kamal
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Oxime Reduction
Hello friends ! ![;)](./images/smilies/wink.gif)
I'm trying reduction of a cyclo-aliphatic Oxime to its Amine. I performed reduction with sodium metal in different alcoholic solvents, but getting
only 50-55% yield. ![:(](./images/smilies/sad.gif)
Can you please suggest me some other process references for such OXIME REDUCTION using some other routes/commercial reagents with good yield ?
Awaiting your replies ! ![:D](./images/smilies/biggrin.gif)
Thanking you,
NK
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Sriraman
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Try Sodium and Liquid ammonia at -50 deg C or Sodium and alcohol. are u looking for stereospecifc reduction ?
Sriraman
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solo
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Stereochemical Studies in the Aminodesoxyinositol Series. rncso-Inosamine-2 and scy Zlo-Inosaminel
LAURENS ANDERSON AND HENRY A. LARDY
Journal of the American Chemical Society,1950 ,vol:72 iss:7 pg:3141
Excerp
.........Carter, et al., hydrogenated the phenylhydrazone
(IV, R = -NHCeH6) or oxime (IV, R = -OH)
of scyllo-meso-inosose in aqueous ammonia solution
over Raney nickel and obtained a mixture of
two primary amines. We found that when glacial
acetic acid was used as the solvent and Adam
platinum oxide as the catalyst, the primary
amine formed from either of these derivatives was
almost exclusively a single isomer. The compound
is identical with Carter’s “inosamine SA.”
Since the starting material was a keto-inositol
of known configuration,6d the only point requiring
clarification is the configuration of the amino
group. The steric selectivity of the conditions
employed by us for the synthesis of “inosamine-
SA” seems well enough established to permit us
to identify it as meso-inosamine-2 (11). If this
conclusion is correct, “inosamine SB” should be
scyllo-inosamine (111).
Since inosose derivatives are very alkali-labile,
it was not possible to carry out a reduction under
the best “trans-directing” conditions. However,
with sodium amalgam at PH 5.5-6.5 the “inosamine-
SB”” of Carter, et al., accounted for an
unexpectedly large proportion (73%) of the primary
amine formed. The fact that this isomer,
which occurs to a limited extent if at all under
“cis-directing” conditions, appears as the major
product of reduction by a dissolving metal strengthens
our conclusions as to the respective configurations
of the inosamines from scyllo-mesoinosose.
The preparation of both epimers under
non-enolizing conditions confirms the assumption
of the Illinois workers that the hydroxyl groups
in both compounds retain the configuration of
the parent inosose. The yields obtainable by
the procedures described herein are considerably
improved over those from the Raney nickelammonia
reduction. A further advantage of the
sodium amalgam method for preparing scylloinosamine
is that a solution of scyllo-meso-inosose
to which hydroxylamine has been added may be
reduced directly after it has stood a short time.
This makes unnecessary the two-step isolation of
the oxime which may be difficultly obtainable12
from other inososes.
[Edited on 28-3-2006 by solo]
Attachment: Stereochemical Studies in the Aminodesoxyinositol .pdf (900kB) This file has been downloaded 648 times
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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