N-Heterocyclic carbene-catalyzed [3 + 2] annulation of bromoenals with 3-aminooxindoles: highly enantioselective synthesis of spirocyclic oxindolo-γ-lactams
作者:Kun-Quan Chen、Yao Li、Chun-Lin Zhang、De-Qun Sun、Song Ye
DOI:10.1039/c5ob02466h
日期:——
The chiral N-heterocycliccarbene-catalyzed [3 + 2] annulation of α-bromoenals and 3-aminooxindoles was developed, giving the corresponding spirocyclic oxindolo-γ-lactams in good yields with high diastereoselectivities and enantioselectivities.
conversion of 3-aminooxindoles for the diastereo- and enantioselective synthesis of homoallylic aminooxindoles has been described. The asymmetric allylicalkylation of 3-aminooxindoles with allyl carboxylates proceeded smoothly to afford a series of chiral 3-allyl-3-aminooxindoles. This work offers an alternative route to build these scaffolds. The application of this protocol is also highlighted by
Cobalt-Catalyzed Peroxidation of 2-Oxindoles with Hydroperoxides
作者:De-Long Kong、Liang Cheng、Tao Yue、Hong-Ru Wu、Wei-Chun Feng、Dong Wang、Li Liu
DOI:10.1021/acs.joc.6b00622
日期:2016.7.1
A highly efficient and facile cobalt-catalyzed C–H activation and peroxidation of 2-oxindoles was reported, which provides a new pathway for the synthesis of biologically active 3-peroxy-2-oxindoles from readily available starting materials in excellent chemical yields. The resulting products could be further transformed into various substituted 3-peroxyoxindoles in good to excellent yields. The developed
copper-catalyzed intramolecular C(sp2)–N cross-coupling reaction of 3-aminooxindoles with 2-bromobenzyl bromides, a wide range of 2,3′-spirobi[indolin]-2-ones were smoothly obtained in moderate to good yields. A plausible catalytic cycle for this tandem reaction process was proposed based on the control experiments. This study represents a new perspective for the synthesis of structurally diverse spirocyclic oxindoles