Development of Biligands Magnesium Catalysis in Asymmetric Conjugate Reactions of C3-Pyrrolyl-Oxindoles

A magnesium
catalyzed asymmetric conjugate reaction of C3-pyrrolyl-oxindoles
with terminal alkynones is presented. The current asymmetric conjugate
reaction relies on the development of novel combinational magnesium
catalysis involving two chiral ligands. The current protocol proceeds
smoothly and gives the corresponding enantioenriched 3,3-disubstituted
oxindole skeletons with good enantioselectivities. Furthermore, the
conjugate adducts could be transferred to spiro oxindole structures
containing an eight-membered ring in high ee values.

本研究报道了C3-吡咯基吲哚酮（C3-pyrrolyl-oxindoles）与端基炔酮之间的镁催化不对称共轭反应。该反应体系依托于一种由两种手性配体协同构筑的新型组合镁催化体系。该反应可平稳进行，能够以优异的对映选择性得到相应的对映富集型3,3-二取代吲哚酮骨架。此外，所得共轭加成产物可进一步转化为含八元环结构的螺环吲哚酮类衍生物，且产物具有较高的对映体过量（ee）值。