To synthesize benzene, why not just buy it?
It surely isn't suspicious is it?
If it is, I wonder what's next? water?
You need to go back and read my opening a second time because obviously my very point escaped you the first time. I even had the decency to put "impractical" in the title. It is theory, not practice. MDMA is much "easier" to buy than to synthesize, so why bother making it too? "Just buy it."
And where is that second meta directing group your'e talking about? I don't see it in your illustrations, your right it is confusing when you have an invisible function on the ring (not included in the diagrams) that does this magic directing of ortho attack.
Again, you need to re-read what I said. The attack can go either ortho or para, and I explicitly stated that a)presence of a group at the para position prevents attack there, and b)both para and ortho attacks give the same result, it matters not.
And to Osmium:
You shouldn't take these mesomeric/resonance structures of reaction intermediates too literally, it's the same approximation that shows benzene to have 3 double bonds (which of course it does NOT have!). You can move the positive charge around the molecule, that doesn't mean that this positive charge really exists at these places. It is delocalized and just a very short lived intermediary anyway.
I try not to. I know about the resonance and the 3D reality of these things, but how else am I to depict the goings on if not in this manner? Don't expect me to code a nice little computer generated mpeg of shifts in electron density as the reaction progress. :P
If that was the case all the electrophilic substitution reactions on phenols would result in such non-aromatic products having this unsaturated ring and a ketone instead of a phenolic OH. But these reactions all yield a product which is still a phenol.
The energy gained from delocalizing the pi electrons in aromatics is so big that you need very convincig arguments to make a molecule give up its aromatic status voluntarily. Hydroquinone to benzoquinone is an example where it works, most of the time it won't.
Hmm, a very convincing point, sadly. Well that just sucks ass then. It was worth a shot though.
But, your statement about the hydroquinone to benzoquinone being a situation in which it works that way, makes me wonder: How do we know that this wouldn't possibly be another situation in which "it works that way"?
That second hydroxyl on hydroquinone/catechol must make the difference. I originally thought that one could reduce dihydroxyl functions with the same process, starting at the introduction of hydrazine stage, but it really isn't likely at all because you would have to get lucky enough to get two molecules of the hydrazine to attack the ring at the same time and react in the same manner. Not likely.
[EDIT]My apologies if this sounded very snappy. I am getting a bad habit of that. My points stand, but the tone can be ignored, there is no malice over here, just frustration.[/EDIT]
PrimoPyro