RT info:eu-repo/semantics/article
T1 Opposite effects of added AsPh3 reveal a drastic mechanistic switch in RhI/AuI transmetalations via Rh–Au bonded intermediates
A1 Peñas de Frutos, Marconi Nicolás
A1 Bartolomé Albistegui, María del Camino
A1 García Melchor, Max
A1 Espinet Rubio, Pablo
K1 Energy
K1 Gold
K1 Ligands
K1 Metals
K1 Transmetalation
K1 2210 Química Física
AB In contrast with the previously reported decelerating effect of added L (L = AsPh3) on the Rf/Pf exchange reaction between [Au(Pf)L] and trans-[Rh(Rf)(CO)L2] (Pf = C6F5; Rf = C6F3Cl2-3,5), the Rf/Cl exchange between [AuClL] and trans-[Rh(Rf)(CO)L2] is accelerated by addition of an excess of L. By combining experimental data and microkinetic modeling, with DFT calculations, the unexpected existence of two cooperative Rf/Cl exchange mechanisms is demonstrated. The opposite kinetic effects of L addition, from negative in the Rf/Pf exchange process, opposing L dissociation in an octahedral rhodium intermediate, to positive in the Rf/Cl exchange, opening an L-catalyzed alternative pathway via tricoordinate gold intermediates, explain the Janus effect of AsPh3. The three transmetalation pathways involve a metal redox-insertion step with accessible activation barrier, producing intermediates with Rh–Au bonds. Whereas our previously reported Rf/Pf exchange implied Rh(I) oxidation by Au(I), the Rf/Cl exchange mechanism involves Au(I) oxidation by Rh(I). Further support is provided by NBO studies, which reveal remarkable electronic donations from the oxidized metal in each case forging the M–M′ covalent interaction in the intermediates yielded by the redox-insertion step.
PB American Chemical Society
SN 0020-1669
YR 2025
FD 2025
LK https://uvadoc.uva.es/handle/10324/79560
UL https://uvadoc.uva.es/handle/10324/79560
LA eng
NO Inorganic Chemistry, 2025, vol. 64, n. 27, p. 13729-13739
NO Producción Científica
DS UVaDOC
RD 09-dic-2025