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Ytterbium reacts with 1 ,2-bis[(2,6-diisopropylphenyl)imino]-acenaphthene (1, dpp-Bian) in 1 ,2-dimethoxyethane (DME) to give complex (dpp-Bian)Yb(DME)2 (2). Oxidation of 2 with an 0.5 mol equivalent of dibromostilbene affords dimeric compound [(dpp-Bian)Yb(DME)(μ-Br)]2 (3). Molecular structures of 2 and 3 were determined by single-crystal X-ray analysis. In complex 3 in a DME solution, a temperature-dependent reversible intramolecular electron transfer between the ligand and the metal takes place. [ABSTRACT FROM AUTHOR]

A gallium(I) carbenoid derived from redox-active diimine 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-bian) in complexes with molybdenum may serve either as a neutral [(dpp-bian)Ga:] or an anionic [(dpp-bian)Ga:]- two-electron donor depending on the electronic state of the transition metal. [ABSTRACT FROM AUTHOR]

Abstract: The thiolate complexes of rare earth metals Ln(SR)3 (La, HSR=2-mercaptothiazoline (1); La, HSR=2-mercaptobenzoxazole (2); Y, La, Sm, Eu, Tb, Gd, Er, Tm, HSR=2-mercaptobenzothiazole (3)) were synthesized in 84–97% yield by the reactions of silylamides Ln[N(SiMe3)2]3 with respective thiols. The products were characterized by elemental analysis, IR and UV/Vis spectroscopy. The structures of 3(Eu) and 3(Er) were determined by single-crystal X-ray diffraction. All obtained compounds revealed efficient luminescence in the region 400–550nm at 293K assigned to the ligands emission. Besides, the luminescent spectra of thiolates 3 at 77K displayed the phosphorescent band of the ligand at 550nm and in the cases of 3(Eu) and 3(Tb) the sets of emissions bands characteristic for Eu3+ and Tb3+ ions. [Copyright &y& Elsevier]

Abstract: It was found that the lanthanide diiodides LnI2 (1) (Ln=Nd, Sm, Eu, Dy, Tm, Yb) are dissolved in isopropylamine (IPA) without redox transformations. Stability of the formed solutions decreases in a row Eu≈Yb>Sm>Tm>Dy>Nd. Removing of a solvent in vacuum leaves complexes LnI2(IPA) x (2) (Nd, x =5; Sm, Eu, Dy, Tm, Yb, x =4) as crystalline colored solids. Stability of 2-Nd,Dy,Tm is higher than that of known THF or DME coordinated salts. Divalent state of metal in the products is confirmed by data of UV–Vis spectroscopy, magnetic measurements and their chemical behavior. Structure of 2-Eu and 2-Tm was established by X-ray diffraction analysis. Oxidation of 2-Nd,Dy in IPA affords amine-amides (Pr i NH)Ln(IPA) y (3) (Nd, y =4; Dy, x =3). n-Propylamine also dissolves the iodides 1-Sm,Eu,Dy,Tm,Yb but stability of the solutions is significantly lower. 1-Nd vigorously reacts with Pr n NH2 even at −30°C which hampers the formation of the solution. [Copyright &y& Elsevier]

The complexes of La, Ce, Nd, Sm, Eu, Tb and Yb with benzoxazolyl-phenolate, benzothiazolyl-phenolate, benzoxazolyl-naphtholate, benzothiazolyl-naphtholate and 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione ligands were treated with n,γ-irradiation upon a sustained (45 h, absorbed dose of 120 krad, flux of neutrons 5·1013 n/cm2) and a pulse mode (3 ms, absorbed dose of 130 krad, flux of neutrons 3.6·1013 n/cm2). It was found that main characteristics of the compounds (shape of substance, color, IR absorption and photoluminescent spectra) have not changed. With an example of cerium complex [Ce(OON)3]2 it was revealed that the molecular structure of compounds after strong pulse irradiation also does not changed. However, computer simulations of neutron exposure on the same complexes showed significant shift of metal atoms and ligands. Possible reasons for the detected discrepancy between experimental and calculated data are discussed. [ABSTRACT FROM AUTHOR]