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3,4 dimethoxy phenethyl alcohol as precursor?

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psyloxy:
Well, there are easier ways to get 3,4-diMeO-P2P but there's still intresting stuff to discuss.

I just had a look into several books but I couldn't find Weinrab mentioned anywhere so I guess a bit. Weinrab amide = ...dimethylamide ? Dimethylamides react with grignards to produce dimethylamine and a new carbonyl-compound. So if this is what we are talking about then why not use BzMgCl and N,N-dimethylacetamide to get P2P ?

--psyloxy--

Beaker:
Would be brominated in the 5-position. At least, that's what happens with the related phenethylamine.

I just had a look into several books but I couldn't find Weinrab mentioned anywhere so I guess a bit. Weinrab amide = ...dimethylamide ?
--- End quote ---
WeinrEb amine = N,O-dimethylhydroxylamine. Condense with a suitable carboxylic acid derivative and you've got a WeinrEb amide.

Dimethylamides react with grignards to produce dimethylamine and a new carbonyl-compound.
--- End quote ---
This does not cleanly give ketones unless a huge excess of the amide is used, if at all. Thus, if the amide is the limiting reagent(as in this case), your yields would suck ass. With the Weinreb amide, low tempetature addition of a slight excess of the grignard or organolithium reagent usually gives a 80-95% yeild of the ketone.

So if this is what we are talking about then why not use BzMgCl and N,N-dimethylacetamide to get P2P ?
--- End quote ---
That's not what he was talking about.

psyloxy:
Thanks for all the clarification!

So, even if it was not what we were talking about, BzMgCl and the Weinreb amide of AcOH would give P2P in good yield ?

--psyloxy--

Beaker:
I don't know. Benzyl grignards are funny. They tend to give side products where they are alkylated at the position on the ring ortho to the -CH2-MgCl position.

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