Comments on: Elimination Reactions (2): The Zaitsev Rule

By: Madhav Mittal

Madhav Mittal — Mon, 06 May 2024 07:53:49 +0000

“This is because the transition state leading to the more substituted alkene is lower in energy and therefore will proceed at a higher rate”.
There will be partial double bond between the carbon atoms in the Transition state, so how can we compare the stability of partial bonds?
Can we compare them exactly in the same way as we usually compare stability of alkenes?

By: James Ashenhurst

James Ashenhurst — Mon, 12 Feb 2024 21:47:10 +0000

In reply to Anonymous. Right. In the E1 reaction (which this is an example of) deprotonating the C-H bond adjacent to a carbocation does not require a strong base. In the case of H2SO4, it's the water (H2O) leaving group that ends up acting as the base.

By: Anonymous

Anonymous — Mon, 12 Feb 2024 17:14:00 +0000

You mentioned that elimination reactions require a base, but in the first example you use sulfuric acid instead whereas it is the substrate that seems to be basic at the OH group. What’s going on?

By: Zaitsev’s Rule: Definition, applications, and examples

Zaitsev’s Rule: Definition, applications, and examples — Sat, 29 May 2021 07:22:42 +0000

[…] Anti-Zaitsev’s rule – Masterorganicchemistry.com […]

By: Ozzy

Ozzy — Thu, 25 Feb 2021 00:21:02 +0000

I’m glad I stumbled into this
I clearly understand now

By: Elimination ReactionsThe E2 Mechanism – A to Z Chemistry

Elimination ReactionsThe E2 Mechanism – A to Z Chemistry — Sun, 08 Nov 2020 06:06:21 +0000

[…] at this interesting result. What’s weird about this? Well, this seems to fly in the face of Zaitsev’s rule, right? Why don’t we get the tetrasubstituted alkene […]

By: T

Fri, 24 Jan 2020 08:57:21 +0000

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By: James

James — Mon, 20 Nov 2017 15:24:32 +0000

In reply to Janci. Conjugation indeed plays a role in alkene stability, but this post focuses on the relationship between carbon substitution and alkene stability. It can be hard to predict situations where multiple variables are in play and conflict, such as deciding whether a tetrasubstituted non-conjugated alkene will form as opposed to a disubstituted conjugated alkene. Hence this post tries to keep things simple.

By: James

James — Mon, 20 Nov 2017 15:20:49 +0000

In reply to Cartesian. The major product in the first reaction is attached to four individual CH3 groups, hence, "tetrasubstituted".

By: Janci

Janci — Sun, 19 Nov 2017 17:09:56 +0000

should we note here that double bond stability is not just about substitution but also about conjugation?