Hi bees!
I have searched and searched this site for information on this topic, but i have not found anything that directly describes the scheme i have pondered.
Well the basic idea came from
Post 475109
(Lego: "Amphetamines/PEAs w/o benzaldehyde or nitroethane", Novel Discourse), where they bromomethylate benzene in 86,5% yield with a VERY easy procedure. It's
almost a shake'n'bake procedure.
Is there any particular reason why this method has not been tested with benzodioxole? In
Post 360218 (missing)
(Rhodium: "3,4-Methylenedioxy-1-bromobenzene Synthesis", Newbee Forum), the chief says that benzodioxole is brominated in super high yields(91%) to 3,4-methylenedioxy-bromobenzene. Obviously this means that the methylendioxy bridge activates the correct sites on the aromatic ring. The only problems i can think of are the following:
1)
The bromomethylgroup is o,p-activating, compared to a bromo substitutent. This
might lead to bis-bromomethylated compounds. However, in
Post 475109
(Lego: "Amphetamines/PEAs w/o benzaldehyde or nitroethane", Novel Discourse), the same thing should apply. That is, that the group would activate the o,p-position for further bromomethylation, yet this does not happen when the reaction is run carefully. Any ideas if this would work or not?
2)
Perhaps the methylenedixoy-bridge does not like the bromomethylether formed in the reaction. Will the MD bridge get ruined from this reaction?
Those are the two only arguments that could ruin the route. If they do not, the rest would go like this:
i)
Benzodioxole is quite cheap and unwatched(44 euros / 100 g). This is bromomethylated ala
Post 475109
(Lego: "Amphetamines/PEAs w/o benzaldehyde or nitroethane", Novel Discourse)(the one w/o HBr) to yield 3,4-methylenedioxy-bromomethylbenzene.
ii)
The compound from reaction
i is purified and dried thoroughly, to be used in a grignard reaction. 3,4-methylenedioxy-bromomagnesiumbenzene is formed via the standard route with magnesium turnings and a little iodine crystal to initate everything. This is described in depth
here
(
https://www.thevespiary.org/rhodium/Rhodium/chemistry/phenylacetone.html#grignard)
iii)
With the magnesium-grignard compound at hand, this is reacted with acetonitrile also described
here
(
https://www.thevespiary.org/rhodium/Rhodium/chemistry/phenylacetone.html#grignard) under anhydrous conditions.
iv)
The product from
iii is either reduced rigth away with borohydride to give MDA or hydrolysed with water to give MDP2P. In the afforementioned text on rhodiums site, Poodle describes a 75-80% yield on regular P2P, and 80% when reduced directly to amphetamine.
Anyone have reasons why this would
not work? If it did work it sure would be an easy way to the goodies IMO
. The only timelimiting reaction is the bromomethylation which takes about 16 hours. The rest can be done in less than a days work...
Regards
Bandil