Direct observation of two-electron Ag(I)/Ag(III) redox cycles in coupling catalysis

Text Complet
Direct-observation.pdf closed access
Sol·licita còpia a l'autor de l'article
En omplir aquest formulari esteu demanant una còpia de l'article dipositat al repositori institucional (DUGiDocs) al seu autor o a l'autor principal de l'article. Serà el mateix autor qui decideixi lliurar una còpia del document a qui ho sol•liciti si ho creu convenient. En tot cas, la Biblioteca de la UdG no intervé en aquest procés ja que no està autoritzada a facilitar articles quan aquests són d'accés restringit.
Compartir
Silver is extensively used in homogeneous catalysis for organic synthesis owing to its Lewis acidity, and as a powerful one-electron oxidant. However, two-electron redox catalytic cycles, which are most common in noble metal organometallic reactivity, have never been considered. Here we show that a Ag(I)/Ag(III) catalytic cycle is operative in model C–O and C–C cross-coupling reactions. An aryl-Ag(III) species is unequivocally identified as an intermediate in the catalytic cycle and we provide direct evidence of aryl halide oxidative addition and C–N, C–O, C–S, C–C and C–halide bond-forming reductive elimination steps at monometallic silver centres. We anticipate our study as the starting point for expanding Ag(I)/ Ag(III) redox chemistry into new methodologies for organic synthesis, resembling well-known copper or palladium cross-coupling catalysis. Furthermore, findings described herein provide unique fundamental mechanistic understanding on Ag-catalysed cross-coupling reactions and dismiss the generally accepted conception that silver redox chemistry can only arise from one-electron processes ​
​Tots els drets reservats