Exceptionally fast carbon–carbon bond reductive elimination from gold(III)

Reductive elimination of carbon-carbon (C-C) bonds occurs in numerous metal-catalyzed reactions. This process is well documented for a variety of transition metal complexes. However, C-C bond reductive elimination from a limited number of Au(III) complexes has been shown to be a slow and prohibitive process, generally requiring elevated temperature. Herein, we show that oxidation of a series of mono- and bimetallic Au(I) aryl complexes at low temperature generates observable Au(III) and Au(II) intermediates. We also show that aryl-aryl bond reductive elimination from these oxidized species is not only among the fastest observed for any transition metal, but is also mechanistically distinct from previously studied alkyl-alkyl and aryl-alkyl reductive eliminations from Au(III)

Alkane Functionalization via Electrophilic Activation

Electrophilic activation, which may be defined as the substitution of a transition metal center for a proton to generate a new metal–carbon bond, is the basis of a number of promising approaches to selective catalytic functionalization of alkanes. The field was introduced by the groundbreaking chemistry exhibited by aqueous chloroplatinum complexes, reported by Shilov in the early 1970s. Since then the field has expanded greatly, and electrophilic alkane activation has been demonstrated using a wide variety of species. These include ligand-supported platinum complexes; complexes of additional late transition metals, most commonly palladium but also iridium, gold and others; and even post-transition metals such as mercury. That body of work is surveyed here, with particular emphasis on mechanistic understanding, examples of actual functionalization at sp^3-hybridized C–H bonds in alkanes and related compounds, and assessment of the further development that will be needed for practical applications