This paper describes a new palladium-catalyzed method for C-H activation/carbon-carbon bond formation with hypervalent iodine arylating agents. This transformation has been applied to a variety of arene and benzylic substrates containing different directing groups (pyridines, quinolines, oxazolidinones, and amides) and proceeds with high levels of regiocontrol. Mechanistic experiments provide preliminary evidence in support of an unusual mechanism for this transformation involving a Pd(II)/Pd(IV) catalytic cycle.

This communication describes a new palladium-catalyzed method for the oxygenation of unactivated sp3 C-H bonds. A wide variety of alkane substrates containing readily available oxime and/or pyridine directing groups are oxidized with extremely high levels of chemo-, regio-, and in some cases diastereoselectivity. The substrate scope of these reactions is discussed, and the high selectivities are rationalized on the basis of the requirements of putative palladium alkyl intermediates.

This paper describes a detailed investigation of factors controlling the dominance of a directing group in Pd-catalyzed ligand-directed arene acetoxylation. Mechanistic studies, involving reaction kinetics, Hammett analysis, kinetic isotope effect experiments, and the kinetic order in various reagents, have been conducted for a series of different substrates. Initial rates studies of substrates bearing different directing groups showed that these transformations are accelerated by the use of electron withdrawing directing groups. However, in contrast, under conditions where two different directing groups are in competition with one another in the same reaction flask, substrates with electron donating directing groups react preferentially. These results are discussed in the context of the proposed mechanism for Pd-catalyzed arene acetoxylation.

[reaction: see text] This paper describes the application of peroxide-based oxidants in the Pd(OAc)(2)-catalyzed acetoxylation and etherification of arene and alkane C-H bonds. Oxone in acetic acid and/or methanol proved particularly effective, and these transformations were applied to a wide variety of substrates.

Resolute in the face of elimination: Substituted 3‐aminotetrahydrofurans were prepared in good yield and with modest to high diastereoselectivity by the Pd‐catalyzed reaction shown in the scheme (Phth=phthaloyl). Mechanistic studies indicate a PdII/PdIV catalytic cycle involving cis aminopalladation and intramolecular CO bond‐forming reductive elimination with retention of configuration at the carbon atom.