Synthesis And Study Of Hydrocarbon Compounds With Double Cage Structure

ince their initial synthesis was reported by Eaton in 1964,cubane and its derivativeshave been extensively studied by chemists.Because of their high positive heats of formation,high density and better thermal stability,these kinds of compounds have significant potential for military applications as high energy density materials.With the development of cubane and its derivatives,some of them are used in medicinal chemistry.Based on the existing work,a new kind of hydrocarbon compounds with double cage structure was designed and its synthesis was studied.In this study,the structure of caged hydrocarbon compounds was synthesized by using cyclooctatetraene(COT).COT is an important raw material for organic synthesis,which is no longer produced on an industrial scale,and the price of this compound are quite expensive.In this paper,COT was prepared by the polymerization of acetylene and the influences of reaction temperature,reaction time,type of catalyst and amount of catalyst have been tested on the synthesis of COT.When Ni(acac)2 was used as the catalyst of acetylene polymerization,the conversion of acetylene could reach to 91.6% and the selectivity of COT was up to 58.7%and the yield was about 53.8% under the optimal reaction conditions(T = 70 ℃,t = 2 d,cat =2%).Next,the [2+2] photocycloaddition of nonconjugated alkenes was investigated in this study.Various of attempts were made to make photocycloaddition reaction carried out effectively,such as the reaction time,the type of photosensitizer and the choice of the reaction solvent.Based on that,the target compound was synthesized and the synthesis route was optimized and the optimum condition was confirmed.When the reaction time is 2 h and the reaction temperature is 90 ℃,compound a was hydrolyzed to obtain compound b and the yield is up to 90.7%.When the reaction time is 3 h and the reaction temperature is 120 ℃,compound b was dehydrated to obtain compound c and the yield is up to 84.2%.When the reaction time is 15 h and the reaction temperature is 180 ℃,compound d was synthesized by the Diels-Alder addition of compound c and the yield is up to 56.9%.The fifth step that the intramolecular [2+2] photocycloaddition of compound d has not been synthesized successfully,the reason may be that the UV wavelength of the High-pressure mercury lamp don’t match the maximum absorption wavelength of the nonconjugated alkenes.Therefore,itis the key for the synthesis of hydrocarbon compounds with cage structure to study photocloaddition deeply.