How to Predict and Compare the Rotational Energy Barriers of Different Molecules - Part 1

The rotational free energy barrier depends on the bond’s ability to rotate.


Less steric crowding & no partial/complete double bond character lower the rotational energy barrier. A free rotation is not allowed around a double bond; else, it would break the π─bond.  

Question:

Arrange the following compounds in the increasing order of their C-C bond rotations:

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Solution infographic:



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How is it❓ Let Chemaficionado know at mychemistryhomework@gmail.com❗

References:

(1)    Wikipedia Contributors. Aromaticity. Wikipedia. https://en.wikipedia.org/wiki/Aromaticity.

(2)    Wikipedia Contributors. Resonance (chemistry). Wikipedia. https://en.wikipedia.org/wiki/Resonance_(chemistry).

(3)    Chouhan, M. S. Advanced Problems in Organic Chemistry for JEE, 11th Ed.

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