Deprotonation of a simple borylated allylic sulfone and subsequent alkylation with certain unsaturated electrophiles provide substrates that are easily converted into functionalized alkenyl boronates with ring sizes from five- to seven-membered. A Chan-Lam reaction on one such substrate afforded an alkoxyallylic sulfone that was readily converted via a (4 + 3)-cycloaddition to a polycycle possessing the ABC ring substructure of ingenol.
Radical isomerization of borylated allylic sulfones
作者:Erich Altenhofer、Michael Harmata
DOI:10.1016/j.tetlet.2014.12.047
日期:2015.6
We report a preliminary study of the radicalisomerization of borylated allylic sulfones to their more thermodynamically stable isomers. This reaction is important as it provides access to structurally unique vinyl boronates not easily accessible by other means.