Epoxy resins cured with ionic liquids as novel supports for metal complex catalysts

In this work, the application of an epoxy resin cured with ammonium ionic liquids as a support for palladium complex catalyst is reported. Supports based on epoxy resin were obtained as a result of the use of ionic liquids: didecyldimethylammonium tetrafluoroborate [d₂m₂am][BF₄], 1-methyltheobromine tetrafluoroborate [mthb][BF₄], didecyldimethylammonium theobrominate [d₂m₂am][thb], didecyldimethylammonium theophyllinate [d₂m₂am][thp] as cross-linking agents. The characterization of polymeric supports and heterogenized palladium catalysts has involved research methods like time-of-flight secondary ion mass spectrometry (TOF-SIMS), infrared spectroscopy (IR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS). The activity and stability during long-term use of the investigated catalytic systems were tested in a model Heck reaction. The influence of the type of ILs used as epoxy hardeners on the catalytic properties of epoxy-supported palladium catalysts is discussed.     

Thermal characterization of new complexes of Zn(II) and Cd(II) with some bipyridine isomers and propionates

New mixed ligand complexes of the following stoichiometric formulae: M(2-bpy)₂(RCOO)₂·nH₂O, M(4-bpy)(RCOO)₂·H₂O and M(2,4’-bpy)₂(RCOO)₂·H₂O (where M(II)=Zn, Cd; 2-bpy=2,2’-bipyridine, 4-bpy=4,4′-bipyridine, 2,4′-bpy=2,4′-bipyridine; R=C₂H₅; n=2 or 4) were prepared in pure solid-state. These complexes were characterized by chemical and elemental analysis, IR and conductivity studies. Thermal behaviour of compounds was studied by means of DTA, DTG, TG techniques under static conditions in air. The final products of pyrolysis of Cd(II) and Zn(II) compounds were metal oxides MO. A coupled TG/MS system was used to analyse of principal volatile products of thermal decomposition or fragmentation of Zn(4-bpy)(RCOO)2·H2O under dynamic air and argon atmosphere. The principal species correspond to: C⁺, CH⁺, CH₃ ⁺, C₂H₂ ⁺, HCN⁺, C₂H₅ ⁺ or CHO⁺, CH₂O⁺ or NO⁺, CO₂ ⁺, ¹³C¹⁶O₂ ⁺ and ¹²C¹⁶O¹⁸O⁺ and others; additionally CO⁺ in argon atmosphere.     

Crystal structure of compounds [Ln(H2O)8]3+·4CCl3COO?·4H2O·2(4-bpy)·(4-bpyH)+(Ln(III) = Gd, Tb, Er, AND Tm)

Novel compounds of Gd(III), Tb(III), Er(III), and Tm(III) with 4,4??-bipyridine (4-bpy) and trichloroacetates are prepared. The title compounds are isomorphic and isostructural in the solid state. All atoms in the studied compound lie in general positions of the Cc space group. The coordination polyhedra around central atoms can be described as bicapped trigonal prisms slightly disordered towards a square antiprism. All 4-bpy molecules are located in the outer coordination sphere together with four trichloroacetate anions and four water molecules. One of the nitrogen atoms of one 4-bpy is protonated due to stoichiometry.     

Synthesis, thermal behavior, and other properties of Y(III) and La(III) complexes with 4,4′-bipyridine and trichloro- or dibromoacetates

New Y(III) and La(III) complexes with 4-bpy (4,4??-bipyridine) and trichloro- or dibromoacetates with the formulae: Y(4-bpy)₂(CCl₃COO)₃·H₂O I, La(4-bpy)_1.5(CCl₃COO)₃·2H₂O II, Y(4-bpy)_1.5(CHBr₂COO)₃·3H₂O III, and La(4-bpy)(CHBr₂COO)₃·H₂O IV were prepared and characterized by chemical, elemental analysis, and IR spectroscopy. Conductivity studies (in methanol, dimethyloformamide, and dimethylsulfoxide) were also described. They are small, crystalline substances. The way of metal?Cligand coordination was discussed. The thermal properties of complexes in the solid state were studied by TG-DTG techniques under dynamic flowing air atmosphere. TG-FTIR system was used to analyze principal volatile thermal decomposition and fragmentation products evolved during pyrolysis in dynamic flowing argon atmosphere for La(III) compounds.