Epoxidation of <i>trans</i>-Cyclooctene by Methyltrioxorhenium/H<sub>2</sub>O<sub>2</sub>: Reaction of <i>trans</i>-Epoxide with the Monoperoxo Complex
作者:Waldemar Adam、Chantu R. Saha-Möller、Oliver Weichold
DOI:10.1021/jo000564l
日期:2000.8.1
proceeds stereoselectively, the monoperoxo rhenium complex A, which is generated in situ during the catalytic cycle, is responsible for the facile deoxygenation, isomerization, and hydrolysis of the trans-epoxide. In the case of the homogeneous MTO/H(2)O(2) system, rapid decomposition of the catalytically active rhenium species into HReO(4) circumvents the formation of such side products. In contrast, for
与MTO / H(2)O(2),MTO / UHP和NaY / MTO / H(2)O(2)氧化剂的反式环辛烯(trans-1)的环氧化反应会导致反式/顺式的混合物-烯烃1,反式/顺式-环氧化物2和顺式-二醇3。虽然氧转移是立体选择性进行的,但在催化循环过程中原位生成的单过氧rh络合物A负责容易的脱氧,异构化,和反式环氧的水解。在均质MTO / H(2)O(2)系统的情况下,催化活性active种快速分解成HReO(4)可以避免此类副产物的形成。相反,对于非均相氧化剂MTO / UHP和NaY / MTO / H(2)O(2),具有催化活性的rh物种足够稳定,并且生存时间足够长,以促进观察到的副反应。