An “Anti-Baldwin” 3-Exo-Dig Cyclization: Preparation of Vinylidene Cyclopropanes from Electron-Poor Alkenes
摘要:
Stabilized carbanions undergo an uncommon 3-exodig cyclization onto propargyl halides through an S(N)2' substitution. Propargyl iodides as electrophiles are necessary to achieve good yields (36-95%) for most substrates, although the usefulness of chlorides and bromides is documented. A variety of monocyclic and bicyclic; vinylidene cycloproparies can be prepared. These products are not available by standard carbene methodology.
An “Anti-Baldwin” 3-<i>Exo-Dig</i> Cyclization: Preparation of Vinylidene Cyclopropanes from Electron-Poor Alkenes
作者:Matthew J. Campbell、Patrick D. Pohlhaus、Geanna Min、Kohsuke Ohmatsu、Jeffrey S. Johnson
DOI:10.1021/ja803553a
日期:2008.7.1
Stabilized carbanions undergo an uncommon 3-exodig cyclization onto propargyl halides through an S(N)2' substitution. Propargyl iodides as electrophiles are necessary to achieve good yields (36-95%) for most substrates, although the usefulness of chlorides and bromides is documented. A variety of monocyclic and bicyclic; vinylidene cycloproparies can be prepared. These products are not available by standard carbene methodology.