Synthesis And Applications Of (E)-α-stannyl-α, β-unsaturated Esters In Highly Selective Synthetic Reactions

This dissertation describes the stereoselective synthesis of 1,1-difunctional group reagents-(E)-α-stannyl-α,β-unsaturated esters and their applications in high selective synthetic reactions.The palladium-catalyzed hydrostannylation reaction of alkynyl esters with tribu-tyltin hydride gives versatile (E)-α-stannyl-α,β-unsaturated esters which are new di-functional group reagents. Based on the reactivities difference of tributylstannyl and ester groups, we studied the Stille cross-coupling reaction of (E)-α-stannyl-α,β-unsaturated esters with alkenyl halides in the presence of Pd(PPh3)4/CuI to afford the corresponding 1,3-dienyl esters in high yields. We carried out the Stille cross-coupling reaction of (E)-α-stannyl-α,β-unsaturated esters with acetylenic bromides in the presence of Pd(PPh3)4/CuI to afford the corresponding 1,3-enynyl esters in high yields. We also investigated the tandem hydrostannyla-tion-Stille reaction of alkynyl esters with tributyltin hydride and alkenyl halides or acetylenic bromides, providing one pot stereoselective synthesis of 1,3-dienyl esters and 1,3-enynyl esters.