Christopher J. Teskey

Ruthenium-Catalyzed meta-Selective C-H Bromination.

The first example of a transition-metal-catalyzed, meta-selective C–H bromination procedure is reported. In the presence of catalytic [{Ru(p-cymene)Cl2}2], tetrabutylammonium tribromide can be used to functionalize the meta C–H bond of 2-phenylpyridine derivatives, thus affording difficult to access products which are highly predisposed to further derivatization. We demonstrate this utility with one-pot bromination/arylation and bromination/alkenylation procedures to deliver meta-arylated and meta-alkenylated products, respectively, in a single step.

Domino N-/C-Arylation via In Situ Generation of a Directing Group: Atom-Efficient Arylation Using Diaryliodonium Salts

Both aryl components of diaryliodonium salts can be used in a domino one-pot reaction via in situ generation of a directing group. A number of heterocycles undergo N-arylation which is followed by ruthenium-catalyzed C-arylation. Notably the reaction extends well to unsymmetrical diaryliodonium salts with a number of highly selective examples shown.

Ruthenium-Catalyzed meta-Carboxylation

The meta-carboxylation of arenes containing pyridine and other azine-directing groups is reported. Using carbon tetrabromide as the C1 source, ruthenium(III) trichloride catalysis enables functionalization of the arene meta-C-H position, affording carboxy methyl ester products after in situ reaction with methanol.

Cross-Dehydrogenative-Coupling of Alkoxybenzenes with Toluenes: Copper(II) Halide Mediated Tandem Halo/Benzylation of Arenes

A cross-dehydrogenative-coupling of alkoxybenzenes and toluenes with concomitant halogenation is reported. Conditions employed were the use of stoichiometric copper halide salts and dialkylperoxides to afford a range of bromoalkoxydi- and triarylmethanes. Preliminary mechanistic studies suggest that the in situ production of haloarenes (or dihaloarenes) followed by a copper-mediated coupling of a benzylic radical is operational.

Correction to: Regioselective synthesis of pyridines by redox alkylation of pyridine N-oxides with malonates

The original version of this article unfortunately contained mistakes. In section “General procedure” some numbers were missing. The corrected text is given below.

Regioselective synthesis of pyridines by redox alkylation of pyridine N-oxides with malonates

A regioselective synthesis of pyridines by the addition of malonate anions to pyridine N-oxide derivatives, which have been activated by trifluoromethanesulfonic anhydride, is reported. The reaction selectively affords either 2- or 4-substituted pyridines in good yields.Graphical abstract

Chemoselective Intermolecular Cross-Enolate-Type Coupling of Amides

A new approach for the synthesis of 1,4-dicarbonyl compounds is reported. Chemoselective activation of amide carbonyl functionality and subsequent umpolung viaN-oxide addition generates an electrophilic enolonium species that can be coupled with a wide range of nucleophilic enolates. The method conveys broad functional group tolerance on both components, does not suffer from formation of homocoupling byproducts and avoids the use of transition metal catalysts.