xxxxx
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Nitrogen adds to Double Bond
Methacrolin is added dropwise to Pthalimide in alcohol with some NaOEt and warmed at 40 - 50°C for 2 hrs to form
a-methyl-B-pthalimidopropionaldehyde. Y ca: 80% (F. e. s. O. A. Moe and D. T. Warner, Am. Soc. 71, 1251 (1949)).
I wanted to post this reference so I could ask if this reaction might be general to all alkenes.
I can´t be certain since the aldehyde group is electron withdrawing, but the nitrogen adds to the second carbon away from the aldehyde, maybe
because it is less hindered.
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morsagh
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This is conjugated alkene bond with aldehyde, so i guess that mechanism is 1,4 addition of nucleophille.
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zed
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No, not all Alkenes. It is a special case.
A similar reaction is found in the reaction of Phenethylamine with EthylAcrylate.
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Crowfjord
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It's definitely a 1,4 addition and it works due to the electronic withdrawing nature of the carbonyl. Also known as a Michael addition or Micheal
reaction.
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Eddygp
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Quote: Originally posted by Crowfjord | It's definitely a 1,4 addition and it works due to the electronic withdrawing nature of the carbonyl. Also known as a Michael addition or Micheal
reaction. |
I thought Michael was reserved exclusively for enolate (1,4-)conjugate addition, other Nu are just referred to as conjugate addition or 1,4-addition.
I can be wrong.
there may be bugs in gfind
[ˌɛdidʒiˈpiː] IPA pronunciation for my Username
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PHILOU Zrealone
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N adds to double bond...and so what...
It happens in a lot of examples into chemistry:
C=O bond addition
-imine formation from R-NH2
-amine formation from R-NH-R'
-oxyme formation from H2N-OH
-hydrazone and azine formation from H2N-NH2
-nitrimide formation from H2N-NO2
...
C=NH bond addition
-hydrazine, hydrazone and azine formation from H2N-NH2
...
C=C bond addition
-very common into aromatic serie like NO2(+) nitration, diazo coupling
-direct addition of HNO3, NxOy or Cl-NO or Cl-NO2 onto alkenes --> nitroso, nitro, nitrosonitro, dinitro, nitritonitro
...
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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Crowfjord
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Quote: Originally posted by Eddygp |
I thought Michael was reserved exclusively for enolate (1,4-)conjugate addition, other Nu are just referred to as conjugate addition or 1,4-addition.
I can be wrong. |
Whoops, yeah you're right. Michael reaction doesn't include nitrogen or oxygen nucleophiles. The mechanism of addition is pretty much the same though.
Michael Addition
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xxxxx
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Here is another paper describing the addition of nitrogen to a double bond. I'm not certain it would be general to all alkenes because of the ether
linkage.
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DDTea
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Searching for terms like "carboamination" and "hydroamination" will turn up a lot of methodology, with varying scopes and utility. Anti-Markovnikov
hydroamination of alkenes remains an important research goal. This review is probably a good starting point: http://pubs.acs.org/doi/abs/10.1021/cr0306788
"In the end the proud scientist or philosopher who cannot be bothered to make his thought accessible has no choice but to retire to the heights in
which dwell the Great Misunderstood and the Great Ignored, there to rail in Olympic superiority at the folly of mankind." - Reginald Kapp.
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xxxxx
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So the process might work with ethylene or propylene on a benzene ring with an electron-withdrawing subsituent or just a benzene ring if a base of
suffiencient strength is used?
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Maroboduus
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Methacrolein in that first diagram seems to have five bonds on the central carbon and an extra hydrogen atom.
WTF?
BTW: You should read some of this guy's other posts.
[Edited on 8-1-2017 by Maroboduus]
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zed
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No. Why don't you just tell the guys what you are trying to do?
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