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C56H60N8O4Zr, monoclinic, C2/c (no. 15), a = 24.665(4) Å, b = 18.836(3) Å, c = 25.425(6) Å, β = 114.364(4)°, V = 10760(4) Å3, Z = 8, Rgt(F) = 0.0550, wRref(F2) = 0.1239, T = 296(2) K.

Seven examples of chlorozirconium N‐[(N,N‐dimethylamino)dimethylsilyl]‐2‐pyridylaminates, mononuclear monoligand Zr[(RC5H4N)NSiMe2NMe2]Cl3LiCl(Et2O)2 (R = 4‐Me, Zr1; R = 5‐Me, Zr2; R = 5‐Cl, Zr3), chloro‐bridged dinuclear diligand [Zr{(RC5H4N)NSiMe2NMe2}Cl3]2 (R = 5‐Cl, Zr4; R = 4‐Cl, Zr5), and mononuclear triligand Zr[(RC5H4N)NSiMe2NMe2]3Cl (R = 6‐Me, Zr6; R = H, Zr7), have been prepared by the individual reactions of zirconium tetrachloride with the corresponding lithium N‐[(N,N‐dimethylamino)dimethylsilyl]‐2‐pyridylaminates of (RC5H4N)NHSiMe2NMe2 (R = 4‐Me, 1a; 5‐Me, 1b; 5‐Cl, 1c; 4‐Cl, 1d; 6‐Me, 1e; H, 1f), respectively. Besides seven coordination around zirconium core, Zr1–Zr5 adopt a distorted pentagonal bipyramid geometry with the ligand acting as a monoanionic η2:η1‐tridentate fashion; Zr6–Zr7 present capped trigonal prism geometry with the ligand as η2‐coordination with a pendant N (CH3)2 free. Extensively, the reactions of FeCl2 with lithiated (RC5H4N)NHSiMe2NMe2 (R = 4‐Me, 1a; 5‐Cl, 1c; 6‐Me, 1e) afford the corresponding dimeric complexes (R = 4‐Me, Fe1; 5‐Cl, Fe2; 6‐Me, Fe3), in which Fe1 and Fe2 exhibit C2 symmetry with each iron unit as a distorted trigonal bipyramidal geometry, while Fe3 specially possesses a centrosymmetric hour‐glass‐shaped core with each iron center as a distorted tetrahedral geometry. Upon activation with methylaluminoxane (MAO), zirconium complexes exhibit moderate to good activities toward ethylene polymerization and produce the polyethylenes with high molecular weight and broad dispersity. [ABSTRACT FROM AUTHOR]

C56H60N8O4Zr, monoclinic, C2/c (no. 15), a = 24.665(4) Å, b = 18.836(3) Å, c = 25.425(6) Å, β = 114.364(4)°, V = 10760(4) Å3, Z = 8, Rgt(F) = 0.0550, wRref(F2) = 0.1239, T = 296(2) K. [ABSTRACT FROM AUTHOR]

The trichlorozirconium η-hydrazonides (R=H, A; R=CH, B) were synthesized through the finely controlled stoichiometrical reactions of anhydrous zirconium tetrachloride with the lithium salt of either 1-(furan-2-ylmethylene)-2-phenylhydrazonide or 1-(furan-2-ylethylidene)-2-phenyl hydrazonide in the solvent tetrahydrofuran (THF), respectively. These complexes were highly sensitive to air and moisture due to solely using less bulky ligand of hydrazonides. The molecular structures of the title complexes, determined by means of single crystal X-ray diffraction, were found to be the distorted pentagonal bipyramid geometry around zirconium atom, with three chlorides and the hydrazonato ligand acting as the η-coordination mode as well as two incorporated THF molecules. Upon activation with either methylaluminoxane (MAO) or modified methylaluminoxane (MMAO), both complexes A and B exhibited catalytic activities toward ethylene polymerization, producing polyethylenes with ultra-high molecular weights. [ABSTRACT FROM AUTHOR]

The two title crystalline compounds, viz. meso-bis{η5-1-[1-(dimethylamino)ethenyl]-3-(trimethylsilyl)cyclopentadienyl}iron(II), [Fe(C12H20NSi)2], (II), and meso-bis{η5-1-[1-(dimethylamino)ethenyl]-3-(trimethylsilyl)cyclopentadienyl}cobalt(II), [Co(C12H20NSi)2], (III), were obtained by the reaction of lithium 1-[1-(dimethylamino)ethenyl]-3-(trimethylsilyl)cyclopentadienide with FeCl2 and CoCl2, respectively. For (II), the trimethylsilyl- and dimethylaminoethenyl-substituted cyclopentadienyl (Cp) rings present a nearly eclipsed conformation, and the two pairs of trimethylsilyl and dimethylaminoethenyl substituents on the Cp rings are arranged in an interlocked fashion. In the case of (III), the same substituted Cp rings are perfectly staggered leading to a crystallographically centrosymmetric molecular structure, and the two trimethylsilyl and two dimethylaminoethenyl substituents are oriented in opposite directions, respectively, with the trimethylsilyl group of one Cp ring and the dimethylaminoethenyl group of the other Cp ring arranged more closely than in (II). [ABSTRACT FROM AUTHOR]

A novel cholesterol-containing amphiphile was designed and prepared in the study, which is a room-temperature ionic liquid crystal over a broad temperature range with pronounced chiroptical properties. Four types of inorganic polyoxometalates (PMs) with different numbers of charges were encapsulated by the chiral amphiphile. The incorporation of chiral organic cations triggers achiral PMs in the complexes to show induced chirality through intermolecular interactions, as demonstrated by circular dichroism spectroscopy. The electrostatic encapsulation with mesomorphic promoters provides the inorganic PMs with liquid crystalline behavior, characterized by differential scanning calorimetry, polarized optical microscopy, and X-ray diffraction. The strategy applied herein represents a unique example of liquid crystalline PM complexes with optical activity., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)