| Pages:
1
2 |
madscientist
National Hazard
Posts: 962
Registered: 19-5-2002
Location: American Midwest
Member Is Offline
Mood: pyrophoric
|
|
| Quote: | | Perhaps you meant PhCH2C(=O)CH2CH3 would result? |
Nope.
| Quote: | | Or anhydrous NH3 can react/dehydrate with esters, replacing the linking oxgen. --C(=O)NHCH2-- |
RCOOR' + NH3 ----> RCONH2 + R'OH
I weep at the sight of flaming acetic anhydride.
|
|
|
Anders2
Banned
Posts: 39
Registered: 4-9-2010
Member Is Offline
Mood: No Mood
|
|
Okay then,
What about acetic acid, condense with Analine to form the imine, CH3C(=NPh)NH(Ph), then react with Br2 using an oil soluble acid to form the C=C
double bonded tautomer, then reduce the sensitive N--Br back to NH, now use this:
BrCH2C(=NPh)NHPh to couple with PhMg ?
Those protective analines can be gotten rid off after
about that last one,
RCONH2 HOCH2R
you are probably correct, but that should not matter,
the RCONH2 can still be hydrolyze to the carboxyl salt with a base.
[Edited on 17-9-2010 by Anders2]
|
|
|
DDTea
National Hazard
Posts: 940
Registered: 25-2-2003
Location: Freedomland
Member Is Offline
Mood: Degenerate
|
|
Quote: Originally posted by Anders2  | Okay then,
What about acetic acid, condense with Analine to form the imine, CH3C(=NPh)NH(Ph), then react with Br2 using an oil soluble acid to form the C=C
double bonded tautomer, then reduce the sensitive N--Br back to NH, now use this:
BrCH2C(=NPh)NHPh to couple with PhMg ?
Those protective analines can be gotten rid off after
about that last one,
RCONH2 HOCH2R
you are probably correct, but that should not matter,
the RCONH2 can still be hydrolyze to the carboxyl salt with a base.
[Edited on 17-9-2010 by Anders2] |
Look at the mechanism for formation of a Schiff base. That lone pair is required to form the carbinolamine. When you've got an acid (acetic acid
here) and a base (aniline here), the first--and fastest--reaction is going to be a proton transfer, which means the Nitrogen's lone pair is no longer
free to react with the carbonyl. As such, this only really works with aldehydes and ketones.
Amide formation from carboxylic acids and amines also gives low yields--the equilibrium is pretty unfavorable here.
In Organic Chem, it's as important to know when something *won't* happen as it is to know when something *will* happen.
[Edited on 9-17-10 by DDTea]
"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.
|
|
|
Anders2
Banned
Posts: 39
Registered: 4-9-2010
Member Is Offline
Mood: No Mood
|
|
I obviously agree with everything above, I just thought the process would go without saying, so I did not elaborate.
Obviously RCOOH would have to be made to first condense with analine. RCONH(Ph) ,analogous to condensation of amino acids. (or SCl2 could be used to
form RCOCl which could then condense with an amine)
Then the condensation to the imine (with another PhNH2)would would be carried out under strongly basic conditions.
RCONH(Ph) + H2N(Ph) ==KOH==> RC(=NPh)NH(Ph) + H2O
|
|
|
| Pages:
1
2 |
![[*]](images/xpblue/default_icon.gif){kind=icon}
