Donor-Functionalized Lanthanide Terphenyl Complexes:  Synthesis and Structural Characterization of 2,6-Di(o-anisol)phenyl Compounds of Ytterbium, Yttrium, and Samarium

Abstract

The syntheses and molecular structures of a number of 2,6-di(o-anisol)phenyl ([double bond]Danip-) -based bis(amide) and bis(alkoxide) compounds of ytterbium, yttrium, and samarium are reported. Additionally, NMR spectroscopic data are reported for the analogous diamagnetic yttrium compounds. Salt metathesis reaction of equimolar amounts of DanipLi and YbCl(3) in tetrahydrofuran at room temperature followed by addition of 2 equiv of KN(SiMe(3))(2) or KN(SiHMe(2))(2) produces DanipYb[N(SiMe(3))(2)](2) (1) and DanipYb[N(SiHMe(2))(2)](2) (2), respectively. The analogous reaction using SmCl(3) and KN(SiHMe(2))(2) produces DanipSm[N(SiHMe(2))(2)](2) (3). Reaction of DanipLi and YbCl(3) in tetrahydrofuran at room temperature followed by addition of 2 equiv of KO(2,6-diisopropylphenyl) produces DanipYb[O(2,6-diisopropylphenyl)](2) (4). Our attempts to also prepare the yttrium analogue of complex 4 yielded single-crystalline material of the tetrahydrofuran adduct DanipY(THF)[O(2,6-diisopropylphenyl)](2) (5). The molecular structures of the complexes 1-4 feature five-coordinate metal atoms and coordination polyhedra which can be described as distorted square-pyramidal rather than trigonal-bipyramidal, with the ipso carbon atom occupying the apical position. On the other hand, the molecular structure of the tetrahydrofuran-solvated yttrium Danip arylalkoxide compound 5 features a six-coordinate metal atom in a distorted trigonal-prismatic coordination environment. In all cases the Danip ligand system adopts the chiral (racemic) d,l form.

The salt-free diamido complexes of lanthanide supported by β-diketiminate: Synthesis, characterization, and their catalytic activity for the polymerization of acrylonitrile and ε-caprolactone

“…However, almost all of the work focused on the complexes with a dianionic ancillary ligand and one amido group. There are only a few papers dealing with the synthesis of well-defined compounds of general formula LLn[NR 2 ] 2 , where L is a monoanionic ancillary ligand [6,7]. The lack in synthesizing these targets may result from the tendency of these types of compounds to undergo complexation by salts [8].…”

A Randomized, Double‐Blind, Placebo‐ and Positive‐Controlled, Three‐Way Crossover Study in Healthy Participants to Investigate the Effect of Savolitinib on the QTc Interval

“…17,18,21,22 Prolongation of the QT interval is associated with increased potential for cardiac proarrhythmias of the torsades de pointes type. 23,24 Consequently, adequate investigation of the safety of new non-antiarrhythmic drugs with systemic bioavailability should include characterization of their potential for effects on the electrocardiogram (ECG), with particular focus on the QTc interval.…”

Synthese von meta‐Terphenyl‐2,2′′‐diolen durch anodische C‐C‐Kreuzkupplungen

“…Besonders interessant sind OCO‐Pincerkomplexe, die strukturell auf meta ‐Terphenyl‐2,2′′‐diolen basieren. Als Metalle können Cr, Mo, W, Ti, Zr, Ta, Sm und Yb genutzt werden. Erfolgreiche Anwendungen der meta ‐Terphenyl‐2,2′′‐diole als Pincerliganden wurde bereits für Sauerstoff‐ und Stickstoffübertragungsreaktionen, Polymerisation von Acetylenen und Olefinen, Alkenisomerisation, Nitren‐ und Carbengruppenübertragungen, O 2 ‐ und C‐H‐Aktivierung, Disulfidreduktionen und aerobe Oxidationen nachgewiesen.…”