N-Heterocyclic carbene-catalyzed oxidative [3 + 2] annulation of dioxindoles and enals: cross coupling of homoenolate and enolate
作者:Xiang-Yu Chen、Kun-Quan Chen、De-Qun Sun、Song Ye
DOI:10.1039/c6sc04135c
日期:——
The N-heterocycliccarbene-catalyzed oxidative [3 + 2] annulation of dioxindole and enals was developed, giving the corresponding spirocyclic oxindole-γ-lactones in good yields with high to excellent diastereo- and enantioselectivities. The challenging aliphatic enals worked effectively using this strategy. The oxidative cross coupling of homoenolate and enolate via single electron transfer was proposed
Highly diastereo- and enantioselective NHC-catalyzed [3+2] annulation of enals and isatins
作者:Li-Hui Sun、Li-Tao Shen、Song Ye
DOI:10.1039/c1cc13860j
日期:——
carbene bearing a proximal hydroxy group derived from L-pyroglutamic acid was found to be an efficient catalyst for the [3+2] annulation of enals and isatins to give the corresponding spirocyclic oxindolo-gamma-butyrolactones in good yield with good diastereo- and enantioselectivities.