I was thinking would it be possible to do an enolate subtitution(nucleophilic substitution) of ethanamide with 1-Bromo-2,4-dimethoxybenzene. If the
following reaction is successful, then a clemmensen reduction will get rid of the ketone. The result would be 2,4-dimethoxyphenethylamine.
sargent1015 - 10-10-2012 at 16:40
CH3 is not a good leaving group ever... Just sayintetrahedron - 11-10-2012 at 01:29
Br- is the leaving group..that methyl must be a typo.sargent1015 - 11-10-2012 at 04:59
Oh I see it now. You would need a suitable catalyst to remove that BrNicodem - 13-10-2012 at 01:34
I was thinking would it be possible to do an enolate subtitution(nucleophilic substitution) of ethanamide with 1-Bromo-2,4-dimethoxybenzene.
The pKa of primary amide N-H is many magnitudes lower than that of its alpha C-H, so it is not possible to obtain an enolate by a monodeprotonation of
acetamide.
Otherwise alpha arylations of tertiary amide derived enolates are known. See the literature. Off course, they are not simple nucleophilic
substitutions, only formaly so. These reactions proceed by either via photochemical nucleophilic substitution (rarely preparatively useful, unless
intramolecular) or via oxidative insertion, ligand exchange and reductive elimination (and thus require a transition metal catalyst). For this later
type of arylations, see the chapter Direct Arylation via Cleavage of Activated and Unactivated C-H Bonds (M. Miura, M. Nomura) published in
Topics in Current Chemistry 2002, 219 .
Quote:
then a clemmensen reduction will get rid of the ketone. The result would be 2,4-dimethoxyphenethylamine.
There is no ketone carbonyl group in the putative product that you depicted. I believe you don't know what a ketone is. Please read about ketones.sargent1015 - 13-10-2012 at 09:42
The pKa of primary amide N-H is many magnitudes lower than that of its alpha C-H, so it is not possible to obtain an enolate by a monodeprotonation of
acetamide.
What if we protected the NH2? Would the single leftover hydrogen still have a lower pKa then the methyl's? I'm trying to think back to my
Organic 2 class
1-chloro-3,4-methylenedioxybenzene to 3,4-methylenedioxy-phenylacetaldehyde
ChemistryGhost - 26-10-2012 at 17:45
Can 1-chloro-3,4-methylenedioxybenzene react with acetaldehyde in an enolate substitution reaction to form 3,4-methylenedioxy-phenylacetaldehyde. It
seems likely.
3,4-methylenedioxy-phenylacetaldehyde.
UnintentionalChaos - 26-10-2012 at 18:06
Go read up on aromatic reactivity and mechanisms and you'll quickly see that this is impossible.
