The total synthesis of medicinally active compounds are important pursuits in the field of biomedical science. In line with our interest in the efficient total synthesis of biological active natural products, we are pursuing a program of research directed toward new carbon-carbon bond construction reactions, which simplify the assembly of the carbon back bone in complex natural products. The proposed research specifically examines the intramolecular iron(O) catalyzed diene to olefin cross-coupling reaction which have been underutilized as methodology for the preparation of functionalized carbo- and hetercyclic ring systems. The chemistry proceeds with novel aspects of regio- and stereochemical control including potential applications to transition metal catalyzed asymmetric synthesis. Detailed chemical studies of each of these aspects are proposed. The specific goals of our investigations in this research area are to define catalyst and substrate requirements which enable; 1) the efficient cross-coupling reaction at or near ambient temperatures; 2) the selection of, on the basis of metal center steric and stereoelectronic requirements, regioselective coupling to unsymmetrically substituted 1,3-dienes; 3) the use of the metal center as a template to control the relative stereochemistry in the bond formation between the two coordinated substrates; 4) the high levels of asymmetric induction by coordinating chiral ligands to the metal center; and 5) isolate and characterize new organometallic complexes relevant to the completion of the above objectives. By virtue of the highly versatile functionality which is retained on either side of the newly formed carbon-carbon bond, we anticipate that this chemistry will be broadly applicable to the improved syntheses of medicinally important compounds.
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