bascity on aromatic compound/ aromaticity

[gomawum]

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1. Benzene with amine (ph-NH2)

or

2. Benzene with (2-amine)-diethyl (ph-CH2-CH2-NH2)

isn't 1 stronger activating group than 2?
I don't see how 2 is stronger base than 1.




also I don't see why protonation of pyrrole destroys armoaticity.
protonation makes two lone pairs on nitrogen, but if I remember correctly from my ochem class, one lone pair is joined by conjugated planar pi orbitals whereas one is not, so aromaticity is maintained.
(I'm referring to my old ochem notes, and it said: because since one lone pair is not included in the conjugated pi orbitals, the pair is not included in huckle's rule 4n+2, so there are 6 e- that are on same plane whereas 2 e- is not)

 

[gomawum]

oh.. nvm on first question, it was due to resonance.

 

[TheWiredNerv]

oh.. nvm on first question, it was due to resonance.

Make sure you truly understand why resonance is the answer!

 

[Orgodox]

also I don't see why protonation of pyrrole destroys armoaticity.
protonation makes two lone pairs on nitrogen, but if I remember correctly from my ochem class, one lone pair is joined by conjugated planar pi orbitals whereas one is not, so aromaticity is maintained.
(I'm referring to my old ochem notes, and it said: because since one lone pair is not included in the conjugated pi orbitals, the pair is not included in huckle's rule 4n+2, so there are 6 e- that are on same plane whereas 2 e- is not)

Pyrrole already has one H on the Nitrogen. If you protonate the Nitrogen then the ring which was aromatic due to the the 6 e's (2 from the lone pair) only has 4 electrons! Check out the structure.
You are correct though that normally only one of the lone pairs is counted towards aromaticity because the another lone pair would be in a different plane. This is not the case here Pyrrole onl has one lone pair available.

 

[PreDent2009]

For the aniline (ph-NH2), the ring is electron withdrawing which actually stabalizes the base and makes it weaker due to resonance. For the (ph-ch2ch2NH2), the R alkyl groups actually are donating electron density towards the amine group, essentially destabalizes the base, making it stronger. Hope that helps.