1, 2, 3, 4-tetraphenylnaphthalene
Synthesis of 1,2,3,4-tetraphenylnaphthalene by Diels-Alder Reaction between
Tetraphenylcyclopentadienone and Benzyne
TA: Karen Beckman
Chem 2311, Section 5
The purpose of this experiment is to synthesize benzyne formed by anthranilic acid and
isoamyl nitrite in situ, and to use benzyne synthesized (intermediate, as dienophile) and
tetraphenylcyclopentadienone (as diene) for preparing 1,2,3,4-tetraphenylnaphthalene through Diels-
Alder reaction. The final product is crystallized from its ethanol solution and collected by vacuum
H NMR spectroscopy of the product was obtained to characterize and
identify 1,2,3,4-tetraphenylnaphthalene and its purity.
Key features of this Diels-Alder reaction are: a. formation of benzyne intermediate from
diazonium salt through reaction between anthranilic acid and isoamyl nitrite; b. benzyne ring was
trapped onto the diene, tetraphenylcyclopentadienone, as soon as it was generated. A key reactive
intermediate of Diels-Alder reaction then formed and rearranged for aromatization. After loss of carbon
monoxide from the reactive intermediate, 1,2,3,4-tetraphenylnaphthalene would be obtained.