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Abstract
One of the areas of focus in the Takacs laboratories is the development of synthetic methodology using catalytic palladium for the formation of five- and six-membered carbocyclic ring systems. The palladium-mediated bisdiene to triene cycloisomerizations leading to five and six-membered rings in the absence of a trapping agent is described in this dissertation. The methodology has been successfully extended to electron rich dienes affording cyclized trienes in high yields and high diastereoselectivity. In the five-membered ring system where the cyclized triene is a mixture of double bond isomers, alkyl substitution, based on a literature precedent, has afforded the cyclized product stereoselectively and in excellent chemical yield. The mechanism of palladium-catalyzed cycloisomerizations and also palladium-mediated elimination of allylic acetates using isotopic labeling studies has been investigated. Preliminary results obtained from the mechanistic study argue against the commonly accepted $\beta$-hydride elimination mechanism.
