A. A. Fagin

Electroluminescent properties of lanthanide pentafluorophenolates

Lanthanide pentafluorophenolates Ln(OC6F5)3(L)x (Ln = Pr, Nd, Sm, Eu, Dy, Ho, Er, Yb; L = 1,10-phenanthroline, 2,2′-bipyridine; x = 1 and 2) are used as emissive layers in organic light emitting devices (OLEDs). Single-layer ITO/Ln(OC6F5)3(L)x/Yb devices reveal no electroluminescence (EL) with the exception of Tb-derivative-based OLEDs. Bilayer ITO/TPD/Ln(OC6F5)3(L)x/Yb samples exhibit a broad band emission peaked at 580 nm assigned to an electroplex at the TPD/complex interface. Besides, the spectra of the devices based on Pr, Nd, Sm, Eu, Er, Tb and Yb derivatives contain the characteristic narrow bands of f–f transitions. Terbium-based bilayer OLEDs exhibit unusual changes in the EL spectra with increasing the applied voltage. The emission color of the devices tunes from orange towards green. The possible nature of the phenomenon is discussed.

Specific chemical behavior of NdII and DyII iodides in reactions with aromatic compounds

Benzene, toluene, tert-butylbenzene, or biphenyl virtually do not react with NdI2 (1) or DyI2 (2) in THF at –20 °C but appreciably accelerate the reactions of these salts with solvents, resulting in LnI3 and intractable mixtures of products of the general composition [LnI(H)(R)(THF)] (R are fragments of the THF molecule). The same effect is induced by the addition of diphenylmercury or tetraphenyltin to solutions of 1 or 2. Phenol easily oxidizes 1 and 2 to give at 0 °C the PhOLnI2(THF)x complexes (x = 3, 4) in 55—95% yields. At –90 °C, iodide 2 is converted into a similar complex PhODyI2(THF)4, whereas 1 gives a mixture of PhONdI2(THF)4, (PhO)2NdI(THF)5, NdI3(THF)3, and [NdI(H)R(THF)]. A plausible pathway of the reactions including the intermediate formation of extremely reactive monovalent lanthanide iodides LnI is discussed.

Metallation of Calix[4]arene with Thulium Diiodide, TmI2(DME)3: Molecular Structure of [(5,11,17,23-Tetra-tert-butyl-25,27-dioxo-26,28- dimethoxycalix[4]arene)thulium(III)iodide(diethyl etherate)]

[(5,11,17,23-Tetra-tert-butyl-25,27-dioxo-26,28-dimethoxycalix[4]arene)thulium(III)-iodide( diethyl etherate)] 1 is obtained by deprotonation of 5,11,17,23-tetra-tert-butyl-25,27- dihydroxy-26,28-dimethoxy-calix[4]arene with 2 equivalents of Tml2(DME)3 in THF.

Study of thermochemical properties of lanthanides pentafluorophenolates with coordination ligands

Saturated vapor pressure of lithium pentafluorophenolate and the lanthanide complexes as a function of temperature has been determined by the Knudsen effusion method. Processing of the pressure data allowed the calculation of thermodynamic parameters of the compounds sublimation. Mass spectra and differential scanning calorimetry data are presented.

Reactions of alkyl compounds of zinc, cadmium, and gallium with dysprosium, neodymium, and thulium diiodides

The ethyl complexes of dysprosium DyI2Et(DME)2 and DyIEt2(DME)2 were synthesized by the reaction of DyI2 with ZnEt2 in dimethoxyethane. The complexes were isolated as pale yellow crystals. According to the X-ray diffraction data, these compounds contain, in addition to DyI2Et(DME)2 and DyIEt2(DME)2, triiodide DyI3(DME)2 (1). The reactions of CdMe2 with NdI2, DyI2, and TmI2 proceed in a similar way and afford methyl iodide complexes of lanthanides. The reaction of GaEt3 with DyI2 gave the ionic complex of trivalent dysprosium [GaEt4]−[DyI2(THF)5]+ (2).