joe_aldehyde
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monoalkylamination of secondary alkylhalides?
hello.
i know and have researched everything i could find about amination of halides, is the only way of effecting the monoalkylamination of a halide in
keeping the substrate concentration low vs the amine compound?
the gabriel synthesis using k-phthalimide isn't suitable here, as the secondary amine is the desired product.
[Edited on 26-3-2005 by joe_aldehyde]
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runlabrun
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This was discussed over at WD, search there for gabriel synthesis thread.
Secondary halides, lets use 2-bromohexane... under direct amination with methylamine will result in methylammonium bromide and 1-hexene with
2-aminohexane as a minor product.
Pressure has been known to help but yields are still low...
Gabriel reagents as discussed in the thread at WD are not just potassium phthalimide, read the thread over there for info.... its got some good info,
its in the advanced dreaming forum.
-rlr
[Edited on 27-3-2005 by runlabrun]
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joe_aldehyde
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so, what is WD anyways? all these acronyms don't mean the slightest thing to me.
i'm not trying to make a primary amine, this can in the case i'm working on be established by reduction of a nitroalkene.
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solo
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Re: what is WD?
WD=Wetdream forum , located at ........
http://www.wetdreams.ws Note: you need to register to access the forum .....
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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joe_aldehyde
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thanks.
but the stuff mentioned there isn't really helpful, as said - pure secondary amines via alkylhalides seems a very much impossible dream. anyways,
i found out that most likely the ever-cheap saccharin can be used as the gabriel reagent (50$/kg) 
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solo
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Not sure what you of what you want , since the thread at WD wasn't what you meant, maybe this will be of some assistance to your unclear
question......solo
http://www.tokyokasei.co.jp/news/page/121aminosyn.html
.........excerp;
Fukuyama and co-workers have recently demonstrated the amination of alkyl halides and alcohols using the N-substituted sulfonamide 1.1a) Smooth
reactions of 1 occur with alkyl halides under basic conditions and alcohols under Mitsunobu conditions to provide o-nitrobenzenesulfonyl (o-Ns) amines
2. The various o-Ns amines (Alloc, Boc, Cbz) 2 obtained from these reactions can be deprotected, under the appropriate conditions, to afford the
monoprotected amines 3 and 4. Furthermore, 3 can be converted to the primary amine 5 in high yields via a second deprotection. Compound 4 can be
converted to the secondary amine 6 in high yields by repeating the alkylation and deprotection process.1b)
[ References ]
1) Synthetic utility of N-carboalkoxy-2-nitrobenzenesulfonamides
a) T. Fukuyama, M. Cheung, T. Kan, Synlett, 1999, 1301.
b) T. Kan, A. Fujiwara, H. Kobayashi, T. Fukuyama, Tetrahedron, 58, 6267 (2002).
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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joe_aldehyde
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ok, to be more specific:
there is eugenol, which can be demethylated by refluxing it in HBr (anybody ever tried - successfully?), and HBr will just as well be added to the
terminal double bond, resulting in a secondary halide. to eliminate the need of converting into an alcohol and subsequently into a ketone, one could
just as well use it as a substrate in the gabriel synthesis, but in this case, a secondary (n-methylated) amine is the desired product (anybody
figured out yet what this is gonna be for 
now what i would be interested in is a RXN that would (under workable conditions) afford the n-methylated amine, which is obviously not possible to
make by just tossing the halide into a MeNH2 solution.
in your post SOLO, i guess the Y-group on the nitrogen is NOT an alkyl chain. so this might not be useful instead of the easily obtainable
phthalimide.
i have found something else, but this is really a thing that needs a lot of preliminary work - the photoamination of methylstyrenes (google for it).
the big prob is the HP-Hg-Lamp for me, i have a 500W bulb but still missing the starting device and power supply. additionally, i am not very
comfortable operating such a powerful device without protectional measures...
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