作者:Patrick H. Dussault、Todd A. Anderson、Michael R. Hayden、Kevin J. Koeller、Q. Jason Niu
DOI:10.1016/0040-4020(96)00744-2
日期:1996.9
diastereoselection is also observed for distal addition of 3O2. The extent of olefin isomerization observed during radical oxygenations can be correlated with steric constraints on the intermediate pentadienyl and peroxyl radicals and may be relevant to literature reports of olefin isomerization during enzymatic oxygenations of unnatural fatty acids.
将单线态氧(1 O 2)添加到辅助束缚的1,4-二烯的近端烯烃中以及将三线态氧(3 O 2)添加到相应的戊二烯基的近端位置中均产生适度的共轭二烯氢过氧化物到高的非对映异构体过量。由于缺乏对烯烃构象的控制,对于向Z,Z-庚二烯的远端烯烃加成1 O 2,观察到可忽略的立体选择。尽管有证据表明戊二烯基是高度受约束的中间体,但远端添加3 O 2的非对映选择性也很差。。自由基氧合期间观察到的烯烃异构化程度可能与中间戊二烯基和过氧自由基的空间限制相关,并且可能与非天然脂肪酸酶促氧合期间烯烃异构化的文献报道有关。