Stereoselective Synthesis Of β-Bromostyrene Derivatives And Its Applications

(E)-Vinyl bromides are important precursors in many useful organic trans-formations including the well-known Stille,Suzuki,and Sonogashira couplings,as well as the Buchwald methodology,to introduce new carbon-carbon bond and heteroatoms.They are widely used in medicines,pesticides,natural compounds and materials.This article has mainly studied the synthesis of kinds ofβ-bromostyrene derivatives.In chapter 1,the existenc and biological medicine values of the natural compounds containing the halogenated alkene structure are pointed out.Its applications and general synthetic method are also elaborated.In chapter 2,we studied the stereoselective synthesis of(E)-4-(2-bromovinyl)benzoic acid,(Z)-4-(2-bromovinyl)benzoic acid and(E)-4-(2-bromovinyl)phenol.These threeβ-bromostyrene derivatives are obtained in high yield.In chaper 3 and chaper 4,we studied the applications of the above threeβ-bromostyrene derivatives,which containing the structure of bromovinyl unit are prepared.We compared the solvent, the dosage of base,the reaction temperature and the reaction time and screen out the best reaction condition-benzene,equal DMAP and room temperature.In this condition,high yields are obtained in most reactions.In the other hand,we developed a one-pot synthetic procedure for preparation of 4-alkoxycarbonyl- and 4-aryloxycarbonyl-(E)-2-arylvinyl bromides from 4-(1,2-dibromo-2- carboxyethyl)-benzoic acid.In chapter 5,we studied the synthesis of(Z)-4-(2-bromovinyl)-benzenesulfonamide and 4- alkoxyl -and 4-aryloxyl-(E)-arylvinyl bromides.In the finality,the problems requiring further studies are discussed.