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DOI: 10.1055/sos-SD-046-00090

Gandon, V.; Thorimbert, S.; Malacria, M.Science of Synthesis, (200946186.

Zirconacyclopentadienes react with quinones at room temperature using copper(I) chloride as the transmetalation agent to produce the corresponding dihydro-1,4-quinones; these products may then be oxidized into the 1,4-quinones using p-chloranil or 2,3-dichloro-5,6-dicyanobenzo-1,4-quinone. In some cases the required 1,4-quinone is obtained directly and, for example, the anthra-9,10-quinone 52 (R1=R2=Pr; R3=H; R4=Ph) is obtained when the corresponding zirconacyclopentadiene 50 is reacted with naphtho-1,4-quinone; the 4a,9a-dihydroanthra-9,10-quinone 51 (R1=R2=Pr; R3=H; R4=Ph) is not isolated (Scheme 20).[‌67‌]

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