Synthesis and reactivity of carbonylbis(triphenylphosphine)rhodium(I) complexes of water and weakly coordinating anions

Promoting effect of ionic liquids on ligand substitution reactions

“…Addition of AgSbF 6 to a toluene or CH 2 Cl 2 solution of Rh(CO)(PPh 3 ) 2 Cl in the presence of an excess amount of the corresponding pyridine gave good yields of the cationic pyridine complexes (Eq. (3)) [37]. Molar absorptivity values () for the cationic complexes (2) were the same within experimental error (±0.1 · 10 3 M À1 cm À1 ) independent of the identity of the pyridine ligand.…”

“…This step plays key roles in important catalytic cycles such as hydrogenation, Ziegler-Natta-type polymerization, hydrocarboxylation, and Heck coupling. Herein we report our initial results on the effect of IL solvents on the displacement of anionic ligands at a d 8 Rh(I) center by pyridine derivatives [37], which serves as a model for this type of catalytic step (Eq. (1)).…”

New carboalkoxybis(triphenylphosphine)palladium(II) cationic complexes: Synthesis, characterization, reactivity and role in the catalytic hydrocarboalkoxylation of ethene. X-ray structure of trans-[Pd(COOMe)(TsO)(PPh3)2]·2CHCl3

“…Complexes (Ia-c and Ie) show two sharp bands of low intensity; complex If shows one band of low intensity at 3637 cm −1 and an unresolved broad absorption centered at 3142 cm −1 ; complexes Id and Ig show a broad unresolved band centered at 3220 and at 3144 cm −1 , respectively. Those at lower frequency suggest the presence of a hydrogen-bond between water and TsO − , with consequent lowering of O-H [31][32][33]. The absorptions in the ranges of 1273-1222, and 1014-1007 cm −1 are identified as some of the characteristic bands of the anionic -SO 3 group [34][35][36][37][38].…”

Influence of electrostatic repulsive force and electron-withdrawing effect in ionic diphosphine on regioselectivity of rhodium-catalyzed hydroformylation of 1-octene

“…In situ IR spectroscopy has been used as an important technique for the research of hydroformylation of olefins because of the valuable information on the active Rh-H species formed under the actual reaction conditions [29][30][31][32][33][34][35][36][37][38]. The dramatic promoting effects of 1 on the selectivity to linear nonanal and the increased TOF at relatively higher temperature of 120 o C evoked us to explore the formation and stability of the active Rh-H species or other rhodium-CO complex intermediates in charge of chemselectivity and/or regioselectivity.…”