Filemon
Hazard to Others
Posts: 126
Registered: 26-4-2006
Member Is Offline
Mood: No Mood
|
|
Reactivity amide
May a primary amide substitute a alkyl halide?
|
|
|
Klute
International Hazard
Posts: 1378
Registered: 18-10-2006
Location: France
Member Is Offline
Mood: No Mood
|
|
Do you mean may a primary amide be alkylated by an alkyl halide?
yes, it can. Depending on the amide, NaOH/KOH with ot without a PTC can do the job, otherwise you need to get the NaH out and form the anion befor
eadding your alkyl halide. I haev recently requested several articles on the subject in the ref forum.
These could be usefull also:
alkyaltion of N-substitued phenylacetamides
Alkylation of N-substitued phenylacetamides: Benzylation of N-(4-chlorophenyl)-2-phenylacetamide
Look at the end of the experimental part of this article for an example of NaH alkylation in THF:
Synthesis of priamry amines by Pd2+ catalyzed deallylation
Hope it helps.
But if this is too form a primary amine by hydrolysis of the resulting secondary amide, you would better be off doing a Gabriel synthesis, the
alkylation is much cleaner...
For secondary amines, this seems like a good route that avoids LiAlH4 reduction of amides. Reductive alkyaltion with short chain aldheydes
(formaldehyde) seems pretty tricky and dialkylation happens to a certain extent.
[Edited on 12-8-2008 by Klute]
\"You can battle with a demon, you can embrace a demon; what the hell can you do with a fucking spiritual computer?\"
-Alice Parr
|
|
|
Filemon
Hazard to Others
Posts: 126
Registered: 26-4-2006
Member Is Offline
Mood: No Mood
|
|
| Quote: | Originally posted by Klute
Do you mean may a primary amide be alkylated by an alkyl halide?
|
Exact. It is what wanted to know. They are resistant to the attacks of the alkyl halides.
Thank you.
|
|
|
Klute
International Hazard
Posts: 1378
Registered: 18-10-2006
Location: France
Member Is Offline
Mood: No Mood
|
|
| Quote: | | They are resistant to the attacks of the alkyl halides. |
Is that a claim, or a question? Because the final point is they are not... Of course, other more nucleophilic groups would be alkylated before an
amide in the same molecule, but upon heating with alkyl halide, amides can be N-alkylated. That depends strongly on the structure of the amide, of the
alkyl halide, and of the reaction conditions.
In one of the above articles, they details the different products obtaien din different condition (neutral, basic), giving rise to N-, O- or even
C-alkylation products.
I'm afraid without any more info on what you want to know, and on the compounds, it impossible to give a definate answer.
\"You can battle with a demon, you can embrace a demon; what the hell can you do with a fucking spiritual computer?\"
-Alice Parr
|
|
|
Nicodem
Super Moderator
Posts: 4230
Registered: 28-12-2004
Member Is Offline
Mood: No Mood
|
|
Some amides get alkylated particularly easily with strong alkylating reagents. For example, N,N-dimethylformamide gets O-methylated with
dimethylsulfate just by letting the mixture of the two standing for a longer time.
…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!
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
