RT info:eu-repo/semantics/article T1 Coordinatively Unsaturated [RhCp*Rf2] (Cp* = C5Me5; Rf = C6F3Cl2-3,5), General Precursor to Cp*-Diaryl and Cp*-Halo-Aryl RhIII Complexes. Observing and Testing the Effect of Cp* as Electronic Buffer A1 Peñas de Frutos, Marconi Nicolás A1 Bartolomé Albistegui, María del Camino A1 Espinet Rubio, Pablo K1 Química organometálica K1 Organometallic chemistry AB The pentacoordinated [RhCp*Rf2] (Rf = C6F3Cl2-3,5) and the octahedral (μ-Cl)2[RhCp*Rf]2, obtained by stoichiometric rearrangement with (μ-Cl)2[RhCp*Cl]2, are general precursors of [RhCp*RfXL] (X = Rf, Cl; L = ligand) complexes, which were studied by NMR (L dissociation and fluxional processes) and X-ray diffraction (structural effects affecting the Rh–Cp* distances) techniques. The Rh–Cp*centroid distances decrease markedly for identical L in the order [RhCp*Rf2L] > [RhCp*RfClL] > [RhCp*Cl2L] and are further influenced regularly within each family by the trans influence of L (longer distances for higher trans influence of L). The structural effects observed reveal a remarkable capability of Cp* to act as an electron-density buffer, which attenuates the Rh electron density variations induced by the substituents in front of Cp* by releasing toward Rh or polarizing toward Cp*, on demand, the electron density of the Rh–Cp* bonds. This buffer effect explains the easy L dissociation from [RhCp*Rf2L] and the accessibility to formally 16e pentacoordinated [RhCp*Rf2]. PB American Chemical Society SN 0276-7333 YR 2018 FD 2018 LK http://uvadoc.uva.es/handle/10324/32632 UL http://uvadoc.uva.es/handle/10324/32632 LA eng NO Organometallics, 2018, 37 (20), pp 3533–3542 NO Producción Científica DS UVaDOC RD 28-abr-2024