Development of broadly useful silacyclic templates for organic synthesis

This dissertation describes our progress in development of cyclic silanes as templates for organic synthesis and the applications in complex natural products synthesis.;Chapter I describes the development of a new strategy for acyclic polyol assembly based on catalytic enantioselective desymmetrization of cyclic silicon-containing templates. The discussion begins with a comprehensive review of catalytic enantioselective desymmetrization of prochiral compounds using nonenzymatic catalysts. Described next, is our development of a highly enantioselective, catalytic base-promoted rearrangement of silacyclopentene oxides, followed by conversion of the resulting silacyclic alcohols into a range of polyols. The chapter concludes with the preliminary results of other possible desymmetrization protocols based on the Heck and the Diels-Alder reactions.;Chapter II describes the application of enantioselective catalytic desymmetrization of acyclic silanes to the synthesis of herbarumin I and pinolidoxin, and our finding of the reversibility of the ring-closing metathesis in this medium-ring system.;Chapter III describes our studies towards a fully stereocontrolled synthesis of neodysiherbaine A, a highly potent epileptogenic excitatory natural product. The account begins with a discussion of an isolation of neodysiherbaine A, structure determination, biological profile and previous synthesis of this natural product. Presented next is our general strategy for the assembly of neodysiherbaine A, featuring a palladium-catalyzed oxycarbonylation to rapidly assembly a dioxobicyclic core of the natural products, followed by the amino acid side-chain installation. The chapter next describes the execution of this approach, which enabled the construction of all the required structural elements of the final target with only two deprotection steps remaining to complete the synthesis of neodysiherbaine A.;Experimental data and NMR spectra of important compounds are included in Chapter IV and appendices.