Orthogonal Pd- and Cu-Based Catalyst Systems for C- and N-Arylation of Oxindoles
摘要:
In the cross-coupling reactions of unprotected oxindoles with aryl halides, Pd- and Cu-based catalyst systems displayed orthogonal chemoselectivity. A Pd-dialkylbiarylphosphine-based catalyst system chemoselectively arylated oxindole at the 3 position, while arylation occurred exclusively at the nitrogen using a Cu-diamine-based catalyst system. Computational examination of the relevant L1Pd(Ar)(oxindolate) and diamine-Cu(oxindolate) species was performed to gain mechanistic insight into the controlling features of the observed chemoselectivity.
The disclosure is directed to: (a) phosphacycle ligands; (b) methods of using such phosphacycle ligands in bond forming reactions; and (c) methods of preparing phosphacycle ligands.
The disclosure is directed to: (a) phosphacycle ligands; (b) catalyst compositions comprising phosphacycle ligands; and (c) methods of using such phosphacycle ligands and catalyst compositions in bond forming reactions.