Electrofugal Fragmentation of Alkylcobalamin Derivatives Using Cob(I)Alamin and Heptamethyl Cob (I)yrinate as Catalysts
作者:Albert Fischli
DOI:10.1002/hlca.19820650406
日期:1982.6.16
involved, the transfer of electrons to the intermediate alkylcorrinoids (13–15, 17–19, see Schemes 12 and 14) is shown to be rate-limiting. Comparing the two catalytic species 1(I) and 2(I), it is shown that the ribonucleotide loop protects intermediate alkylcobalamins to some extent from an attack by electrons. The protective function of the ribonucleotide side-chain is shown to be present in alkylcobalamins
穗轴(I)alamin-(1(I) )和七甲基钴(I)ynnate-(2(I) )催化的环氧化物为相应的饱和烃被检查345的转化(参见方案1和3-5) 。下的反应条件下,环氧烷基酯3通过催化剂开始与适当的形成(B-羟烷基)的-corrinoid衍生物(13,14,17,18,参见方案12和14)。受到电子转移至Co-corrin-π系统的触发,中间体的Co,C键断裂,生成乙酸烯基酯4(cf. 在电真菌裂解之后的方案12和14)(参见方案2和12)。的双键4也由催化剂攻击,导致相应alkylcorrinoids(15,19,参见方案12和14),其又被从金属锌,在系统中的电子源的电子还原,诱导还原裂解Co,C键的结合以及饱和单乙酸酯5的产生(参见方案2、5和12)。在所涉及的步骤的级联中,电子转移到中间的烷基氢化可的松(13-15,17-19,参见方案12和14)被示出为限速。比较两个催化物