Comments on: Huckel’s Rule: What Does 4n+2 Mean?

By: Mapato Juma

Mapato Juma — Mon, 06 Feb 2023 10:03:42 +0000

Thank you for your information. Found it helpful, be blessed.

By: Suman Mahato

Suman Mahato — Sun, 17 Apr 2022 12:36:19 +0000

Thank you for the simple explanation .

By: James Ashenhurst

James Ashenhurst — Fri, 02 Oct 2020 15:34:09 +0000

In reply to Ashish Varade. Treat each aromatic ring individually.

By: Ashish Varade

Ashish Varade — Thu, 01 Oct 2020 05:24:56 +0000

Is 1,3,5 triphenylbenzene aromatic? As number of electron become 4x(4+2) = 24 which follow antiaromatic rule.

By: James Ashenhurst

James Ashenhurst — Thu, 07 Nov 2019 21:28:56 +0000

In reply to Trevor.

This is a completely valid criticism. I should be answering the “question behind the question” here. The specific details are on this post:
https://www.masterorganicchemistry.com/2017/02/23/rules-for-aromaticity/#five
but including a discussion on this post would also be useful. Thanks for the feedback.

By: Trevor

Trevor — Sat, 02 Nov 2019 20:06:48 +0000

You are correct to say that n isn’t in the molecule, but yet you fail to show your students how to find the n. Not once did you even teach anything over as to where the n actually comes from. I just started studying this in organic chemistry 2 and I’m still researching this myself. I came to this article thinking I got it down, but yet it still fails to teach students how to find n.

By: James Ashenhurst

James Ashenhurst — Mon, 01 Jul 2019 21:08:08 +0000

In reply to Chanda. Count the pi electrons. The first case has two pi electrons (2 in the pi bond, zero in the p orbital of the carbocation), which is a Huckel number. The second case has 4 pi electrons (2 in the pi bond, 2 in the p-orbital of the carbon which bears the negative formal charge). 4 is not a Huckel number. It is not aromatic.

By: James Ashenhurst

James Ashenhurst — Mon, 01 Jul 2019 21:05:54 +0000

In reply to lanya. p orbitals must align themselves in the same plane in order to establish conjugation. If the molecule is not "flat", i.e. if the orbitals are not aligned in the same plane, then aromaticity is not possible.

By: James Ashenhurst

James Ashenhurst — Mon, 01 Jul 2019 21:04:37 +0000

In reply to sabine obagi. Sure. That works.

By: James Ashenhurst

James Ashenhurst — Mon, 01 Jul 2019 21:04:27 +0000

In reply to Rik Daems. Yes, but only one orbital per atom may align with the pi system.