How to Figure out whether an Organic Compound Is Aromatic, Anti-aromatic or Non-aromatic - Part 3

How to decide on aromaticity?


Aromaticity is a chemical property in which a conjugated ring of unsaturated bonds, lone pairs (lp), or empty orbitals exhibits a stabilization greater than would be expected from conjugation alone.

Hückel's rule helps predict aromaticity albeit with limitations.

Question:

Is Cyclooctatetraene radical anion aromatic? If not, why?

Solution infographic:



Click/tap to enlarge the image

Cyclooctatetraenide dianion (COT²⁻): Cyclic, conjugated, 10-Ï€-e─ (satisfies Hückel's rule (n=2)), planar => aromatic.

Looking for an interesting infographic and a memorable mnemonic on aromaticity? Click HERE.

Amateur in aromaticity❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com❗

References:

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

(2) Wikipedia Contributors. Hückel’s rule. Wikipedia.

(3)    Wikipedia Contributors. Jahn–Teller effect. Wikipedia. https://en.wikipedia.org/wiki/Jahn%E2%80%93Teller_effect.

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