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Please login to access the full content or check if you have access via Variation 1: Palladium-Catalyzed Cycloisomerization of Enynes

DOI: 10.1055/sos-SD-046-00090

Gandon, V.; Thorimbert, S.; Malacria, M.Science of Synthesis, (200946214.

Palladium is a versatile transition metal which has been used extensively to perform cycloisomerizations.[‌125‌‌127‌] In 1985 the use of palladium(II) complexes for the carbocyclization of 1,6-enynes 144 into five-membered-ring exocyclic 1,3-dienes 145 was reported for the first time,[‌128‌] and since then this work has been the subject of further studies.[‌129‌‌132‌] Most of the results obtained have been reviewed from a synthetic[‌133‌,‌134‌] and a mechanistic point of view.[‌135‌‌137‌] In general, the reactions of 1,6-enynes give a mixture of 1,4- and 1,3-dienes, but 1,4-dienes with certain substitution patterns can be formed exclusively when specific catalysts are employed (Scheme 49).[‌128‌‌131‌]

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