RT info:eu-repo/semantics/article
T1 Ranking Ligands by Their Ability to Ease (C6F5)2NiIIL → Ni0L + (C6F5)2 Coupling versus Hydrolysis: Outstanding Activity of PEWO Ligands
A1 Ponce de León Pintado, Jaime
A1 Gioria, Estefanía
A1 Martínez de Ilarduya Martínez de Ilarduya, Jesús María
A1 Espinet Rubio, Pablo
K1 23 Química
AB The NiII literature complex cis-[Ni(C6F5)2(THF)2] is a synthon of cis-Ni(C6F5)2 that allows us to establish a protocol to measure and compare the ligand effect on the NiII → Ni0 reductive elimination step (coupling), often critical in catalytic processes. Several ligands of different types were submitted to this Ni-meter comparison: bipyridines, chelating diphosphines, monodentate phosphines, PR2(biaryl) phosphines, and PEWO ligands (phosphines with one potentially chelate electron-withdrawing olefin). Extremely different C6F5–C6F5 coupling rates, ranging from totally inactive (producing stable complexes at room temperature) to those inducing almost instantaneous coupling at 25 °C, were found for the different ligands tested. The PR2(biaryl) ligands, very efficient for coupling in Pd, are slow and inefficient in Ni, and the reason for this difference is examined. In contrast, PEWO type ligands are amazingly efficient and provide the lowest coupling barriers ever observed for NiII complexes; they yield up to 96% C6F5–C6F5 coupling in 5 min at 25 °C (the rest is C6F5H) and 100% coupling with no hydrolysis in 8 h at −22 to −53 °C.
PB American Chemical Society
SN 0020-1669
YR 2020
FD 2020
LK http://uvadoc.uva.es/handle/10324/45330
UL http://uvadoc.uva.es/handle/10324/45330
LA eng
NO Inorganic Chemistry, 2020, 59, 24, 18287–18294
NO Producción Científica
DS UVaDOC
RD 26-abr-2024