Cope rearrangements palladium® chloride

Overmann and Knoll have shown that many non-strained acyclic 1,5-dienes undergo clean Cope rearrangement at room temperature on treatment with catalytic amounts of bis(benzonitrile)palladium(ii) chloride (c.g. Scheme 98). There are, however, structural limitations to the types of 1,5-diene that undergo rearrangement under the reaction conditions used, since some substrates give no trace of the Cope-rearranged isomers. 

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