Comments on: Aromatic, Non-Aromatic, or Antiaromatic? Some Practice Problems

By: Bias Binte Kamal

Bias Binte Kamal — Sun, 23 Mar 2025 14:21:15 +0000

What’s the difference between non-aromatic and anti-aromatic?

By: James Ashenhurst

James Ashenhurst — Wed, 30 Oct 2024 13:44:06 +0000

In reply to fikremariam kassa.

“Are these molecules conjugated?” https://www.masterorganicchemistry.com/2011/03/08/are-these-alkenes-conjugated/

By: fikremariam kassa

fikremariam kassa — Mon, 28 Oct 2024 07:17:14 +0000

what do you mean conjugated? how to identifies the molecules are conjugate?

By: Victoria

Victoria — Thu, 25 Apr 2024 01:40:08 +0000

THANK YOU!!!! so helpful!!!!

By: James Ashenhurst

James Ashenhurst — Sat, 06 Aug 2022 02:50:43 +0000

In reply to Sakib. The molecule does not exist. However if you look at azulene, it's possible to push the arrows such that you get a cyclopentadienyl cation and a heptatrienyl anion, each of which are (in theory) anti aromatic. However based on the dipole moment the contribution of this resonance form is zero

By: Sak

Sak — Fri, 07 May 2021 07:11:34 +0000

I found a source saying cyclobutan-1,2,3-trione is aromatic .Is it correct? If yes please explain how?

By: Sakib

Sakib — Tue, 30 Mar 2021 08:50:21 +0000

What will be the aromaticity of a compound having both an aromatic and an antiaromatic ring? Eg- phenyl cyclobutadiene

By: James Ashenhurst

James Ashenhurst — Thu, 11 Mar 2021 17:42:09 +0000

In reply to Hayley. It's not conjugated all the way around the ring. If you look at the nitrogen you'll see that it is sp3 hybridized (attached to four sigma bonds). If it had an empty p orbital that would give it 5 orbitals which violates the octet rule!

By: James Ashenhurst

James Ashenhurst — Thu, 11 Mar 2021 17:25:15 +0000

In reply to Olly.

Because the ring meets the rules. : – )

The methyl group has no impact on the aromaticity. Aromaticity is determined by the pi-electrons (i.e. the electrons in the double bonds).

By: Hayley

Hayley — Thu, 11 Mar 2021 14:23:41 +0000

Hey James,
why is ”Pyrrole Conjugate Acid” not Aromatic? I assume, it has an empty p-orbital. And with this empty p-orbital, it is possible to build a conjugated phi orbital system with the rest existing phi-bonds.

Thanks in advance!