96620-51-8Relevant articles and documents
Cationic Dirhodium Complexes Bridged by 2-Phosphinopyridines Having an Exquisitely Positioned Axial Shielding Group: A Molecular Design for Enhancing the Catalytic Activity of the Dirhodium Core
Ohnishi, Ryuhei,Ohta, Hidetoshi,Mori, Shigeki,Hayashi, Minoru
, p. 2678 - 2690 (2021/07/31)
This report describes a strategy to create highly electrophilic dirhodium catalysts. The electrophilicity of lantern-Type dirhodium complexes is generally decreased by the coordination of a ligand to the axial site, which often causes a reduction in the catalytic activity. We designed and synthesized a series of cationic dirhodium complexes bridged by 2-diarylphosphinopyridines having a bulky 2,4,6-Triisopropylphenyl (Tip) group that can prevent the attack of external molecules to the closest axial site. Theoretical calculations indicated that the Tip group weakly interacts with the axial site but hardly reduces the electrophilicity of the dirhodium core. The complexes served as excellent catalyst precursors for the dehydrogenative silylation of alcohols using hydrosilanes under mild conditions and a low metal loading, producing the silyl ethers in higher yields in comparison to conventional dirhodium complexes.
Synthesis and evaluation of ligands with mixed amide and phosphonate, phosphinoxide, and phosphonothioate sites for An(III)/Ln(III) extraction
Iqbal, Mudassir,Struijk, Richard G.,Huskens, Jurriaan,Sypula, Michal,Wilden, Andreas,Modolo, Giuseppe,Verboom, Willem
, p. 2048 - 2059 (2013/02/23)
Various organophosphorus ligands with a combination of different donor sites were synthesized and evaluated by solvent extraction studies for the complexation of Am(iii)/Eu(iii). Among the ligands with a glycolamide backbone, those with mixed amide and P=O donor sites and a central oxygen or nitrogen atom showed a reasonable extraction of Am(iii) and Eu(iii). Ligands with a central oxygen atom exhibited selectivity towards Eu(iii), and those with a central nitrogen atom towards Am(iii). Ligands with P=S donor sites and a glycolamide backbone did not show any reasonable extraction. Amongst the ligands with a malonamide backbone, high extraction efficiency was observed for the ligand with electron-rich substituents on phosphorus, however, with almost no discrimination between Am(iii) and Eu(iii). The extraction efficiency of different ligands towards Eu(iii) was confirmed by microcalorimetry.
