Electrophilic lactonization as a tool in acyclic stereocontrol. Synthesis of serricornin
作者:Paul A. Bartlett、David P. Richardson、Joel Myerson
DOI:10.1016/0040-4020(84)80015-0
日期:1984.1
Several electrophilic lactonization procedures have been explored as a means of functionalizing olefinic carboxylic acids with relative asymmetric induction, Iodolactonization of δ,ϵ -unsaturated acids under conditions of thermodynamic control exhibits good 1,2- and 1,3-, but not 1,4-induction in the formation of δ-lactones. Mercurilactonization proceeds with good stereocontrol in the formation of
已经探索了几种亲电内酯化方法,作为通过相对不对称诱导官能化烯烃羧酸的方法,在热力学控制条件下,δ,β-不饱和酸的碘内酯化表现出良好的1,2-和1,3-,但1,4不-诱导δ-内酯的形成。巯基内酯化在形成γ-内酯和δ-内酯(1,2-诱导)时都具有良好的立体控制,但是在还原性脱汞过程中难以消除。用N-(苯基硒代)邻苯二甲酰亚胺进行的苯基硒代内酰胺化显然是动力学控制的,可对10(一种强空间偏向的底物产生δ-内酯)进行高诱导,而对16则不这样做。,导致生成γ-内酯。相反,在26(10的酯)的情况下,羟甲基内酯化在良好的立体控制下进行,而16的类似酯则没有。将由10和13的环化得到的内酯以立体特异性方式转化为(±)-sercorncornin的每种立体异构体。