Radical Additions of Alkyl 2-Haloalkanoates and 2-Haloalkanenitriles to Alkenes Initiated by Electron Transfer from Copper in Solvent-Free Systems
作者:Jürgen O. Metzger、Ralf Mahler、Gerald Francke
DOI:10.1002/jlac.199719971119
日期:1997.11
Alkyl 2-iodoalkanoates 2, and 2-iodoalkanenitriles 15 were added, with copper powder, to the 1-alkenes 1a, e, f, and h, and to the alkenes 1b, c, d, and g with a 1,2-dialkyl substituted double bond, to give, respectively, γ-lactones and 4-iodoalkanenitriles in very good yields. No solvent was used. The reaction is a free radical addition initiated by electron transfer from copper to the activated iodoalkane
将2-碘代链烷酸烷基酯2和2-碘代链烷腈15与铜粉一起添加到1-链烯1a,e,f和h中,并添加到具有1,2-的链烯1b,c,d和g中。二烷基取代的双键,以非常好的收率分别得到γ-内酯和4-碘代烷基亚腈。不使用溶剂。该反应是由电子从铜转移到活化的碘代烷烃引发的自由基加成。使用各个溴代化合物的产率较低。通过向反应混合物中添加化学计量的碘化钠,原位形成碘化合物,可以提高产率。如果是溴溴丙二酸甲酯,则为6,证明不需要添加碘化钠。通过考虑在碘转移到手性加合物自由基过程中形成的过渡态取代基的空间相互作用,合理化了相对的1,3-不对称诱导引起的加成反应的非对映选择性。