A Single Terminal [NiII-OH] Catalyst for Direct Julia-Type Olefination and α-Alkylation Involving Sulfones and Alcohols.

A terminal [NiII-OH] complex 1, supported by triflamide-functionalized NHC ligands, showed divergent reactivity for the reaction of sulfone with alcohol, contingent on base concentration, temperature, and time. Julia-type olefination of alcohols with sulfones was achieved using one equiv. of base, whereas lowering base loading to 0.5 equiv. afforded α-alkylated sulfones. Besides excellent substrate scope and selectivity, biologically active stilbene derivatives DMU-212, pinosylvin, resveratrol, and piceatannol were synthesized in high yield under Julia-type olefination conditions. An extensive array of controlled experiments and DFT calculations provide valuable insight on the reaction pathway.

Hydroarylation of alkynes via dual ortho-C-H functionalization of diaryl amines on a dicopper(I,I) platform.

A pyridine and morpholine-functionalized dicopper(I,I)-NHC complex (1) features both terminal and bridging coordination modes of NHC within the same molecule, and catalyzes dual ortho-C-H functionalization of diaryl amines for the hydroarylation of alkynes. A bimetallic construct in catalyst 1 allows sequential activation of ortho-C-H bonds of two aryl units to furnish a wide variety of 9,10-dihydroacridine derivatives without the explicit use of a directing group.