
Unfortunately the abstract (Chem. Abs. 51:21611) says nothing about it and only Beilstein refers to this paper as describing the above
mentioned reaction. So it would be necessary to check the paper, but I do not have access to Journal of Pharmaceutical Society of Japan (Yakugaku
Zasshi). So, even though Beilstein mentions this reaction, I’m still very skeptical as it might be an abstraction error, especially if
considering that these aminoketones self condense in basic media and get oxidized to substituted pyrazines.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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MagicJigPipe
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Surely there must be easier ways to lactaldehyde. Apparently it is normally produced from 1,3-propanediol via fermentation with a certain bacteria
(for some reason my computer is screwed and I can't view the page that says this, sorry).
What reaction will you be using the it for?
"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any
question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and
that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think,
free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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solo
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Optically active phenylpropanolamine derivatives. VIII. Preparation of dimeric ethers of phenylpropanolamines.
Takamatsu, Hideji.
Yakugaku Zasshi, 76 (1956) 1241-1243.
............unfortunately the publisher only has these archived issues but doesn't include the issue needed,
YAKUGAKU ZASSHI
Vol.86-105 No.1-12
Vol.106 No.1,11,12
Vol.107-120 No.1-12
..........source,
http://www.journalarchive.jst.go.jp/english/jnltop_en.php?cd...
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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