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A series of ortho-substituted 2,2′-aryl-1,1′-binaphthalenes were prepared via Negishi arylation of 2,2′-diiodo-1,1′-binaphthalene in good to high yields (65–95%) as an equilibrium mixtures of up to three atropisomers (unlike,unlike, like,unlike, and like,like). Thermodynamic stability parameters of the atropisomers were evaluated from VT NMR spectra by regression analysis. The DFT parameters calculated using CAM-B3LYP functional comprising solvent permittivity were, apart from the toluene solution, which was expected to interact with the aromatic solute, in qualitative agreement with the experimental values. In the case of the ditolyl derivative, the population of the atropisomers was confirmed by CD spectroscopy via comparison with the population-weighted averaged spectrum computed using the M06 functional. X-ray structure analyses of particular atropisomers of the dianisyl, dianilinyl, and dinaphthyl derivatives are also presented and discussed.

Chiral ferrocene phosphane–carbenes are good ligands for the copper-catalyzed 1,4-addition of Grignard reagents to various Michael acceptors. The products were obtained in high enantiomeric purity (up to e.r. = 95:5) and excellent regioselectivity (r.r. = 99:1). These ligands are also useful for domino conjugate addition followed by enolate trapping with imine and aldehyde.

A series of [5]ferrocenophane diphosphane ligands were used in Pd-catalyzed allylic substitution reactions. With a symmetrical substrate, 1,3-diphenylpropenyl acetate, enantioselectivities between 70% and 94% ee were observed. Several non-symmetrically substituted allylic substrates were also used. Depending on the substituents of the non-symmetrical allylic substrates, various degrees of regioselectivity (from 1:1 to 100:0) and enantioselectivity (from 0% to 96% ee) were observed. Tentative catalytically active complexes were studied by DFT computational methods.

The compositions of regioisomeric mixtures of tricarbonyliron complexes of 2-methyltropone (1a,b), 3-methyltropone (2a,b) and 2,6-dimethyltropone (3a,b) are studied and compared with the results of ab initio computations. The structures, frontier orbitals, and population analysis are evaluated by means of density functional theory. The thermodynamic and kinetic parameters of regioisomerizations are determined using dynamic 1H NMR technique. The influence of methyl-substituent(s) on the equilibrium ratio of regioisomers resulting from the haptotropic rearrangement is discussed. Significant differences in the reactivity of C-protonized methyl- and dimethyl-substituted tricarbonyl(tropone)iron complexes 4–6 in nucleophilic additions and corresponding O-trimethylsilylated complexes 7–9 in [3+2] cycloadditions are explained in terms of electronic and steric effects of the methyl group(s). Various hydroazulenone cycloadducts of tricarbonyl(η4-2,6-dimethyltropone)iron 3a,b have been prepared by stereoselective [3+2] cycloaddition with Fp-reagents 12–14 and characterized. Formerly proposed mechanism of [3+2] cycloaddition was approved.

Solvent-free reactions of 2- and 3-halopyridines with PPh 3 , PBu 3 , and PCy 3 were studied under conventional heating, as well as under microwave irradiation. No difference was observed in the reaction course between classical and microwave reactions. 2-Bromopyridine gave quantitative yields of 2-pyridyltriphenylphosphonium bromide within few minutes at 190°C. Equimolar amounts of some inorganic salts (LiPF 6 , LiOTf, LiBr, NaPF 6 , KPF 6 ) were necessary for the reactions of the other 2-halopyridines. 3-Halopyridines did not react with PPh 3 even in the presence of LiPF 6 . Their reactions with PCy 3 in the presence of LiPF 6 resulted in the quantitative formation of dicyclohexylphosphine oxide.

The kinetic and thermodynamic parameters for regioisomerisation of 2-methyl- and 2,6-dimethyl-derivatives of tricarbonyl[η 4 -tropone]iron complexes have been studied by 1 H NMR spectrometry over a range of 40 °C. Regioisomerisation of these complexes proceeds by an intramolecular first-order process and results in the almost complete conversion of the less stable complexes ( 4 , 8 ) to more stable regioisomers ( 1 , 5 ). The activation energies and half lifes for the conversion ( 4 → 1 ) and ( 8 → 5 ) were found to be Δ G # =92 kJ mol −1 ; τ 1/2 =12.8 h, and Δ G # =107 kJ mol −1 ; τ 1/2 =26.8 h, respectively, at 23 °C. Complex 1 reacts with (1R,2S,5R)-menthol in sulphuric acid solution, followed by neutralisation with sodium carbonate to give a separable mixture of diastereomeric tricarbonyl[(2,3,4,5-η)-(1R ′ ,2S ′ ,5R ′ )-6-menthyloxy-2-methyltropone]iron complexes, 9 and 10 . The corresponding dimethylated complex 5 fails to react under these conditions.

The diastereoselectivity of [3+2] cycloaddition of tricarbonyl[(4,5,6,7-η)-2-methyltropone]iron (2) with an E,Z isomeric mixture of η1-(crotyl)Fp (4E/4Z) [Fp: C5H5Fe(CO)2 or CpFe(CO)2] has been studied. By this cyclopentaanulation, four stereogenic centres are formed. The reaction occurs regioselectively and stereoselectively. The relative configurations of the cycloadducts 5a, 5b and 5c were assigned on the basis of 2D and NOE NMR experiments. A mechanism for the stereoselective [3+2] cycloaddition has been proposed. The selectivity of the cycloaddition depends on the difference in steric discrimination approaches of the η1-(crotyl)Fp 4E/4Z to the tricarbonyl[(3,4,5,6,7-η)-1-trimethylsilyloxy-2-methyltropylium]iron 3 (repulsion of the methyl and methylene groups of 4 and the planar skeleton of 3) and also upon the isomeric structure (E or Z) of the η1-(crotyl)Fp reactant. The geometrical isomerism of the reagent (4E/4Z) is preserved in the products 5a–c.

In this study, we demonstrate the synthesis of the [Al13O4(OH)24(H2O)12]7+ Keggin e-Al13 ion by a mechanochemical reaction between [Al(H2O)6]Cl3 and (NH4)2CO3 reactants. Five grams of the starting mixture corresponding to a molar ratio of (NH4)2CO3/[Al(H2O)6]Cl3 = 0.45:2, 1:2, 1.5:2, 2:2, 2.25:2, 2.55:2 and 3:2 was milled for 5 min. The existence of e-Al13 was observed at molar ratios of (NH4)2CO3/[Al(H2O)6]Cl3 = 2:2 and higher. Our results show that more than 50% mass of Al from a starting [Al(H2O)6]Cl3 was bonded to the polymeric [Al13O4(OH)24(H2O)12]7+ ionic form at a molar ratio of 2.55:2.

Herein we report the synthesis and characterization of a linear,two-coordinate Pt(II) ketimide complex, Pt(N=CtBu2)2 (1), formed via thereaction of PtCl2(1,5-COD) with 2 equiv of Li(N=CtBu2). Also generated inthe reaction is the bimetallic complex [(tBu2C=N)Pt(μ-N,C-N=C(tBu)C(Me)2CH2)Pt(N=CtBu2)] (2). Both complexes 1 and 2 have beencharacterized by NMR spectroscopy and X-raycrystallography. Notably,complex 1 exhibits short Pt−N distances (av. Pt−N = 1.817 Å) and anunusually deshielded 195Pt chemicalshift (δPt = −629 ppm) with a large1J(195Pt,14N) coupling constant (537 Hz).These data, in combination with adetailed density functional theory electronic structure analysis, reveal thepresence of highly covalent Pt=N multiple bonds formed by a combination ofσ-donation, π-donation, and π-backdonation.