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Abstract The reaction of lithium β-diketiminate [{2,6-Me2C6H3N=CMe}2CH]Li with benzophenone in toluene at 25°C affords the coordination complex [{2,6-Me2C6H3N=CMe}2CH]Li(Ph2C=O) (I). New keto-β-diketimine {2,6-Me2C6H3N=C(Me)}2CHC(tert-Bu)=O (II) is synthesized by the reaction of tert-Bu(C=O)Cl with [{2,6-Me2C6H3N=CMe}2CH]Li. The metallation of keto-β-diketimine II with n-butyllithium in THF at 0°C gives lithium keto-β-diketiminate {[{2,6-Me2C6H3N=C(Me)}2CС(tert-Bu)=O]Li(THF)}n (III). The exchange reaction of YCl3 with compound III (molar ratio 1 : 2, THF) affords the yttrium bis(keto-diketiminate) complex [{2,6-Me2C6H3N=C(Me)}2CС(tert-Bu)=O]2Y(μ2-Cl)2L-(THF)2 (IV). The molecular structures of complexes I, III, and IV are determined by X-ray diffraction analysis (CIF files CCDC nos. 2001131 (I), 2001132 (III), and 2001133 (IV)). Complex IV in the crystalline state exists as an ate complex with one LiCl molecule. Complexes I, III, and IV are catalysts of ring-opening polymerization of ε-caprolactone in toluene at 25°С.

Materials based on copolymers of isobornylacrylate (IBA) with methylmethacrylate (MMA) or acrylonitrile (AN) have been synthesized by radical copolymerization using monomeric mixtures with different composition. The copolymer compositions were determined and relative activities of monomers were calculated by different methods. All copolymers have transparency up to 80% in the ultraviolet region. The mechanical and thermophysical properties of the copolymers depend on composition. The best combination of optical transparency and tensile strength is achieved in the copolymers containing 13% and 49% units of IBA (in the case of MMA and AN, respectively. The prospects of application of the copolymers as a matrix for creating photoinduced nanocomposites containing CdS are shown. Using the specially selected compounds of cadmium, materials with new optical properties were obtained by UV irradiation.

The thermal decomposition of cluster Nd3I5(S2)(S2N2)(THF)10 (I) at 50–400°C affords a mixture of products among which tetrahydrofuran (THF), sulfur, diiodine, HI, H2S, CS2, S3N6, S3N5, MeI, thiophene, tetrahydrothiophene, diiodobutane, iodobutene, and NdI3 are identified. The treatment of Ln3I5(S2)(S2N2)(THF)10 (Ln = Nd (I), Dy (II)) with phenanthroline (Phen) in THF at room temperature results in the partial substitution of ТНF to form new complexes Ln3I5(S2)(S2N2)(THF)4(Phen)3. The dissolution of compound I in pyridine gives a pyridine (Py) complex Ln3I5(S2)(S2N2)(THF)3(Py)7. The dissolution of compounds I and II in acetonitrile at 20°C is accompanied by the fast rearrangement and fragmentation of the complexes to form LnI3(MeCN)6, [LnI(S2)(MeCN)], and [LnI(S2N2)(MeCN)]. Complex I in THF does not react with white phosphorus, carbon monoxide, fullerene C60, and chromium hexacarbonyl.

The reaction of NdN and SmN with iodine gave the iodide-nitrides (NdI2)3N(DME)4 and (SmI)3N2(THF)2, which are inert towards sulfur, in contrast to the neodymium and dysprosium iodide-nitrides prepared by the reaction of LnI2 with N2. Reaction of NdN and SmN with C6F5OH and CpH gave the organolanthanide derivatives Ln(C5F5O)3(THF)n (Ln = Nd or Sm) and Cp3Sm with moderate and low yields, respectively. Phenylacetylene and styrene do not react with SmN.

Alkoxides [Ln(OR)3(DME)]2 (R = CH(CF3)2, Ln = Sm (1), Yb (2)), [Ce(OR)3(Phen)]2 (3) (Phen = 1,10-phenanthroline), [Ce(OR′)3(DME)2]2 (R′ = C(CF3)3) (4), {Gd(OR′)3(DME)2} (5), {Ln2[O(CF3)2C–C(CF3)2O]3} (Ln = Ce (6), Gd (7)), {Ce2[O(CF3)2C–C(CF3)2O]3(Phen)2} (8), and {Ce[O(CF3)2C–C(CF3)2O][O(CF3)2–C(CF3)2OH](Phen)2} (9) were synthesized by the reactions of silylamides Ln[N(SiMe3)2]3 with respective fluorinated alcohols. The heterovalent trinuclear complex {Sm2(μ2-OR)3(μ3-OR)2Sm(OR)2(THF)2.5(Et2O)0.5} (10) was obtained by treatment of SmI2(THF)2 with ROK. The reaction of europium(II) and yttrium(III) silylamides with ROH afforded the heterobimetallic alkoxide {Eu2(μ2-OR)3(μ3-OR)2Y(OR)2(DME)2} (11) containing divalent europium. The molecular structures of 1, 2, 3, 9, 10 and 11 were determined by X-ray analysis. All the prepared cerium derivatives as well as the europium–yttrium isopropoxide upon UV excitation exhibited photoluminescence in the regions of 370–425 (for Ce3+) and 485 nm (for Eu2+) which was assigned to 4d→5f transitions.