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This paper presents the results of study of titanium–magnesium catalysts often used in polymerization processes, by photoluminescence spectroscopy (PL) in combination with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The interaction of dibutyl phthalate (DBP) with MgCl2was studied at DBPadded/Mg = 0–1 (mol/mol). The luminescence spectra with excitation at 278 nm and the excitation spectra for main emission bands were recorded. It was shown that DBP adsorbed on magnesium chloride, both in the form of donor–acceptor complexes (D+A–) and in the form of molecular complexes. At DBPadded/Mg +A–complexes occur predominantly; with an increase in DBPadded/Mg, the fraction of molecular complexes increases. Molecular complexes are destroyed during the treatment of the support by TiCl4. In this case, the structure of magnesium chloride is disordered and new coordination–unsaturated sites are formed. This work is a first attempt to apply PL spectroscopy in combination with DRIFTS spectroscopy to study titanium–magnesium Ziegler–Natta catalysts. The application of PL spectroscopy to such systems made it possible to detect interactions within and between donor molecules, which would be particularly challenging to achieve using other spectroscopic methods. Both spectroscopic methods provided crucial information about the existence of two types of complexes on the sample surface which is important for tuning the synthesis procedure of the titanium–magnesium catalysts for olefin polymerization.

Borates M[C6F5BF3] (M = K, Li, Bu4N) react with organolithium compounds, RLi (R = Me, Bu, Ph), in 1,2-dimethoxyethane or diglyme to give M[4-RC6F4BF3] and M[2-RC6F4BF3]. When R is Me or Bu, the nucleophilic substitution of the fluorine atom at the para position to boron is the predominant route. When R = Ph, the ratio M[4-RC6F4BF3]/M[2-RC6F4BF3] is ca. 1:1. Substitution of the fluorine atom at the ortho position to boron is solely caused by the coordination of RLi via the lithium atom with the fluorine atoms of the BF3 group. This differs from the previously reported substitution in K[C6F5BF3] by O- and N-nucleophiles that did not produce K[2-NuC6F4BF3].

A new synthetic platform for ionic liquids (ILs) with specific properties was suggested based on the polyfluorophenyltrifluoroborate anions, Q[4-XC6F4BF3] (X = F, RO). Convenient preparative approaches to these ILs including the ones with chiral counteranions were developed. The dependence of physicochemical properties of ILs on the nature of substituents in the fluorinated ring was studied.

The paper presents comprehensive studies on the process of the copper-containing active sites formation which are needed for the “direct” synthesis of trialkoxysilanes at the interaction of alcohols with a silicon-based contact mass. These sites are formed during a two step consequent pretreatment of the initial contact mass by hydrogen and argon flow. The so activated samples of contact mass were investigated using HAADF-STEM EDX, EXAFS, XPS and XRD methods. The role of each step of the activation is disclosed. Participation of topochemical and heterogeneous chemical reactions as well as processes of diffusion and sorption–desorption during the active sites formation was found. Based on the retrieved data a new mechanism for the formation of the active sites on the surface of silicon during the activation of the contact mass for the “direct” synthesis of trialkoxysilanes is suggested.

Small differences in the reactivity of weakly nucleophilic potassium aryltrifluoroborates are revealed in the silver-assisted Pd-catalyzed cross-coupling of K[4-RC6F4BF3] (R = H, Bu, MeO, EtO, PrO, iPrO, BuO, t-BuO, CH2=CHCH2O, PhCH2O, PhCH2CH2O, PhO, F, pyrazol-1-yl, pyrrol-1-yl, and indol-1-yl) with ArX (4-BrC6H4CH3, 4-IC6H4F and 3-IC6H4F). An assumed role of silver(I) compounds AgmY (Y = O, NO3, SO4, BF4, F) consists in polarization of the Pd–X bond in neutral complex ArPdLnX with the generation of the related transition state or formation of [ArPdLn][XAgmY] with a highly electrophilic cation and subsequent transmetallation with the weakly nucleophilic borate. Efficiency of AgmY as a polarizing agent decreases in order Ag2O > AgNO3 ≈ Ag2SO4 > Ag[BF4] > AgF. No clear correlation between the reactivity of K[4-RC6F4BF3] and substituent electron parameters, σI and σR°, of the aryl group 4-RC6F4 was found.

A method for nanostructured cuprous chloride preparation by reductive thermolysis of a CuCl2⋅2H2O and Cu(OH)2 mixture in glycerol has been developed. The resultant CuCl was characterized with infrared spectroscopy, X-ray photoelectron spectroscopy, EXAFS spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The prepared samples of CuCl demonstrated high catalytic activity in the “direct synthesis” of triethoxysilane.

Potassium polyfluoroaryltrifluoroborates, K[Ar F BF 3 ] (Ar F = C 6 F 5 , HC 6 F 4 , MeC 6 F 4 , 4-MeOC 6 F 4 , 4-indol-1-ylC 6 F 4 , 4-imidazol-1-ylC 6 F 4 , 4-pyrazol-1-ylC 6 F 4 , 2,4,6-C 6 F 3 H 2 and 4-tetrafluoropyridyl), and K[(C 6 F 5 ) 2 BF 2 ] undergo hydrodeboration to Ar F H in aliphatic alcohols at elevated temperature. At the same conditions, borates K[3,4,5-C 6 F 3 H 2 BF 3 ], K[4-FC 6 H 4 BF 3 ] and K[C 6 H 5 BF 3 ] remain intact. The presence of base (Et 3 N, K 2 CO 3 and NaOMe) retards or prevents conversion of K[C 6 F 5 BF 3 ]. Attempted hydrodeboration of K[C 6 F 5 BF 3 ] in MeCN failed.

The influence of the ligand nature on catalytic activity of palladium catalysts for cross-coupling of weakly nucleophilic potassium pentafluorophenyltrifluoroborate, which imitates the behavior of electron-deficient organoboron reagents, with aryl halides, ArHal (Hal=Br, Cl) was studied. The activity of the catalysts generated in situ from Pd(OAc)2 and appropriate phosphorous containing ligands and the reaction selectivity was found to depend on the nature of bulky phosphines used as ligands. As a result, conditions for involving the electron-deficient organoboron reagent—potassium pentafluorophenyltrifluoroborate—in the palladium-catalyzed cross-coupling with aryl bromides and aryl chlorides were identified. It was demonstrated that the chosen conditions are appropriate for the reaction of K[C6F5BF3] with benzyl chloride and benzyl bromide deriving pentafluorophenylarylmethanes, C6F5CH2Ar.

Nucleophilic substitution of fluorine atom in K[C6F5BF3] with alkali metal azol-1-ides in polar aprotic solvent (DMF, DMSO) at 60–130 °C gives potassium 4-(azol-1-yl)-2,3,5,6-tetrafluorophenyltrifluoroborates, K[4-AzC6F4BF3] (AzH = pyrrole, pyrazole, imidazole, indole, and benzimidazole). Unexpectedly, diethylamine and morpholine do not react with K[C6F5BF3] under the same conditions while pentafluorobenzene and R2NC6F4H form at 150 °C. Reaction of K[C6F5BF3] with Na[NR2] in diglyme or DMSO proceeds similar way. The assumed reason is the relatively low nucleophilicity of both secondary amines and alkali metal dialkylamides which results in destructive by-reaction with K[C6F5BF3] rather than in its aminodefluorination. This is confirmed by the competitive nucleophilic aminodefluorination of a model substrate, C6F5Ph, with sodium indolide/sodium morpholinide.

A new route to potassium polyfluoroaryltrifluoroborates, K[4-ROC6F4BF3], consisting in the nucleophilic alkoxydefluorination of K[C6F5BF3] with MOR (M = K, Na) in a polar aprotic solvent is suggested. Reaction of K[C6F5BF3] with KO-t-Bu proceeds smoothly at 25 °C in DME, but the attempted alkoxydefluorination of K[C6F5BF3] with other NaOR at 30 °C in DME failed. A series of K[4-ROC6F4BF3] (R = Me, Et, Pr, i-Pr, Bu, PhCH2) is prepared using the corresponding sodium alkoxides in DMF at 130 °C in 80–90% isolated yield. Salt K[4-CH2 CHCH2OC6F4BF3] is prepared at 100 °C whereas at 130 °C formation of 2,3,5,6-C6F4HOCH2CH CH2 occurs. Salt K[4-PhOC6F4BF3] is obtained in 82% yield using KOPh (2 equivalents) in DMSO at 130 °C.

The influence of the ligand nature on catalytic activity of palladium catalysts for cross-coupling of weakly nucleophilic potassium pentafluorophenyltrifluoroborate, which imitates the behavior of electron-deficient organoboron reagents, with aryl halides, ArHal (Hal=Br, Cl) was studied. The activity of the catalysts generated in situ from Pd(OAc)2 and appropriate phosphorous containing ligands and the reaction selectivity was found to depend on the nature of bulky phosphines used as ligands. As a result, conditions for involving the electron-deficient organoboron reagent—potassium pentafluorophenyltrifluoroborate—in the palladium-catalyzed cross-coupling with aryl bromides and aryl chlorides were identified. It was demonstrated that the chosen conditions are appropriate for the reaction of K[C6F5BF3] with benzyl chloride and benzyl bromide deriving pentafluorophenylarylmethanes, C6F5CH2Ar.