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The reaction of open-chain unconjugated dienes with palladium acetate in acetic acid was investigated with particular reference to the behavior of the two double bonds in the course of the acetoxylation. 1,5-Hexadiene produced 3-acetoxymethylenecyclopentane (64%), but 2,6-octadiene bearing two terminal methyl groups gave open-chain acetoxylated products: 3-acetoxy-1,6-octadiene (46%) and 7-acetoxy-2,5-octadiene (47%). The reactions of 1,6-heptadiene and diallyl ether are found to proceed via abnormal anti-Markovnikov addition to afford cis and trans 1-acetoxy-1,6-heptadienes (63%) and γ-acetoxyallyl allyl ethers (84%), respectively. No participation of the second double bond has been observed in the reaction of 1,7-octadiene. The behaviors of these dienes to palladium acetate can be reasonably explained by assuming the formation of π,σ-palladium species possessing a stable pseudo-six membered ring.

Wahrend aus dem Dien (I) mit Pd-acetat in Essigsaure das Cyclopentan (II) entsteht, werden mit dem Dien (III) die offenkettigen Produkte (IV) und (V) erhalten.