Rhodium(i)-catalyzed cascade C(sp2)-H bond alkylation - amidation of anilines: phosphorus as traceless directing group

We introduce a versatile Rh(i)-catalyzed cascade reaction, combining C(sp2)-H bond functionalization and amidation between N-arylphosphanamines and acrylates. This innovative approach enables the rapid synthesis of dihydroquinolinone scaffolds, a common heterocycle found in various pharmaceuticals. Notably, the presence of the phosphorus atom facilitates the aniline ortho-C(sp2)-H bond activation prior to N-P bond hydrolysis, streamlining one-pot intramolecular amidation. Moreover, we demonstrate the applicability of this reaction by synthesizing an antipsychotic drug. Detailed mechanistic investigations revealed the involvement of a Rh-H intermediate, with substrate inhibition through catalyst saturation.

Upgrading Carbazolyl-Derived Phosphine Ligands Using RhI-Catalyzed PIII-Directed C-H Bond Alkylation for Catalytic CO2-Fixation Reactions

We report an Rh(I)-catalyzed C-H bond alkylation of PhenCarPhos [N-(2-(diphenylphosphaneyl)phenyl)carbazole] and some congener phosphine ligands with alkenes. The C-H bond functionalization occurred exclusively at the C1 position of the carbazolyl unit because the trivalent phosphine acts as a directing group. This protocol provides straightforward access to a large library of C1-alkyl substituted PhenCarPhos, which outperformed common commercial or unfunctionalized phosphines and their precursors in the Pd-catalyzed carbon dioxide-fixation reactions with propargylic amines.