Synthesis And Characterization Of Rhenium Alkenylcarbynes And Rhenacycles

The transitional metallacycles,by introducing a transition metal fragment into organic carbocycles,are organometallic complexes that play an important role in modern organic reactions due to their unique reactivities and highly catalytic activities.This work reports the synthesis and characterization of a series of metal alkenylcarbyne complexes and rhenacycles with novel structure from the reaction of rhenium hydride and a variety of organic multiynes containing alkynol or terminal alkyne groups.There are five chapters:The first chapter mainly introduced the backgroup of metal alkenylcarbyne and metallacycles.The purpose of this dissertation was also presented in this section.The second chapter mainly studied the synthesis and reactivities of various rhenium alkenylcarbyne complexes generated from the reaction of rhenium hydride with methyldiphenylphosphine and alkynols.And tried to construct metallacycles through reversal synthesis.The influence of phosphine ligands on reactivity was studied.Moreover,a series of rhenium alkenylcarbyne with conjugated aryl groups was designed and prepared.Their UV-Vis absorption properties was also studied.The third chapter constructed dirhenadehydro[12]annulenes through the reaction of rhenium dichloroalkenylcarbyne with cesium fluoride.The dirhenadehydro[12]annulene was found to show as typical organometallic alkynyl complexes when reacting with HCl.The theoretical study showed that the frontier orbitals of dirhenadehydro[12]annulene is differernt to its parent octadehydro[12]annulene in spite of their similar π-bonding interactions.Compared to dichloroalkenylcarbyne,the dirhenadehydro[12]annulene has differernt electronic structure.The fourth chapter directly constructed various intramolecular alkenyl-coordinated rhenacycles and six-membered rhenacycles with carbene bond through the reaction of several metal hydride with terminal alkyne ligands.The synthesis of these noval structures is of great significance in the future.The fifth chapter summarized the work and discussed the prospective.