Rhodium(III)-catalyzed C4-amidation of indole-oximes with dioxazolones C-H activation.

A novel method for the Rh(iii)-catalyzed oxime-directed C-H amidation of indoles with dioxazolones has been developed. This strategy provides an exclusive site selectivity and the directing group can be easily removed. This transformation features a wide substrate scope, good functional group tolerance and excellent yields, and may serve as a significant tool to construct structurally diverse indole derivatives for the screening of potential pharmaceuticals in the future.

Ruthenium(II)-Catalyzed α-Fluoroalkenylation of Oxime Ethers with -Difluorostyrenes C-H Activation and C-F Cleavage.

A novel route for ruthenium(II)-catalyzed α-fluoroalkenylation of oxime ethers with -difluorostyrenes C-H activation and C-F cleavage has been developed for the first time. Notably, the alkenyl units of products exhibit exclusive Z-configuration. This reaction features a broad substrate scope and good functional group tolerance.

C-H Borylation of Diphenylamines through Adamantane-1-carbonyl Auxiliary by BBr.

A method for -C-H borylation of diphenylamines using BBr as the boron source has been reported. The noncatalytic adamantane-1-carbonyl directed reaction exhibited site exclusivity and good functional group tolerance. Generally, the borylation occurred at the more electron-rich aromatic ring and the borylated products could be converted to various useful intermediates.

2-Amino-5,6-difluorophenyl-1-pyrazole-Directed Pd Catalysis: Arylation of Unactivated β-C(sp)-H Bonds.

Palladium-catalyzed arylation of unactivated β-C(sp)-H bonds in carboxylic acid derivatives with aryl iodides is described for the first time using 2-amino-5,6-difluorophenyl-1-pyrazole as an efficient and readily removable directing group. Two fluoro groups are installed at the 5- and 6-position of the anilino moiety in 2-aminophenyl-1-pyrazole, clearly enhancing the directing ability of the auxiliary. In addition, the protocol employs Cu(OAc)/AgPO (1.

Tandem C-C/C-N Formation via Palladium-Catalyzed C-H Activation/Styrenation and Sequential Annulation of O-Methylketoxime with Styrenes.

A novel route for tandem C-C/C-N formation via palladium-catalyzed C-H activation/styrenation and annulation of O-methylketoxime with styrenes to synthesize benzothienopyridines and benzofuropyridines has been developed. Furthermore, the intermolecular alkenylation of the ketoxime with acrylates produces 3-alkenyl O-methylketoximes in good to excellent yields. The method features mild reaction conditions and good functional group tolerance, providing a direct approach for the preparation of fused heterocycles.

Palladium-catalyzed direct mono-aroylation of O-arylmethyl and aryl-substituted acetoxime ethers.

An efficient palladium-catalyzed ortho-aroylation of O-arylmethyl and aryl-substituted acetoxime ethers has been developed; this method has high mono-site selectivity and does not require exogenous ligands. Under the direction of a simple exo-acetoxime auxiliary, a broad scope of masked arylmethyl alcohols and phenols as well as various aromatic aldehydes are compatible with this transformation, which probably follows a mechanistic pathway involving a six- or five-membered exo-cyclopalladated intermediate. The strategy can be expediently adopted to prepare synthetically valuable 1H-benzo[d][1,2]oxazines and benzo[d]isoxazoles.