Longzhi Zhu

Nickel-catalyzed direct thiolation of C(sp(3))-H bonds in aliphatic amides.

Nickel-catalyzed thiolation of the inactivated methyl C(sp(3))-H bonds of aliphatic amides with disulfide is described. It is a novel strategy for the synthesis of thioethers with the ultimate goal of generating thioether carboxylic acids with various functional groups.

Copper-Mediated Remote C–H Bond Chalcogenation of Quinolines on the C5 Position

An efficient and convenient method is developed for the remote C-H bond chalcogenation of 8-aminoquinoline scaffolds on the C5 position that is geometrically inaccessible. The protocol makes use of inexpensive CuBr2 as mediator and shows good tolerance toward numerous disulfides/diselenides and aliphatic amides, giving the corresponding products in good to excellent yield.

Copper-mediated thiolation of carbazole derivatives and related N-heterocycle compounds

The copper-mediated direct thiolation of carbazole derivatives with disulfides via C(sp2)–H bond cleavage was developed for synthesizing diaryl and alkyl aryl sulfides. This reaction exhibits wide tolerance toward various functional groups giving the products in good yields without any additives or ligands, and can be easily extended to the synthesis of thioethers carrying a benzo[h]quinolone, 2-phenylquinoline, or indole moiety in satisfactory yields.

Nickel-Catalyzed Direct C (sp3)–H Arylation of Aliphatic Amides with Thiophenes

Nickel-catalyzed heteroarylation of the inactive methyl C(sp(3))-H bond of aliphatic amide with heteroarenes is described. The method takes advantage of chelation assistance by an 8-aminoquinolinyl moiety. The synthetic reaction has good tolerance toward functional groups, and it can be used in the construction of various kinds of alkyl-substituted heteroarenes.

Intramolecular, Site-Selective, Iodine-Mediated, Amination of Unactivated (sp3)C–H Bonds for the Synthesis of Indoline Derivatives

The Iodine-mediated oxidative intramolecular amination of anilines via cleavage of unactivated (sp3)C-H and N-H bonds for the production of indolines is described. This transition-metal-free approach provides a straightforward strategy for producing (sp3)C-N bonds for use in the preferential functionalization of unactivated (sp3)C-H bonds over (sp2)C-H bonds. The reaction could be performed on a gram scale for the synthesis of functionalized indolines.

Ni-Catalyzed Dimerization and Hydroperfluoroarylation of 1,3-Dienes

A nickel-catalyzed three-component coupling reaction between perfluoroarenes and two molecules of a 1,3-diene in the presence of an alkyl Grignard reagent, which acted as a hydride source, provided 3-perfluoroarylated-1,7-octadienes via 1,3-diene dimerization and subsequent perfluoroarylation upon C-F bond cleavage. The reaction proceeded smoothly in a regioselective manner by simply combining NiCl2 and PPh3 as a catalyst and tolerated various functional groups on the perfluoroarenes. When substituted perfluoroarenes were employed, the reaction selectively occurred at the para-position. Mechanistic studies revealed that an anionic Ni complex, generated upon the reaction of Ni(0) with two molecules of a 1,3-diene and an alkyl Grignard reagent, played an important role in the C-C bond forming step with perfluoroarenes. The C-F bond cleavage was found to be a relatively fast step in the catalytic cycle.