Wheel of Benzyne

The magical benzyne intermediate!


The benzyne (or aryne or dehydrobenzene or dehydroarene) mechanism aka the elimination–addition mechanism, i.e., the opposite of SNAr (SN2Ar), or the addition–elimination mechanism, is one of the fundamental nucleophilic aromatic substitution (NAS) mechanisms.



Wheel of the benzyne intermediate: Click/tap to enlarge the image

Substrates -> Reagents/Conditions (on the infographic):

    1. o-Fluorohalobenzene -> Lithium/Magnesium
    2. Benzocyclobutenedione -> hν
    3. Phthalate dianion -> hν
    4. 1H-1λ6,2,3-Benzothiadiazole-1,1-dione (prepared from 2-Aminobenzene-1-sulfinic acid & Nitrous acid)
    5. 1H-Benzotriazol-1-amine -> Lead(IV) acetate
    6. 2-Diazoniobenzoate -> Î” or hν (prepared from Anthranilic acid & Nitrous acid)
    7. 2-(Trimethylsilyl)phenyl trifluoromethanesulfonate -> Tetrabutylammonium fluoride
    8. Halobenzene -> Base

    What other wheel(s) 🎡 of organic reactions would you like to see❓Questions❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com❗

    Reference:
    Valiulin, R. Organic Chemistry: 100 Must-Know Mechanisms; De Gruyter: Berlin, 2023.

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