bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and Reactions of Quinoxaline Derivatives
Authors: Badr Mahmoud Zarif Amin , El-Naggar Galal Moustafa , El-Sherief Hassan Ahmad Hassan , Mahgoub Safar Ahmed 
Published: July 2006

Abstract
Reaction of 3-methyl-2(1H)quinoxalinone (1) with alkyl, benzyl, and arenesulfonyl halides in the presence of K2CO3 in dry acetone gave 1-substituted 3-methyl-2(1H)-quinoxalinones (2a–g). However 1 reacts with benzoyl chloride under the same conditions to give 3-methyl-2-quinoxalinyl benzoate, while it reacts with P2S5 in dry pyridine to give 3-methyl-2(1H)quinoxalinethione (4). Treatment of 4 with methy iodide in the presence of K2CO3 in dry acetone gave 2-methyl-3-(methylthio)quinoxaline but not 1,3-dimethyl-2(1H)-quinoxalinethione which has been obtained from 2a and P2S5 in dry pyridine. Treatment of 4 with benzyl bromide and/or p-nitrobenzyl bromide in the presence of K2CO3 in dry acetone gave 2-benzylthio and 2-(p-nitrobenzylthio)-3-methylquinoxalines. Syntheses of 1-methyl-3-(substituted styryl)-2(1H)-quinoxalinone (8a–m) were achieved by condensation of 2a with aromatic aldehydes. Addition of thiophenols and mercaptoacetic acid to 8 gives 1-methyl-3-[2-(substituted phenylthio)ethyl]-2(1H)-quinoxalinones and 1-methyl-3-[2-(substituted phenyl)-2-(carboxymethylthio)ethyl]-2(1H)-quinoxalinones respectively. 1,3-Dimethyl-2(1H)-quinoxalinone (2a) condensed with ketones in the presence of ZnCl2 to give 1-methyl-3-[2-(substituted phenyl)-1-alkenyl]-2(1H)-quinoxalinones. 1-Methyl-3-(substituted styryl)-2(1H)-quinoxalinethiones were produced by refluxing a mixture of 8 with P2S5 in dry pyridine.
Asymmetric Reduction of Schiff’s Bases with Lithium Aluminium Hydride–Monosaccharide Complexes to Give Optically Active Secondary Amines
Authors: Landor Stephen R , Sonola Olatunji O , Tatchell Austin R 
Published: July 2006

Abstract
The asymmetric reduction of selected Schiff ’s bases (ketimines) with the lithium aluminium hydride–monosaccharide complexes derived from 3-O-benzyl-1,2-O-cyclohexylidene-α-d-glucofuranose gives optically active secondary amines. The absolute configuration of N-(1-phenylethyl)aniline was assigned as S by N-phenylation of S-(−)-1-phenylethylamine and hence all the levo-rotatory secondary amines obtained by this asymmetric reduction are assigned the S-configuration.
Carbon Monoxide Absorption by Aqueous CuCl–MgCl2 Absorbent
Authors: Katsumoto Masayuki , Kanehori Keiichi , Kamiguchi Taiji 
Published: July 2006

Abstract
Carbon monoxide absorption characteristics of an aqueous CuCl–MgCl2 solution system are clarified. A CuCl 3.7 mol/l–MgCl2 4.7 mol/l solution is found to absorb 2.2 mol of CO per liter at 30°C and Pco=2×104 Pa. This is 8 times greater than a CuCl 3.2 mol/l–HCl 8.2 mol/l solution and 16 times greater than a CuCl 4.8 mol/l–KCl 5.9 mol/l solution. The CO absorption of the concentrated aqueous solution of CuCl–MgCl2 is accompanied with fine particle precipitation. This precipitate, which consists of CO, Cu+, Mg2+, Cl−, and H2O, is estimated to be CO·CuMgCl3·nH2O. The complex completely releases CO at 70°C or above. Chloride ion influence on the formation of CO·CuMgCl3·nH2O is discussed.
Reactions of 2-Diazo-1,2-Diphenylethanone and Diphenyldiazomethane with Ketohydrazones
Authors: Singh Girija Shankar , Singh Surendra Bahadur , Mehrotra Kailash Nath 
Published: July 2006

Abstract
The reactions of 2-diazo-1,2-diphenylethanone (1) with ketohydrazones (3a–c) in equimolecular ratio yield (diphenylacetyl)hydrazones (4a–c) of the corresponding benzophenones which on further treatment with 1 in equimolecular ratio leads to 1-diphenylacetylazo-1,1,3,3-tetraaryl-2-propanones (5a–c). The product 5a is also obtained in the reaction of 1 with benzophenone hydrazone (3a) in 2 : 1 molecular ratio. The bis(acetylacetonato)copper(II)-catalyzed reaction of 1 and also of diphenyldiazomethane (2) with ketohydrazones (3) affords ketazines (6). The mechanistic route for the formation of products is discussed.
Equilibria in the Aqueous Ternary System Containing Na+, CH3CO2−, and P2O74− between 38 and 85°C
Authors: Wada Takahiro , Yokotani Fumiko , Matsuo Yoshihiro 
Published: July 2006

Abstract
The ternary system CH3CO2Na–Na4P2O7–H2O was investigated between 38 and 85°C. No double salt occurs in this temperature range. The saturated CH3CO2Na solutions can contain only small amount of Na4P2O7. The CH3CO2Na solutions have a very strong dehydrating influence on Na4P2O7·10H2O. So, the lowest formation temperature of anhydrous Na4P2O7 is about 47°C.
A Direct Evidence for the Overestimation of Acidity Incidental to the Benesi Method
Authors: Mishima Shozi , Nakajima Tsuyoshi 
Published: July 2006

Abstract
Acid strength distributions of silica-alumina, silica-magnesia, and their mixtures were measured by the Benesi method. Overestimation of acidity has been demonstrated by the measurement that the acidity in the range H0≤−3.0 for the mixtures is larger than the value expected from additivity.
Optical Resolution of Dl-Alanine by Formation of Ternary Copper(II) Complexes with l-Isoleucine
Authors: Shiraiwa Tadashi , Fukuoka Hirofumi , Yoshida Masahiro , Kurokawa Hidemoto 
Published: July 2006

Abstract
A ternary complex, (d-alaninato)(l-isoleucinato)copper(II) (abbreviated as [Cu(d-ala)(l-ile)]), was crystallized selectively at 0°C from an aqueous solution containing Dl-alanine (Dl-Ala), l-isoleucine (l-Ile), and copper(II) acetate monohydrate (Cu(OAc)2·H2O) in the molar ratio of 1:1:1.
Syntheses and Circular Dichroism Studies of Oligopeptides Having Tri- or Tetra-l-prolyl Sequences
Authors: Sato Kazuki , Tanaka Masato , Hayase Tetsuo 
Published: July 2006

Abstract
CD spectra of many oligopeptides having tri- or tetra-l-prolyl sequences showed that a penta- or hexapeptide having a tetra-l-prolyl sequence took poly(l-proline) II helix irrespective of amino acid residues at N- or C-terminal of a l-prolyl cluster and that as to a size of the cluster, tri-l-prolyl sequence was enough to form the helix, when glycine was used as substituent.
Chromatographic Resolution of Racemic Compounds Containing Phosphorus or Sulfur Atom as Chiral Center
Authors: Okamoto Yoshio , Honda Shiro , Hatada Koichi , Okamoto Ichiro , Toga Yuzo , Kobayashi Shiro 
Published: July 2006

Abstract
Racemic compounds containing a phosphorus or a sulfur atom as a chiral center were resolved by high-performance liquid chromatography on optically active (+)-poly(triphenylmethyl methacrylate). The resolved compounds include insecticides such as O-ethyl O-(4-nitrophenyl) phenylphosphonothionate (EPN), O-(4-cyanophenyl)-O-ethyl phenylphosphonothionate (cyanofenfos), and 2-methoxy-4H-1,3,2-benzo-dioxaphosphorin 2-sulfide (salithion).
The Solubilization Site of Methylferrocene in Cationic Micelles
Authors: Hoshino Katsuyoshi , Saji Tetsuo , Ohsawa Yasuhiko , Aoyagui Shigeru 
Published: July 2006

Abstract
The voltammetry of methylferrocene (MeFC) in a dodecyltrimethylammonium bromide micellar solution leads to the conclusion that most MeFC molecules reside in the micelle phase. They are located within the hydrophobic core where water cannot reach, judging from our finding that oxygen decomposes MeFC in the presence of water, but otherwise does not.
Translational Energy Distribution of the Excited Hydrogen Atom (n=4) Produced in Electron-Benzene Collisions
Authors: Kawazumi Hirofumi , Kurawaki Junichi , Ogawa Teiichiro 
Published: July 2006

Abstract
Line shapes of the Balmer-β line of H* produced in dissociative excitation of C6H6 were precisely measured. The translational energy distributions of H* (n=4) have two peaks at about 1 and 4 eV, and their relative intensity depends on incident electron energy.
Selective Mono- and Dibromination of Thymol by Electrolysis in Acetonitrile and Methanol
Authors: Taniguchi Isao , Takada Kouzou , Yamaguchi Hiroko , Yasukouchi Kazuo 
Published: July 2006

Abstract
For anodic bromination of thymol, MeCN and MeOH were suitable solvents for mono- and dibromination respectively. In MeCN, no dibrominated product was observed even when four Faradays per mole of thymol were passed.
Preparation and Properties of a Mercury Selective Ion Exchanger Cerium(IV) Selenite
Authors: Rawat Jagdish Prasad , Khan Masood Akhtar , Thind Pritam Singh 
Published: July 2006

Abstract
A new inorganic ion exchanger, cerium(IV) selenite has been synthesized with a cation exchange capacity of 0.98 mequiv g−1. It is fairly stable in water and in dilute solutions of acids, bases and salts. The Kd values for number of metal ions were determined in different solvent systems. The exchanger possesses a high affinity for Hg(II) and hence its separation from certain metal ions have been made.
Preparation and Characterization of Dinitrosylmolybdenum Chelate Complexes
Authors: Nagaraja K S , Udupa M R 
Published: July 2006

Abstract
Nitrosyl complexes of molybdenum with the composition Mo(NO)2L2 (HL=8-quinolinol, 2-mercaptobenzothiazole, 2-pyridinethiol, or ethylmercaptoacetate) have been prepared. The infrared spectral absorptions at 1740 and 1625 cm−1 indicate that the nitrogen monoxide groups are coordinated as NO+ and are cis to each other. The 1H-NMR spectral studies are also presented. The analytical, magnetic and spectral data suggest that molybdenum is in formal zero oxidation state with octahedral coordination completed by univalent bidentate ligands.
A Model for Interactions of Amino Acid Side Chains with Watson-Crick Base Pair of Guanine and Cytosine. Crystal Structures of 9-(2-Carboxyethyl)guanine and Its Crystalline Complex with 1-Methylcytosine
Authors: Fujita Sigeo , Takenaka Akio , Sasada Yoshio 
Published: July 2006

Abstract
A new compound, 9-(2-carboxyethyl)guanine, was successfully synthesized and its crystalline complex with 1-methylcytosine was prepared, in order to investigate the protein-nucleic acid interactions involving guanine base. The crystal structures of 9-(2-carboxyethyl)guanine (cx9G) and of the complex of cx9G with 1-methylcytosine (cx9G:m1C) were determined by the X-ray analysis. Crystal data: cx9G, P21/c, a=12.221(3), b=11.022(2), c=6.961(2) Å, β=100.22(2)°; cx9G:m1C, P\bar1, a=8.932(1), b=12.370(1), c=7.139(1) Å, α=85.01(1), β=99.21(1), γ=86.64(1)°. In cx9G, the carboxyl group is doubly hydrogen-bonded with N(2) and N(3) of the guanine moiety of the adjacent molecule, N(2)–H···O distance being 2.939(5) Å and N(3)···H–O 2.660(5) Å for N···O. In cx9G: m1C, the guanine moiety and 1-methylcytosine form a Watson-Crick base pair. The carboxyl group takes an O=C–OH antiperiplanar conformation and is hydrogen-bonded with N(7) of guanine in the adjacent base pair. This hydrogen bond distance is very short, 2.634(2) Å, though the unfavorable conformation of the carboxyl group. This may suggest the marked preference of the carboxyl group for N(7) of guanine in the Watson-Crick base pair. On the basis of the geometrical data found in the present crystals, some possible models of interactions were constructed and examined, for example, aspartic or glutamic acid residue in the major groove of double stranded DNA.
A Kinetic Study on the Chemiluminescence of 9-Alkylacridines upon Air Oxidation in Alkaline Aprotic Solvents
Authors: Kamiya Isao , Sugimoto Takashi , Yamabe Kuniaki 
Published: July 2006

Abstract
9-Methyl- (1a), 9-benzyl- (1b), 9-(diphenylmethyl)- (1c), and 9-ethylacridine (1d) were employed to obtain luminescent features of the acridines. The decay of chemiluminescence (CL) exhibits a pseudo-first order behavior with apparent rate constants 0.10, 3.30, 4.10, and 0.07 min−1 at 312 K for 1a, 1b, 1c, and 1d, respectively. A relatively high CL quantum yield (6.3×10−3) is provided for 1a, in contrast to low yields for 1b, 1c, and 1d (1.5×10−6, 1.1×10−5, and 1.3×10−4, respectively). A reaction mechanism involving a cleavage of a dioxetane intermediate to give excited singlet acridone anion is plausible for the luminescent reaction. In view of the fact that several dioxetanes decompose to give excited singlet products in high yields, the CL appears to arise from a minor reaction.
The Effect of 4-Hydroxyl Substituent on the Singlet Chemiexcitation Yield in Base-catalyzed Air Oxidation of 3,5-Dichlorophenylpyruvic Acids
Authors: Kamiya Isao , Murata Shizuaki , Yamabe Kuniaki 
Published: July 2006

Abstract
In base-catalyzed air oxidation of substituted phenylpyruvic acids, an excited singlet product is generated from 3,5-dichloro-4-hydroxyphenylpyruvic acid (1) but excited triplet products from 3,5-dichlorophenyl-(2) and 3,5-dichloro-4-methoxyphenylpyruvic acid (3). According to the reaction scheme proposed, the singlet chemiexcitation yield from 1 and the triplet yields from 2 and 3 are 1·2×10−4, 8.3×10−4, and 6.7×10−4, respectively. A discussion is made on the difference in spin state selectivity between 1 and 2 or 3.
Flash Photolysis Study for Substituent and Solvent Effects on Spin-trapping Rates of Phenylthiyl Radicals with Nitrones
Authors: Ito Osamu , Matsuda Minoru 
Published: July 2006

Abstract
The spin-trapping rates for the reactions of para-substituted phenylthiyl radicals with nitrones have been determined by flash photolysis. For the phenylthiyl radical, the rate constant (in mol−1 dm3s−1) in benzene for a cyclic nitrone, 5,5-dimethyl-1-pyrroline N-oxide, is 5.2×108, which is greater than that for acyclic one, N-t-butyl-α-toluenimine N-oxide (1.1×107). The rates decrease with the solvent polarity and with the hydrogen-bonding ability; the maximum ratio of ca. 30 is observed for the rates between cyclohexane and methanol. Combined with the observed substituent effects, the mechanisms of the reactions and properties of the transition states are discussed.
Dispersibility of Magnetic and Nonmagnetic Iron(III) Oxides in Cyclohexane and Effect of Water on the Stability
Authors: Kandori Kazuhiko , Kazama Akio , Kon-no Kijiro , Kitahara Ayao 
Published: July 2006

Abstract
The dispersion stability of needlelike and octahedral iron(III) oxides of magnetic or nonmagnetic particles in cyclohexane solutions of sodium 1,2-bis(2-ethylhexyloxycarbonyl)ethanesulfonate (Aerosol OT or AOT) was studied on anhydrous and hydrous systems. The dispersion stability of the anhydrous system was examined for seven kinds of oxides. The sedimentation velocity of dispersions, the histograms of particle distribution, the adsorption of Aerosol OT on the particles and zeta potential were measured. Potential energies of the interaction between a pair of particles were calculated for the anhydrous system. It was suggested from the calculation of potential energies that the magnetic attractive force, which is a function of the strength of the saturation magnetization and the volume of particle, is a main factor affecting the flocculation of the magnetic particles in cyclohexane as well as in 2-butanone reported in the previous papers. The study of the dispersion stability of the hydrous system was done for three kinds of needlelike oxides. The relatively stable region appeared in the lower concentration range of water. The stability decreased at the fixed water concentration followed by marked flocculation (“floc formation” region). It was considered that the appearance of the “floc formation” is caused by the formation of thick hydration layer on the oxide surface and the decrease of zeta potential.
Simple Estimation of Ionization Energies. An Improvement of Koopmans’ Approximation by Scaling
Authors: Isihara Makoto 
Published: July 2006

Abstract
A simple method of estimating ionization energies is proposed, formulation being made for atomic systems. The method aims at improving Koopmans’ approximation by incorporating a scale factor into Koopmans’ variation problem for the hole state in the space built of the occupied Hartree-Fock manifold of the parent state. The shrinking of the electronic cloud through ionization is effectively taken into account with the scale factor; the scaling makes the hole state fulfil the virial theorem. Numerical examples are given for valence-shell and core ionizations of several atomic systems. The results are encouraging on the whole. The attendant concepts, the quasiparticle ejection energy and the global correction, seem to be helpful in understanding the electronic behavior through ionization.
The Theory of Liquid Ion-exchange Membrane Ion-selective Electrodes Based on the Concept of the Mixed Ion-transfer Potential
Authors: Kakiuchi Takashi , Senda Mitsugi 
Published: July 2006

Abstract
The theory of liquid ion-exchange membrane ion-selective electrodes has been developed on the basis of the concept of the zero-current potential, or the mixed potential in the presence of interfering ions, of ion transfer at the interface between a liquid membrane and a sample solution. Under the assumptions of the reversible ion transfer at the interface, the presence of supporting electrolytes in both phases, and the monovalency of all relevant ions, theoretical equations for the mixed potential are derived for two cases; the primary and interfering ions have 1) the same charge sign and 2) the opposite sign. The selectivity coefficients of the ion-selective electrodes can be expressed as a function of the difference between the standard ion-transfer potentials of the primary and interfering ions, the ratios of the mass-transfer coefficients of the ions, and the ratios of the concentrations of the ions. The theoretical prediction has been shown to be applicable to an interpretation of the response of liquid-membrane ion-selective electrodes.
Syntheses and Crystal Structures of Diaquatris(m-hydroxybenzoato)lanthanoid(III) m-Hydroxybenzoic Acid Dihydrate (M=La, Ce, Pr, and Nd), and Di-μ-(m-hydroxybenzoato)bis{triaquabis(m-hydroxybenzoato)lanthanoid(III)} Dihydrate (M=Sm, Gd, Dy, Er, and Yb)
Authors: Koizumi Yukio , Sawase Hiroshi , Suzuki Yasuo , Takeuchi Toshio , Shimoi Mamoru , Ouchi Akira 
Published: July 2006

Abstract
Two types of lanthanoid(III) m-hydroxybenzoates, indicated in the title, have been synthesized, and the crystal and molecular structures of four representative complexes, where M=La (1), Nd (2), Sm (3), and Er (4), were determined by the single-crystal X-ray diffraction method. They are all triclinic, space group P\bar1, and the cell constants are as follows: (1) a=12.351(11), b=15.533(10), c=9.250(4) Å, α=109.86(4), β=101.40(6), γ=62.95(6)°; (2) a=12.287(4), b=15.542(7), c=9.194(3) Å, α=109.64(3), β=101.46(3), γ=62.83(3)°; (3) a=10.580(1), b=12.006(5), c=10.105(2) Å, α=111.14(2), β=90.27(1), γ=97.16(2)°; (4) a=10.586(4), b=11.943(6), c=10.027(5) Å, α=111.11(3), β=90.53(4), γ=97.26(4)°. The final R values obtained were (1) 0.039, (2) 0.038, (3) 0.030, and (4) 0.039. The central metal atoms of both types of complexes are octa-coordinated, and each is in a square-antiprism geometry. In 1 and 2, one free acid molecule is present, and the molecule is hydrogen-bonded to the oxygen atoms of the coordinated water molecules through its carboxyl oxygen atoms. 1 and 2 have linear polymeric structure, and each pair of the metal atoms is bridged by a pair of the carboxylate ligands, while 3 and 4 have a dimeric structure, where metal atoms are bridged by two carboxylate ligands.
Reactions of Metal Complexes with Carbohydrates. Synthesis and Structure of (2-[(2-Aminoethyl)amino]-2-deoxy-l-sorbose)(ethylenediamine)nickel(II) Dichloride Hemi Methanol Solvate: [Ni(en)(l-sor-en)]Cl2·1/2CH3OH (en=ethylenediamine and sor=sorbose)
Authors: Tsubomura Taro , Yano Shigenobu , Toriumi Koshiro , Ito Tasuku , Yoshikawa Sadao 
Published: July 2006

Abstract
The synthesis and crystal structure of the complex [Ni(en)(l-sor-en)]Cl2·1/2CH3OH which was derived from the reaction of tris(ethylenediamine)nickel(II) dichloride dihydrate with l-sorbose are described. Crystal-lographic details for the complex are follows: space group C2 (monoclinic); a=17.862(2) Å, b=8.212(1) Å, c=12.644(2) Å, β=90.89(1)°; Z=4; Dcalcd=1.53 gcm−3. The structure was solved by heavy atom methods, and the structure parameters including almost all hydrogen atoms were refined by least-squares methods. The final R factor was 0.032 for 2680 independent reflections. The nickel atom is octahedrally coordinated with a bidentate ethylenediamine and a tetradentate glycosylamine ligand of l-sor-en. l-Sorbose moiety adopts the six-membered α-2C5 chair conformation. In addition to the synthesis and structure of this complex, we report the results of absorption and circular dichroism spectroscopy.
Inductively Coupled Plasma Atomic Emission Spectrometry Utilizing a Direct Graphite Cup Insertion Technique
Authors: Haraguchi Hiroki , Abdullah Mohammad , Hasegawa Tetsuya , Kurosawa Masao , Fuwa Keiichiro 
Published: July 2006

Abstract
A preliminary study on analytical performances of graphite sample cups is described for an instrumental assembly to carry out microliter volumes of liquid sample analysis. The graphite cup with a graphite rod and an insulating handle is inserted axially via the injector tube of a quartz torch into a low power operated inductively coupled argon plasma. Univariate search method has been employed for optimization of cup size, rod height and plasma operating parameters for manganese ionic line at 257.6 nm to obtain the most favorable net signal-to-background ratio. Detection limits, reproducibilities and dynamic ranges are also reported for manganese, zinc, lead, chromium, and nickel in solution.
Electrode Kinetics of Viologen Polymers Attached on Graphite Surfaces
Authors: Ohsaka Takeo , Yamamoto Hisao , Kaneko Masao , Yamada Akira , Nakamura Michiko , Nakamura Setsuko , Oyama Noboru 
Published: July 2006

Abstract
A “heterogeneous” electron-transfer process of three kinds of viologen polymers, i.e., N,N′-dimethyl-4,4′-bipyridinium (methylviologen, MV)–NafionR, poly(xylylviologen) (PXV)-poly(p-styrenesulfonate) (PSS) and poly(methylviologen) (PMV), in which MV and PXV were electrostatically trapped in Nafion and PSS, respectively, on a basal-plane pyrolytic graphite (BPG) electrode and PMV was directly attached to the BPG electrode surface, was examined by normal pulse voltammetry. The relevant kinetic parameters (i.e., the standard rate constant, koel and the cathodic transfer coefficient, α) of the electrode reaction and the apparent diffusion coefficients, Dapp, for the “homogeneous” charge transport within these polymer films were determined at the various surface concentrations (ΓMV2+ in units of mol cm−2) of viologen dication site. With the PMV and PXV–PSS systems, both koel and Dapp were independent of ΓMV2+, while with the MV–Nafion system both koel and Dapp decreased with an increase in ΓMV2+ under the constant concentration of Nafion. The values of α were independent of ΓMV2+ and constant (i.e., 0.56, 0.58, and 0.20 for the PMV, MV–Nafion and PXV–PSS systems, respectively).
Some Palladium(II) Complexes Containing Both the O-Unidentate β-Diketonato and 2-, 3-, or 4-Pyridyl Ligands. Dynamic Behaviors of trans-[Pd(β-dik-O)(C5H3(6-Cl)N-C2)(PEt3)2] in Solution
Authors: Tanaka Hiroshi , Isobe Kiyoshi , Kawaguchi Shinichi , Okeya Seichi 
Published: July 2006

Abstract
Palladium(II) complexes of the [Pd(β-dik-O)(pyridyl)(PEt3)2] type containing an O-unidentate acetylacetonate, trifluoroacetylacetonate, or hexafluoroacetylacetonate anion and a 2-, 3-, 4-pyridyl or 6-chloro-2-pyridyl group as ligands were prepared and characterized mainly by 1H and 13C NMR spectroscopy. The acetylacetonate and hexafluoroacetylacetonate ligands in the [Pd(β-dik-O)(C5H3(6-Cl)N-C2)(PEt3)2] complexes undergo the head-to-tail donor-atom exchange reaction, to which an intramolecular mechanism is proposed.
Preparation and Reaction of 1-(Methylthio- and phenylthio)vinyllithium Reagents
Authors: Takeda Takeshi , Furukawa Hiroyuki , Fujimori Mizue , Suzuki Kouichi , Fujiwara Tooru 
Published: July 2006

Abstract
An improved procedure for the preparation of 1-(methylthio- and phenylthio)vinyllithium reagents utilizing 2-methoxyalkyl sulfides was developed and their reactions with ketones, aldehydes, oxiranes, and alkyl halides were studied.