Metal-Catalyzed Transformations of Stereodefined Enol Triflates and Their Derivatives
The following dissertation will describe metal-catalyzed transformations of stereodefined enol triflates and their derivatives. Enol triflates are widely versatile synthetic building blocks in organic chemistry. This dissertation will demonstrate their utility by disclosing methods for the synthesis of racemic allenoates, fully substituted furans and γ-butenolides. The first method describes a robust synthesis of racemic allenoates via a palladium-catalyzed β-hydride elimination of (E)-enol triflates. This procedure accesses all four patterns of substituted allenoates from a single substrate class. The second method presents a mild synthesis of tri- and tetra-substituted furans via a ruthenium-catalyzed cyclization of diazoacetates, reagents derived from (Z)-enol triflates. This work also demonstrates the synthetic utility of substituted furans by obtaining butenolides through a highly regioselective method under mild acidic conditions. Finally, the third method utilizes the newly developed furans to accomplish a palladium-catalyzed benzylic migration of these substrates to yield γ-butenolides possessing a quaternary center.