首页 | 本学科首页   官方微博 | 高级检索  
     


Zur übergangsmetallkatalysierten nucleophilen Epoxidringöffnungsreaktion
Authors:Frau G Lauterbach  G Posselt  R Schfer  D Schnurpfeil
Abstract:The Transition Metal Catalyzed Nucleophilic Epoxide Ring Opening Reaction The catalytic influence of MoO2(acac)2
  • 1 Acac-Acetylacetonat
  • , Mo(CO) 6 , MoCl 5 , WCl 6 and TaCl 5 on the reaction of 1,2-epoxy-octane with ethanol at 100°C in dioxan or chlorobenzene as solvents is proved. Water and hydroperoxides react with a higher rate than alcohols. When changing from primary to secondary and tertiary alcohols a decrease of the reaction rate is observed. 2,3- and 3,4-Epoxyheptane and cis- and trans-4,5-epoxy-octane react more slowly than the corresponding 1,2-epoxides. Epichlorhydrin and methylglycidether react with a lower, cyclohexene oxide, styrene oxide and norbornene oxide react with a higher rate than 1,2-epoxyoctane. The reactivities of the two dicyclopentadiene monoepoxides correspond with the reactivities of the norbornene and cyclopentene oxides. In the molybdenum catalyzed epoxide ring opening reaction an isomer distribution appears in favour of the 1-hydroxy-2-ethoxy-alkane 2 . A mechanism in the coordination sphere of the transition metal complex is proposed.
    Keywords:
    设为首页 | 免责声明 | 关于勤云 | 加入收藏

    Copyright©北京勤云科技发展有限公司  京ICP备09084417号