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The conference Mendeleev 150 was held to join the worldwide celebrations of the 150th Anniversary of the publication of Dmitri I. Mendeleev's Periodic Table of Chemical Elements and the International Year of the Periodic Table proclaimed by the United Nations. The presentations of the invited speakers were published by the Journal of Pure and Applied Chemistry as a special issue. The papers in this issue formed a broad picture of the Periodic Table: the history, the people, the reasoning, the mathematical description of the law, and the efforts to predict and to create any new elements. The highlights of the presentations are briefly introduced in this article as the Preface to the special issue. [ABSTRACT FROM AUTHOR]

GIDRM (www.gidrm.org) in Italy and GERM (germ-asso.fr) in France are the largest non-profit, independent national societies of researchers working in the field of Magnetic Resonance. The conference was organized by the Italian and French societies for Magnetic Resonance, GIDRM (Gruppo Italiano Discussione Risonanze Magnetiche) and GERM (Groupement d'Etudes de Resonance Magnétique) in collaboration with prominent scientific institutions in Milan. Keywords: Italian-French NMR conference EN Italian-French NMR conference 1027 1030 4 10/13/23 20231001 NES 231001 Article note: A collection of invited papers based on presentations at the Italian-French International Conference on Magnetic Resonance, Milan, Italy, 27-30 September 2022. [Extracted from the article]

For this special issue, we collected 8 high quality and breaking research papers on bioinspired and biobased chemistry and materials that were presented in the conference. Keywords: Biobased chemistry and materials; bioinspiration; biomimetics; biomimicry; bionic surfaces and interfaces; biotechnology; molecular architectures; nanobiocatalysts; nanotechnology; NICE 2020; smart technology; sustainable energy EN Biobased chemistry and materials bioinspiration biomimetics biomimicry bionic surfaces and interfaces biotechnology molecular architectures nanobiocatalysts nanotechnology NICE 2020 smart technology sustainable energy 1245 1246 2 11/29/21 20211101 NES 211101 As with the previous editions of NICE Conference, the aim of the 5th International Conference on Bioinspired and Biobased Chemistry & Materials (NICE 2020 Conference) is to provide a venue to experts, researchers, managers, manufacturers and policy makers from different countries and with different scientific backgrounds a place for the exchange of ideas, the open discussion of current research problems and the development of new ideas and collaborations with the aim of sustainable, green, and environmentally friendly solutions to material challenges that will have a lasting impact for generations. Bioinspiration, biomimetics, biotechnology, nanotechnology, NICE 2020, smart technology, Biobased chemistry and materials, bionic surfaces and interfaces, biomimicry, molecular architectures, nanobiocatalysts, sustainable energy. [Extracted from the article]

Keywords: Conference series; solid-state and materials chemistry; SSC 2021 EN Conference series solid-state and materials chemistry SSC 2021 145 146 2 03/11/22 20220201 NES 220201 Article note: A collection of invited papers based on presentations at the 14 th International Conference on Solid State Chemistry (SSC 2021) held in Trencin, Slovakia, June 13-17, 2021. The 14 SP th sp International Conference on Solid State Chemistry was the next of a long row of international conferences founded originally by Prof. Frumar, the renowned Czech scientist and professor, whose scientific school has achieved a worldwide reputation in the field of crystalline and amorphous semiconductors. [Extracted from the article]

Paper based on a presentation at the International Conference on Modern Physical Chemistry for Advanced Materials (MPC '07), 26-30 June 2007, Kharkiv, Ukraine. Other presentations are published in this issue, pp. 1365-1630.In the paper, a report on the rational design of the calixarene receptors bearing ligating, H-donor, H-acceptor fragments at the wide and/or narrow rim of the macrocycle is presented. The calixarenes form supramolecular complexes with various cations, anions, organic molecules, and biomolecules in solution, in the crystalline state and even in the gas phase. The calixarenes or their complexes can be used as materials for radionuclide extraction, construction of chemosensors, and drug design. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the International Conference on Modern Physical Chemistry for Advanced Materials (MPC '07), 26-30 June 2007, Kharkiv, Ukraine. Other presentations are published in this issue, pp. 1365-1630.The key features of the phonon-induced relaxation of electronic excitations in the (7,0) zig-zag carbon nanotube (CNT) and the Pb16Se16 quantum dot (QD) are contrasted using a time-domain ab initio density functional theory (DFT) simulation. Upon excitation from the valence to the conduction band (CB), the electrons and holes nonradiatively decay to the band-edge in both materials. The paper compares the electronic structure, optical spectra, important phonon modes, and decay channels in the CNT and QD. The relaxation is faster in the CNT than in the QD. In the PbSe QD, the electronic energy decays by coupling to low-frequency acoustic modes. The decay is nonexponential, in agreement with non-Lorentzian line-shapes observed in optical experiments. In contrast to the QD, the excitation decay in the CNT occurs primarily via high-frequency optical modes. Even though the holes have a higher density of states (DOS), they relax more slowly than the electrons, due to better coupling to low-frequency vibrations. Further, the expected phonon bottleneck is not observed in the QD, as rationalized by a high density of optically dark states. The same argument applies to the CNT. The computed results agree well with experimentally measured ultrafast relaxation time-scales and provide a unique atomistic picture of the electron-phonon relaxation processes. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the International Conference on Modern Physical Chemistry for Advanced Materials (MPC '07), 26-30 June 2007, Kharkiv, Ukraine. Other presentations are published in this issue, pp. 1365-1630.Quantitative physicochemical analysis (QPCA) enables the determination of the stoichiometric compositions and physicochemical parameters of species in equilibrium systems proceeding from the composition-property dependencies. The paper discusses modifications to the routine QPCA procedures required to characterize properties of reagents fixed on surfaces of silica-organic hybrid materials. The cooperative effects and the energetic heterogeneity of fixed reagents are especially important in this context. It follows that the main peculiarities of silica surfaces chemically modified by aliphatic amines are (a) the pronounced energetic heterogeneity of reagents caused by the non-random surface topography, (b) the decrease of the bacisity of amines induced by their interactions with residual surface silanols, and (c) the expressed sensibility of reactions in the near-surface layer to the state of its hydration. The interaction of grafted organic bases with metal ions results in the preferred formation of bis metal-ligand coordination compounds. Stability constants of complexes are decreased as a consequence of fixation and depend on not only donor but also acceptor ability of a solvent. Also, the denticity of polydentate ligands may decrease as a result of grafting. The changes of protolytic and complexing properties in the case of grafting of weak acids and phosphorus-containing complexons are due to their interactions with other surface groups and the influence of hydration effects in the near-surface layer. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the International Conference on Modern Physical Chemistry for Advanced Materials (MPC '07), 26-30 June 2007, Kharkiv, Ukraine. Other presentations are published in this issue, pp. 1365-1630.The paper reviews ion aggregation in ionic solution in solvents of low and high permittivity. Although higher ion aggregates from 1:1 type electrolytes in low-pemittivity media (εr < 10) are widely accepted, only a few chemists have recognized the higher ion aggregation in the higher-permittivity media. However, we have clarified that the chemical interaction, such as coordination, can operate between simple anions and cations in nonaqueous solvents (20 < εr < 65) of low solvation ability. Acids (HA) and their conjugate base anions (A-) may react with each other to form homoconjugated species, such as A-(HA)2, in acetonitrile or benzonitrile (i.e., solvents possessing poor hydrogen-bonding donor and acceptor abilities). An analytical method of conductivity data for 1:1 electrolytes has been developed and successfully applied to very complicated systems, in which the ion pair (1:1), triple ions (2:1 and 1:2), and the quadrupole (2:2 association) are involved in a solution at the same time. After observing the direct reaction of some anions (e.g., Cl-) and cations (e.g., Li+) toward a certain species, we interpreted comprehensively the salt effects in chemical equilibria, based on distinct chemical interactions and not merely a vague term, "medium effect". The mechanism of salt effects on solvolysis reactions of the SN1 type in organic-aqueous mixed solvents has been elucidated. We discussed that a reaction manner similar to that in nonaqueous solution can take place even in some "aqueous" solution if the huge network of hydrogen-bonding of bulk water (the number of water, nw > ~108) is destroyed due to any spatial barriers (such as ions, molecules, surface) or elevated temperature. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194Stereocontrolled additions of allylic metal reagents to carbonyl compounds constitute one of the most useful classes of transformations in organic synthesis. The recent development of Lewis and Brønsted acid-catalyzed manifolds for the allylboration of carbonyl compounds has opened doors toward an ideal carbonyl allylation methodology using stable and nontoxic allylic boronates as reagents. This paper describes the development of acid-catalyzed allylborations, mechanistic investigations of these new processes, and ongoing efforts toward general catalytic enantioselective allylboration methodologies. The preparation of optically enriched α-substituted allylic boronate reagents is discussed, as well as their applications in Lewis acid-catalyzed additions to afford skeletally diverse products like propionate units, polysubstituted furans, vinylcyclopropanes, and larger ring systems. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194The Reformatsky reaction is a venerable named reaction that was introduced more than 120 years ago. Diastereoselective variants based on the use of chiral auxiliary and enantioselective protocols, based on the employment of stoichiometric amount of chiral ligands, have been successfully applied in organic synthesis during the years. However, a facile and general catalytic enantioselective variant was still a difficult task. Recently, we have established a new general and straightforward methodology for catalytic enantioselective Reformatsky reaction based on different concepts. In this paper, we present our general finding in catalytic enantioselective Reformatsky reaction of ketones, imines, and aldehydes. Our simple methodologies could become benchmark reactions for testing new synthesized chiral ligands for asymmetric transformations. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 12th International Conference on Polymers and Organic Chemistry 2006 (POC'06), 2-7 July 2006, Okazaki, Japan. Other presentations are published in this issue, pp. 1471-1582.In this paper, the synthesis and characterization of molecularly imprinted spherical polymer particulates prepared via precipitation polymerization is described. The effects of the monomer and initiator concentrations and the solvent on the polymerizations were investigated systematically. Polymer microspheres with narrow size distributions and average diameters up to ca. 10 μm were prepared under optimized polymerization conditions. The morphologies of the microspheres were characterized by nitrogen sorption porosimetry and the molecular recognition properties of representative products evaluated in high-performance liquid chromatography (HPLC) mode. Imprinting effects were confirmed by analyzing the relative retentions of the analytes on imprinted and non-imprinted packed HPLC columns. Finally, two different agitation/mixing methods for precipitation polymerizations were compared. It was found that the use of a low-profile roller housed inside a temperature-controlled incubator had advantages over a rotavapor-based system. Overall, this study has served to highlight the attractiveness of precipitation polymerization for the routine production of molecularly imprinted polymers in a well-defined spherical particulate form via an efficient one-step synthetic process. [ABSTRACT FROM AUTHOR]

Keywords: ICS-30 EN ICS-30 939 943 5 09/25/23 20230901 NES 230901 The biennial International Carbohydrate Symposium (ICS) has been organized by the national representatives of the International Carbohydrate Organization (ICO) since 1960, bringing together thousands of worldwide attendees aiming to learn and discuss all aspects related to carbohydrate research and its growing perspectives for future projects. 5: Professor Yasuhiro Kajihara (Osaka University, Japan) receiving the Roy L Whistler International Award in Carbohydrate chemistry from ICO President, Professor Amélia P. Rauter. [Extracted from the article]

Chembl and the PDB are both major resources for open data, but programs to access and analyse these data were covered in the open software section rather than the open data section. Open software All scientists working in chemistry need software tools for accessing, handling, and storing chemical information, or performing molecular modelling and computational chemistry. Open data strand The open data strand of the conference had nine speakers from four countries, exploring many different aspects of open data. [Extracted from the article]

Paper based on a presentation at the International Conference on Modern Physical Chemistry for Advanced Materials (MPC '07), 26-30 June 2007, Kharkiv, Ukraine. Other presentations are published in this issue, pp. 1365-1630.Measurements of the liquid-liquid phase diagrams of solutions of the ionic liquids (ILs) 1-dodecyl-3-methylimidazolium chloride (C12mimCl) in arenes (benzene, toluene, o-xylene, tetraline) and 1-tetradecyl-3-methylimidazolium chloride (C14mimCl) in CCl4 are reported and compared with those of solutions of trihexyl-tetradecyl-phosphonium halides (P666 14Cl, P666 14Br) in hydrocarbons and 1-alkyl-3-methylimidazolium tetrafluoroborates (CnmimBF4) in alcohols and water. The phase diagrams of solutions of tetrapentyl-ammonium bromide (N5555Br) in water and KI in SO2 are also discussed. Except for the KI/SO2 system, which features a lower critical solution point (LCSP), all systems have an upper critical solution point (UCSP) and show corresponding-states behavior. The experimental data are compared with results from simulations and theory concerning the model fluid of charged hard spheres in a dielectric continuum, termed restricted primitive model (RPM). The analysis in terms of of RPM variables shows agreement with the location of the critical point (CP) of the model with noticeable systematic deviations. However, for protic solvents, the CP becomes an LCSP, while in aprotic solvents the CP is a UCSP as expected for Coulomb systems. This indicates that in aprotic solvents, the phase transition is essentially determined by the Coulomb interactions, while in the solutions in protic solvents with hydrogen bonds, both Coulomb and solvophobic interactions are important. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the International Conference on Modern Physical Chemistry for Advanced Materials (MPC '07), 26-30 June 2007, Kharkiv, Ukraine. Other presentations are published in this issue, pp. 1365-1630.Organofunctionalized silsesquioxane polymers obtained in a water-soluble form can be used to coat various substrates such as SiO2, SiO2/Al2O3, Al2O3, cellulose/Al2O3, and graphite or, when obtained in a water-insoluble form, can be used directly. These organofunctionalized silsesquioxanes can also be attached to poly(dimethylsiloxane) (PDMS) polymers. The functional groups constituted by neutral amine groups or cationic groups (pyridinium, 3- and 4-picolinium, or 1,4-diazabicyclo[2.2.2]octane (DABCO), mono- or -dicationic) have relatively high affinity for metal ion in ethanol solutions, as shown by their stability constants. Materials containing attached cationic functional groups have also been efficiently used to immobilize various electroactive species and to construct electrochemical sensors for analytical applications. This work discusses the preparation of silsesquioxane derivatives, their characterization as prepared and when dispersed on several substrates, and comments on some applications of these materials, with an emphasis on the metal adsorption process and manufacture of electrochemical sensors. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the International Conference on Modern Physical Chemistry for Advanced Materials (MPC '07), 26-30 June 2007, Kharkiv, Ukraine. Other presentations are published in this issue, pp. 1365-1630.The advantages of dye-doped polymer matrices over polymers and dyes, separately, are analyzed. The effects of the polymer nature and chemical constitution of organic dyes on the spectral and luminescent properties of these matrices are discussed. The processes of dye aggregation in polymers are characterized, and their influence on the photophysical properties and photochemical stability of dye-doped nonphotoconducting and photoconducting polymers is discussed. The different approaches for the struggle with dye aggregation in polymers are offered. The main paths of energy degradation of electronic excitation in such materials are analyzed. The prospects for the applications of dye-doped polymer materials as passive Q-switches of solid-state lasers, active laser media (ALM), luminescent solar concentrator (LSCs), photovoltaic cells, and electroluminescent (EL) emitters are demonstrated. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the International Conference on Modern Physical Chemistry for Advanced Materials (MPC '07), 26-30 June 2007, Kharkiv, Ukraine. Other presentations are published in this issue, pp. 1365-1630.Cyclodextrins (CDs) attract much attention for industrial applications and academic research. A few experimental methods for determination of the binding constant between CD and a guest molecule were reviewed critically. A hydrophile–hydrophobe matching model for host–guest docking was proposed for estimation of the binding constant and the solution structure of the complex. Rather detailed solution structures of CD complexes were determined by proton NMR spectroscopy, aided by calculations of molecular mechanics and surface areas, and were used to analyze the binding constants. The binding constants of CDs with multi-site guests were analyzed on the basis of their solution structures. The working mechanisms and physicochemical predictions in a few pharmaceutical applications of CDs were proposed on the basis of detailed solution structures and accurate binding constants. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the International Conference on Modern Physical Chemistry for Advanced Materials (MPC '07), 26-30 June 2007, Kharkiv, Ukraine. Other presentations are published in this issue, pp. 1365-1630.The so-called apparent ionization constants of various acids (mainly indicator dyes) in versatile organized solutions are analyzed. Aqueous micellar solutions of colloidal surfactants and related lyophilic colloidal systems display a strong differentiating influence on the acidic strength of indicators located in the dispersed pseudophase, i.e., non-uniform changes of pKa on going from water to the given system. This concept allows the influence of such media on acid-base properties of dissolved reagents to be rationalized. It is demonstrated that the differentiating phenomenon is the main reason for limitation of the common electrostatic model of acid-base interactions, and is the principal hindrance to exact evaluations of the interfacial electrical potentials of ionic micelles by means of acid-base indicators. Salt effects, i.e., the influence of supporting electrolytes on the apparent ionization constants of acid-base indicators in the Stern region of ionic micelles, are considered. These salt effects can be conventionally divided into two kinds, namely, general (normal) and special (specific) effects. While the first type adds up to screening of the surface charge, the second one consists in micellar transitions caused by hydrophobic counterions. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the International Conference on Modern Physical Chemistry for Advanced Materials (MPC ''07), 26-30 June 2007, Kharkiv, Ukraine. Other presentations are published in this issue, pp. 1365-1630.Solutions of the zwitterionic betaine dye 2,6-diphenyl-4-(2,4,6-triphenylpyridinium-1-yl)phenolate (hereinafter called standard betaine dye) and its derivatives are solvatochromic, thermochromic, piezochromic, and halochromic. That is, the position of its longest-wavelength intramolecular charge-transfer (CT) absorption band depends on solvent polarity, solution temperature, external pressure, and the type and concentration of salts (ionophores) added to the betaine dye solution. The outstanding large negative solvatochromism of this standard betaine dye has been used to establish UV/vis spectroscopically a comprehensive set of empirical parameters of solvent polarity, called ET(30) resp. ETN values, now known for many molecular and ionic solvents as well as for a great variety of solvent mixtures. This report describes relevant physicochemical properties of this standard betaine dye as well as the definition and some more recent practical applications of these solvent polarity parameters, derived from the standard betaine dye and its derivatives. In particular, the perichromism of the standard betaine dye can be used to study the polarity of microheterogeneous solutions (e.g., micelles and other organized media), surfaces (e.g., silica, alumina, cellulose), glasses (e.g., sol-gel systems), and solids (e.g., polymers), and for the construction of chemical sensors. As extension to solvatochromism, the more general term perichromism describes UV/vis band shifts of chromophore-containing solutes which are caused not only by changes in the surrounding solvent sphere, but also by their embedding in other surroundings such as micelles, vesicles, glasses, polymers, solids, interfaces, and surfaces. Some representative examples for such extended applications of the perichromic standard betaine dye are given. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the International Conference on Modern Physical Chemistry for Advanced Materials (MPC ''07), 26-30 June 2007, Kharkiv, Ukraine. Other presentations are published in this issue, pp. 1365-1630.Due to population upsurge, pesticides (derivatives of organophosphorus acids included) find widespread use in agriculture. The toxicity and long-term environmental hazard of such compounds require detailed studies on decomposition mechanisms of the pesticides and development of efficient, readily available, and inexpensive systems for their decontamination. A simple and straightforward method for the decomposition of organophosphorus compounds involves their reactions with nucleophiles. Studies on the reactivity of "normal" and α-nucleophiles toward electron-deficient centers allowed us to state a number of basic principles on the nature of the α-effect. One of the most important conclusions is: It is unlikely that the structure variations in the known α-nucleophiles will result in higher reactivity than that of hydroxylamine anion. As a practical matter, the essential disadvantages of decomposition of organophosphorus compounds in water and organic solvents are: (i) instability of active nucleophiles and oxidizing agents, (ii) corrosiveness, and (iii) extremely low solubility of organophosphorus compounds in water. These dictate the strategy of further studies, namely, carrying out the reaction in microorganized media. The first research line involves the development of the functional imidazole-based detergents functionalized with α-nucleophilic fragments. A number of efficient detergents were first synthesized. An examination of the nucleophilicity of the functional fragments in water and in the micellar phase and quantitative assessment of the factors responsible for the micellar effects showed unambiguously that the main cause of the observed accelerations is the substrate concentrating in the micellar pseudophase. The second research line consists of studies on the reactivity of versatile oxidative/nucleophilic systems involving H2O2/activator and polyhalide ion organocomplexes in water, aqueous alcohols, and micelles of cationic detergents. The novel sources of "active" halogen are highly competitive both with conventional hazardous chlorine derivatives and "green" systems involving H2O2/activator. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the International Conference on Modern Physical Chemistry for Advanced Materials (MPC '07), 26-30 June 2007, Kharkiv, Ukraine. Other presentations are published in this issue, pp. 1365-1630.Various decorations, functionalizations, or defects of conjugated benzenoid or graphitic networks are considered, with special attention to the case that the structures are possibly extended in one or two dimensions. This includes various polymers, their end structures, and defects of side groups or vacancies along the chain, strip, or nanotube. This approach further includes various boundary (or edge) structures on semi-infinite graphite, as well as various "quasi-local" defects in what is otherwise two-dimensionally infinite graphite, such defects encompassing vacancy defects, selected substitutional defects, and perhaps even dislocations and disclinations. There are many possible such nanostructures, but property characterization is ultimately desired. Attention is paid to consequent occurrences of defect-localized unpaired (or weakly paired) electrons, as formulated within a resonating valence bond (RVB) framework, especially as regards simple classically appealing theorems or rules. But a further molecular orbital (MO) view is developed. Note is made of associated modifications in the local density of states near the Fermi energy. Consonance of predictions from RVB and MO viewpoints is taken as an indicator of reliable prediction. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the International Conference on Modern Physical Chemistry for Advanced Materials (MPC '07), 26-30 June 2007, Kharkiv, Ukraine. Other presentations are published in this issue, pp. 1365-1630.Detonation nanodiamond (DN) was discovered in 1963, but for several reasons was known only among a small number of scientists until the turn of the century. The most serious cause was the fact that primary nanocarbon particles formed by the "bottom-up method" are in general covalently bound together under high-temperature and -pressure conditions to form large agglutinates, which were difficult to separate by conventional methods. DN was not an exception. A breakthrough led to the isolation of primary particles having the expected size of 4-5 nm by wet-milling with zirconia micro-beads. Thus, long-waited primary particles of DN finally became available in kg quantities in the form of colloidal sol, gel, and readily redispersible flakes. Progress in the development of a new form of the old material is presented. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194The first boryl anion, boryllithium, was synthesized by a reduction of bromoborane precursor using lithium naphthalenide in tetrahydrofuran (THF) solvent at -45 °C. Structural and spectroscopic study revealed an ionic character of B-Li bond. Boryllithium could be utilized as a source of boryl ligand in the transition-metal chemistry. Structural and spectroscopic features of the resulting boryl complexes confirmed the large trans influence of boryl ligand. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194A new hydrosilylative cross-coupling reaction of a variety of alkynes with several alkenes, which is catalyzed by a cationic Pd complex [Pd(η3-C3H5)(cod)]+[PF6]- (cod = 1,5-cyclooctadiene) was studied systematically. The reaction using HSiCl3 as an addend afforded more or less two types of products consisting of four possible derivatives, R1CH=CR2-CHR3-CHR4-SiCl3, which always contained 4-trichlorosilyl-1-butene frameworks, in acceptable combined yields. The coupling pattern was markedly dependent both on the precatalyst in the absence or presence of PPh3 ligand and on the combination of the alkyne and alkene partners employed. A possible catalytic cycle that involves an initial hydropalladation of an alkyne, followed by a facile and specific carbopalladation of an alkene, is proposed. At the same time, the lack of regioselectivity in the latter step is noted. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194A new type of catalytic hydrosilylation of arylalkynes was induced by a 16-electron ruthenium bis(silyl) phosphine complex, resulting in ortho-silylation of the aryl group as well as a hydrogenation of the alkyne CC bond to give an (E)-form of alkene selectively. On the other hand, the same reaction using a related bis(silyl) complex having an η6-toluene ligand instead of the phosphine ligand as a catalyst led to a normal hydrosilylation reaction to afford silylalkene. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194A new type of reagent, γ-methylidene-δ-valerolactones, has been devised, which acts as a four-carbon unit in a Pd-catalyzed cycloaddition reaction through the formation of a 1,4-zwitterionic species. The utility has been demonstrated in the context of stereoselective [4+3] cycloaddition with nitrones to provide highly functionalized 1,2-oxazepines, including the asymmetric variant with high enantioselectivity. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194Selective cross-addition of triisopropylsilylacetylene (TIPSA) to unactivated alkynes is catalyzed by dinuclear and mononuclear palladium complexes supported by a multidentate ligand, N,N'-bis[2-(diphenylphosphino)phenyl]formamidine (dpfamH). While the addition reactions of TIPSA to dialkylacetylenes using palladium catalysts supported by monodentate and bidentate ligands gives dimers of TIPSA as major products, the reactions with the palladium complexes supported by dpfam affords cross-adducts selectively, in which the yields of TIPSA dimers are less than 5 %. The addition of TIPSA to monoalkylacetylenes also gives cross-adducts as major products, although the selectivity and yield are moderate. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194Rhenium complex, [ReBr(CO)3(thf)]2-catalyzed reactions between aromatic imines and either acetylenes or α,β-unsaturated carbonyl compounds gave indene derivatives in good to excellent yields. These reactions proceed via C-H bond activation, insertion of acetylenes or α,β-unsaturated carbonyl compounds, intramolecular nucleophilic cyclization, and reductive elimination. Indene derivatives were also obtained from aromatic ketones and α,β-unsaturated carbonyl compounds in the presence of catalytic amounts of the rhenium complex and p-anisidine. Sequential ruthenium-catalyzed hydroamination of aromatic acetylenes with anilines, and rhenium-catalyzed reactions of the formed aromatic ketimines with α,β-unsaturated carbonyl compounds also provided indene derivatives. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194Zr-mediated equilibrating cyclocarbonylation of a designed triene led with high diastereocontrol to the ABC 6-6-5 tricyclic core of ritterazine N. The 5-5 EF spiroketal side chain of ritterazine N was prepared by equilibrating cyclization of an acyclic keto diol. The two components were coupled, and the D ring was assembled by intramolecular aldol condensation. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194New carbocyclizations that proceed via catalytic metal-vinylidenes are presented. Metal-vinylidene catalytic species, which are easily accessible from terminal alkynes and catalytic amounts of transition-metal complexes, can be involved either in pericyclic reactions or in tandem processes triggered by nucleophilic attack at the electrophilic position of the vinylidene. In both cases, a wide variety of valuable cyclic compounds are easily accessible. Some recent carbocyclizations will be described. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194The oxidative coupling of benzoic acids with alkynes and alkenes effectively proceeds in the presence of a Rh catalyst and an appropriate oxidant to produce the corresponding isocoumarin and phthalide derivatives, respectively. Interestingly, by using an Ir catalyst in place of Rh, the acids and alkynes undergo 1:2 coupling accompanied by decarboxylation to afford naphthalene derivatives exclusively. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194A new protocol for CO gas-free carbonylation, in which aldehydes are used as a substitute for CO, is described. The protocol consists of two Rh-mediated processes; the Rh-mediated decarbonylation of aldehydes, which leads to the formation of Rh carbonyl, and subsequent Rh-catalyzed carbonylative cyclization utilizing the in situ formed Rh carbonyl species. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194Kinetic resolution of planar-chiral 1,1'-diallylferrocene derivatives was realized by Mo- or Ru-catalyzed asymmetric ring-closing metathesis (RCM). The Mo catalyst showed much better performance than the Ru catalyst in the present reactions, and nearly perfect resolution of the racemic ferrocenes was achieved. This is the first example of highly enantioselective metal-catalyzed methods of preparing optically active planar-chiral metallocenes. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194Nickel-catalyzed carbocyanation reaction of alkynes is described. Alkynes undergo aryl- and allylcyanation reaction in the presence of nickel-phosphine catalysts to give a wide range of substituted acrylonitriles in highly stereo-, regio-, and chemoselective manners. Lewis acid cocatalysts, such as AlMe3, AlMe2Cl, and BPh3, are found to promote the arylcyanation significantly. The cooperative catalysis of nickel and Lewis acid also allows the carbocyanation reaction using alkenyl and alkyl cyanides. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194We recently reported the first catalytic diamination of alkenes. This protocol calls for the use of Pd(II) as catalyst in combination with PhI(OAc)2 as terminal oxidant and furnishes the final diamines as cyclic ureas. It consists of an unprecedented two-step reaction of aminopalladation and Csp3-N-bond formation involving a Pd(IV) species. Introduction of Ni(II) catalysts for homogeneous oxidation allows for an efficient diamination with sulfamides, which lead to convenient liberation of the free diamines. In related protocols, the substrate scope of the diamination has been broadened to the formation of cyclic guanidines. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194The reaction of N-benzenesulfonylbenzaldimine with Ni(cod)2 and PCy3 gave the corresponding η2-iminenickel complex quantitatively. Diphenylacetylene reacted with the η2-iminenickel complex to generate five-membered aza-nickelacycle. Insertion of second alkynes into the five-membered aza-nickelacycle led to the formation of the corresponding seven-membered aza-nickelacycles. Heating the solution of the seven-membered aza-nickelacycles induced the reductive elimination to give 1,2-dihydropyridine. In the presence of 10 mol % of Ni(cod)2 and PMetBu2 at 100 °C, the intermolecular [2+2+2] cycloaddition of N-benzenesulfonylbenzaldimine and 2-butyne occurred to give the expected 1,2-dihydropyridine in 87 % yield. In the presence of PCy3, the reaction also proceeded catalytically, however, PMetBu2 gave better results. Less bulky or less basic phosphine, PnBu3 or P(o-tol)3, was not efficient for the reaction. Although Ni(0)-NHC complex was a good catalyst for [2+2+2] cycloaddition of two alkynes and a ketone or an aldehyde, this reaction did not proceed in the presence of an NHC ligand, 1,3-bis-(2,4,6-trimethylphenyl)imidazol-2-ylidene. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194Ti(salan) complexes were found to be efficient catalysts for asymmetric epoxidation with aqueous hydrogen peroxide as the oxidant. In the presence of pH 7.4 phosphate buffer, the reaction of various conjugate olefins proceeded smoothly to afford the corresponding epoxides in high yield with high enantioselectivity, even on a multigram scale. Ti(salan) complexes could be prepared from Ti(OiPr)4 and the corresponding salan ligand and directly used without isolation and purification. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194The gold-catalyzed endo-cycloisomerization of allenes bearing nucleophilic substituents in the α- or β-position opens up a versatile access to various five- and six-membered heterocycles. Key features of these transformations are the high reactivity of the allene in the presence of Lewis-acidic, carbophilic gold(I) or gold(III) catalysts, and the chirality transfer from the allenic axis of chirality to the new stereogenic center in the cyclization product. Recent contributions of our group include the optimization of chirality transfer by using σ-donor ligands to gold, and applications in the total synthesis of natural products, e.g., of the β-carboline alkaloids (-)-isocyclocapitelline and (-)-isochrysotricine. [ABSTRACT FROM AUTHOR]

Paper based on a presentation at the 14th International Symposium on Organometallic Chemistry Directed Towards Organic Synthesis (OMCOS-14), 2-6 August 2007, Nara, Japan. Other presentations are published in this issue, pp. 807-1194Chiral CuF-catalyzed asymmetric allylation of ketones and ketimines is described. Nucleophile activation via transmetallation (allylboronate to allylcopper), which is facilitated by a cocatalyst [La(OiPr)3 or LiOiPr], is key for these reactions. A CuOTf-3KOtBu-DUPHOS complex is a comparably effective catalyst that reduces the required amount of chiral phosphines. [ABSTRACT FROM AUTHOR]