4-Ferrocenylphenol

The title compound, [Fe(C5H5)(C11H9O)], is of inter­est as a precursor to the synthesis of cheap ferrocene-based liquid crystals. The –OH substituent only results in weak C—H⋯O weak inter­actions between one of cyclo­penta­dienyl (Cp) ring H atoms and the O atom of a neighbouring mol­ecule with a distance of 3.308 (3) Å between the donor and acceptor atoms. The inter­planar angle between the Cp and benzene rings is 13.0 (4)°. There are also weak O—H⋯π and C—H⋯π inter­actions involving the unsubstituted Cp and the benzene ring, respectively

Theoretical models of nonlinear effects in two-component cooperative supramolecular copolymerizations

The understanding of multi-component mixtures of self-assembling molecules under thermodynamic equilibrium can only be advanced by a combined experimental and theoretical approach. In such systems, small differences in association energy between the various components can be significantly amplified at the supramolecular level via intricate nonlinear effects. Here we report a theoretical investigation of two-component, self-assembling systems in order to rationalize chiral amplification in cooperative supramolecular copolymerizations. Unlike previous models based on theories developed for covalent polymers, the models presented here take into account the equilibrium between the monomer pool and supramolecular polymers, and the cooperative growth of the latter. Using two distinct methodologies, that is, solving mass-balance equations and stochastic simulation, we show that monomer exchange accounts for numerous unexplained observations in chiral amplification in supramolecular copolymerization. In analogy with asymmetric catalysis, amplification of chirality in supramolecular polymers results in an asymmetric depletion of the enantiomerically related monomer pool

Основи маркетингу (для студентів)

Серія навчально-методичних посібників містить розширені матеріали, що необхідні для розуміння та ведення підприємницької діяльності, розуміння механізмів пошуку та ідентифікації можливостей для бізнесу, визначенні питань управління підприємницькою діяльністю, правових основ підприємництва, соціальної відповідальності бізнесу та його маркетингової діяльності. Призначено для студентів ВНЗ І-II рівня акредитації економічних, управлінських та інженерних спеціальностей, підприємців початківців та фахівців практиків

Mechanism and Enantioselectivity in Palladium-Catalyzed Conjugate Addition of Arylboronic Acids to β‑Substituted Cyclic Enones: Insights from Computation and Experiment

Enantioselective conjugate additions of arylboronic acids to β-substituted cyclic enones have been previously reported from our laboratories. Air- and moisture-tolerant conditions were achieved with a catalyst derived in situ from palladium(II) trifluoroacetate and the chiral ligand (S)-t-BuPyOx. We now report a combined experimental and computational investigation on the mechanism, the nature of the active catalyst, the origins of the enantioselectivity, and the stereoelectronic effects of the ligand and the substrates of this transformation. Enantioselectivity is controlled primarily by steric repulsions between the t-Bu group of the chiral ligand and the α-methylene hydrogens of the enone substrate in the enantiodetermining carbopalladation step. Computations indicate that the reaction occurs via formation of a cationic arylpalladium(II) species, and subsequent carbopalladation of the enone olefin forms the key carbon–carbon bond. Studies of nonlinear effects and stoichiometric and catalytic reactions of isolated (PyOx)Pd(Ph)I complexes show that a monomeric arylpalladium–ligand complex is the active species in the selectivity-determining step. The addition of water and ammonium hexafluorophosphate synergistically increases the rate of the reaction, corroborating the hypothesis that a cationic palladium species is involved in the reaction pathway. These additives also allow the reaction to be performed at 40 °C and facilitate an expanded substrate scope

Unusual complexes formed by the early lanthanides with 2,6-bis(5,6-dialkyl-1,2,4-triazin-3-yl)-pyridines

International audienc

Lanthanide(III) complexes of a highly efficient actinide(III) extracting agent 2,6-bis(5,6-dipropyl-1,2,4-triazin-3-yl)pyridine

International audienc

Complexation of Lanthanide(III) and Actinide(III) Catins with Tridentate Nitrogen-Donor Ligands: A Luminescence and Spectrophotometric Study

RADIOCHThe complexation of Lanthanide(III) (lanthanum, europium, and lutenium) and americium(III) by four Nitrogen-Donor Ligands was investigated in homogeneous methanol/water solutions by using structural and thermodynamic approaches. The stoichiometry and inner-sphere hydration state of the europium complexes formed were determined by time-resolved laser-induced fluorimetry. The stability constants and in some cases the thermodynamic parameters were measured by ultraviolet-visible spectrophotometry and the van't Hoff method. The comparison of the stability constants of americium complexes with lanthanide complexes shows better stability for the actinide species. The strong affinity for these ligands towards Am ${+3} is confirmed by the formation of higher complexes, especially in the case of 2,6(5,6-dimethyl-1,2,4-triazin-3-yl)-pyridine (MeBTP), the only ligand able to form a 1:3 complex. The influence of the solvent composition on the complexation thermodynamics highlights the effect of the solvent reorganization on the reaction