[briteyellowness]

if i start with aniline and i donate the lone pair of electrons to form a double bond with the ring so that the nitrogen now has a positive charge, do i disrupt the aromaticity of the ring?  will i have 7 or 8 electrons in the benzene ring now?  i guess i want to know is whether the double bond of nitrogen with the ring donates 1 or 2 electrons.

p.s.  where do people draw their little organic molecule pictures?  i'm very bad at explaining things.  thanks!

[Yggdrasil]

In aniline, the nitrogen will donate its lone pair (i.e. two electrons) to form a bond with the ipso carbon of the aromatic ring.  The aromaticity of the ring is not disrupted, because this is just a resonance structure, and resonance structures are not accurate representations of the true structure of the molecule.  In reality, the lone pair from the nitrogen forms a partial bond with the electrons in the aromatic ring.

So, in short, the nitrogen donates two electrons into the aromatic ring.

[movies]

It has to be one electron for the formal charges to work out!

[laotree]

Movies, you are always right.

[movies]

Not true, I've just made a lot of these mistakes before!

[The Good Doctor]

....in fact it's easy to see: if u delocalise your electron pair, you started with 2 electrons on your nitrogen (5 valence el.), to have then after delocalisation only 4 electrons as valence. So in fact like movies told u, the aniline just donate one electron. (N+). What result as one electron too much in your aromatic ring (Benzene is neg. charged).

 

[alphahydroxy]

p.s.  where do people draw their little organic molecule pictures?  i'm very bad at explaining things.  thanks!

you need to look at the links page here (i think) and look at the org chem drawing software. Chemdraw is the best (IMO) and this also lets you save your structures as gif files so you can post em easily. I think there is a free version for home/school use but you'll have to check this out. Isis/draw is another good one on but i don't think it lets you save gif or jpg files, this is free though. have a look at the links page and google it and you'll find stuff.