bluuebunny/crossref_metadata_2025 huggingface dataset:
Certain Interactions between Transition Metal Ions and the NCS Group in Chromium(III) Isothiocyanato Complexes. I. Reinecke’s Salt Type Complexes Involving Cobalt(II) and Copper(II) Ions
Authors: Oki Hisaya , Kyuno Eishin , Tsuchiya Ryokichi
Published: July 2006

Cobalt(II) tetraisothiocyanatochromate(III), Co[Cr(NCS)4(NH3)2]2, was prepared from cobalt(II) chloride and Reinecke’s salt in an aqueous solution. The absorption spectrum gave evidence that the so-called “cobalt-salt” dissociated into cobalt(II) cation and Reineck’s anion in aqueous solution. The reflection spectrum showed a remarkably strong absorption band at 14.08×1013 sec−1, which might be assigned to bonding between cobalt(II) and sulfur in an NCS− ligand. The three absorption peaks observed at 2158, 2095 and 2065 cm−1 in the IR spectrum due to C–N stretching vibrations also emphasized the strong interaction between cobalt and sulfur. The effective magnetic moment estimated was 4.58 B. M. at 18.3°C. The corresponding copper(II) salt, Cu(OH)[Cr(NCS)4(NH3)2], was obtained from an aqueous solution of copper(II) sulfate and Reinecke’s salt as a yellow powder. It was a sparingly soluble in water. In the reflection spectrum, the red-shifted band covered much of the first band region of Reinecke’s salt and in the IR spectrum, the C–N band had only a small splitting. The magnetic moment was found to be 3.84 B. M. at 16.0°C, which is close to the predicted value in the complex when copper is reduced, becoming univalent. X-Ray diffraction analysis also showed a relatively stronger contraction of the unit cell in the copper salt than in the cobalt salt. On the basis of the above points, it was proposed that in the copper salt there is considerable π-bonding between copper and the two adjacent isothiocyanate groups.
Studies on Some Telluro-Tungstomolybdates
Authors: Pathak Keshawa Chandra
Published: July 2006

Ammonium telluro-tungstomolybdate 6(NH4)2O·2TeO3·WO3·10MoO3·30H2O and the corresponding salts with silver, strontium, barium, cerium, lead, iron and guanidine have been isolated, their properties studied and the composition determined by the analytical methods. IR spectra of ammonium and guanidine salts have been recorded and the characteristic peaks assigned. Thermal decomposition studies (TGA and DTA) of ammonium salt were made. Differential thermal analysis of ammonium salt was done in nitrogen atmosphere too.
The Chromium(III) Complexes with Ammoniapropionicdiacetic Acid
Authors: Uehara Akira , Kyuno Eishin , Tsuchiya Ryokichi
Published: July 2006

Ammoniapropionicdiacetic acid (APDA), which belongs to a group of chelating agents similar to that of ammoniatriacetic acid, was prepared. The newly-prepared complexes containing this chelating agent were as follows: [Cr(OH)(apdaH)(H2O)2] (red purple) (I), NH4[Cr(OH)(apda)(H2O)]·2H2O (purple) (II), (NH4)3[Cr(apda)2]·2H2O (pink) (III), (Cr(apda)-(bipy)]·3H2O (brown) (IV), [Cr(apda)(o-phen)]·3H2O (brown) (V), and [Cr(apda)(py)2](pink) (VI), where apda, bipy, o-phen, and py are the abbreviations of the ammoniapropionate-diacetate ion, o-phenanthroline, 2,2′-bipyridyl, and pyridine respectively. On the basis of the chemical and thermal analyses, and on the basis of the measurements of the visible, UV, reflection and IR spectra and molar conductivities, it was concluded that the ammoniapropionatediacetate acts either as a terdentate or a quadridentate ligand in these complexes. Unlike the ATA complex, no complexes in which the nitrogen dose not coordinate with chromium could be prepared in the case of APDA. The values of the effective magnetic moments for these APDA complexes were nearly equal to the spin-only values of tervalent chromium. Further comparisons of the properties of the APDA complexes with those of the ATA complexes were also made.
Kinetics of Electron-Transfer Reactions Involving Ethylenediaminetetraacetatochromate(II) Ions as Reductants. II. Reactions with Some Acidopentaamminechromium(III) Complexes
Authors: Ogino Hiroshi , Tanaka Nobuyuki
Published: July 2006

The rate of the electron-transfer reactions between ethylenediaminetetraacetatochromate(II) and some acidopentaamminechromium(III), CrX(NH3)52+, has been measured at ionic strength 1.0 (NaClO4). The rate constants (l mol−1sec−1) for X=F−, Cl−, Br− and OH− are 2.07 at 25°C, >2×103 at 25°C, 2×103 at 15°C and 2.4×102 at 25°C, respectively. These reactions produce ethylenediaminetetraacetatochromate(III) ions which do not contain an anion X. The mechanisms of these reactions are discussed.
Further Studies on Acetoxylation of Isodihydro-O-acetylisophotosantonic Lactone
Authors: Sasaki Tadashi , Eguchi Shoji
Published: July 2006

Acetoxylation of O-acetylisophotosantonic lactone (I) and its isodihydro derivative (III) with lead tetraacetate was reinvestigated. The reaction of III in refluxing benzene afforded the known 2-acetoxy derivative (V) as the main product and α-diketone as the minor product which was isolated in its 2-keto-3-ol form (VII). The use of boron trifluoride- etherate as a catalyst in this acetoxylation, however, did not give good results. The ORD curves of dihydro-O-acetylisophotosantonic lactone (II), III, 2-bromo-isodihydro-O-acetylisophotosantonic lactone (IV), V and one of the hydrogenolysis product of I (X) were measured and some stereochemical problems of these compounds were discussed.
Ribonuclease T1 Peptides. III. Synthesis of a Protected Heptapeptide Corresponding to Sequence 24–30
Authors: Kato Tetsuo , Mitsuyasu Nobuo , Waki Michinori , Makisumi Satoru , Izumiya Nobuo
Published: July 2006

A protected heptapeptide corresponding to sequence 24–30 of ribonuclease T1, namely benzyloxycarbonyl-O-benzyl-l-tyrosyl-l-glutaminyl-l-leucyl-l-histidyl-γ-t-butyl-l-glutamyl-β-t-butyl-l-aspartyl-glycine ethyl ester (XI), was synthesized by coupling of benzyloxycarbonyl-O-benzyl-l-tyrosyl-l-glutaminyl-l-leucine azide with a tetrapeptide ester, l-histidyl-γ-t-butyl-l-glutamyl-β-t-butyl-l-aspartyl-glycine ethyl ester, which is derived from Nα,Nim-dibenzyloxycarbonyl tetrapeptide ester by the catalytic hydrogenolysis. These tri- and tetrapeptide components were prepared with stepwise syntheses free from racemization.
Syntheses of Citral and Citronellal by the Dehydrogenation of Geraniol Using Cu, Cu-Zn, Cu-Cr, and ZnO Catalysts
Authors: Kogami Kunio , Kumanotani Ju
Published: July 2006

The present paper describes the study of the syntheses of citral and citronellal by the catalytic dehydrogenation of geraniol with Cu, Cu-Zn, Cu-Cr, and ZnO catalysts under an atmospheric or a reduced pressure in vapor and liquid-phase systems. The following results were obtained: (1) the vapor-phase dehydrogenation with the Cu-Zn catalyst, conducted at a reduced pressure, was found to be most favorable, (2) when using this catalyst at 230°C, the addition of citronellal as a hydrogen acceptor prior to the dehydrogenation increased the yield of the citral from 50% to 85% (at 185°C, the highest yield of citronellal, 70%, was obtained). The composition of the product was analyzed by means of G. L. C. The reaction scheme under various conditions is also described briefly.
Solvent and Temperature Effects on the Proton hfs in the ESR Spectra of the Organic Radical
Authors: Aono Shigeyuki , Suhara Masahiko
Published: July 2006

A theoretical investigation is made into the solvent and temperature effects on the proton hfs in the ESR spectra of such organic radicals as:

(Remark: Graphics omitted.)

where X stands for the CH3 group, in several solvents. Both effects are explained on the assumption that a molecular complex is formed between radical and solvent, so that the charge-transfer occurs from radical to solvent: The solvent effect is caused by the fact that, in various solvent molecules, slight changes take place in their lowest vacant levels, which are occupied by the electron transferred from the radical; on the other hand, the temperature effect is explained by the thermal motion of the molecules, which changes the probabilities of the radical being in the solvated state and in the free state.
Kinetics of Oxidation of Pinacol by Peroxydisulphate Catalysed by Silver Ions
Authors: Menghani G D , Bakore G V
Published: July 2006

The kinetics of the reaction between peroxydisulphate and piancol catalysed by silver ions (Ag+) has been studied. The rate of peroxydisulphate disappearance was found to be dependent (i) on [S2O82−] (ii) on (Ag+). The rate is independent of the concentration of pinacol. Effects of [H+], temperature on the rate were studied. ΔE, Pz, ΔS, ΔF, etc. were evaluated. Mechanism of oxidation of pinacol based on the formation of reactive [Ag2+] is postulated.
Synthesis of Copper(II) Complexes with Maleic Acid
Authors: Gora Kazuo , Kyuno Eishin , Tsuchiya Ryokichi
Published: July 2006

Three copper(II) complexes with maleic acid, [Cu mal(H2O]) (I) (mal=C2H2(COO)2), [Cu(Hmal)2(H2O)4] (II) and [Cu2(Hmal)4]·H2mal·4EtOH (III) (EtOH=C2H5OH), were synthesized. Compound I was prepared from an aqueous solution of copper(II) sulfate pentahydrate and sodium hydrogenmaleate at room temperature as fine blue crystals. Compound II was prepared by adding little by little copper(II) hydroxide or copper(II) hydroxycarbonate to an aqueous solution of maleic acid at a temperature below 0°C in an ice-salt bath, obtaining light-blue powdered crystals. Compound III was prepared by heating a mixed alcoholic solution of maleic acid anhydride, copper(II) sulfate pentahydrate and sodium carbonate anhydride (3:1:1) in a flask with a reflux condenser for two hours. Fine bluish-green crystals were obtained. By using copper(II) hydroxide instead of copper(II) sulfate in the above preparation, a better yield can be obtained. The effective magnetic moments of I and II were 2.00 B. M. (20°C) and 1.97 B. M. (20°C), respectively, which are relatively close to the spin-only value of the divalent copper ion. On the other hand, the magnetic moment of III was subnormal, being 1.12 B. M. (18°C). The reflection spectrum of III gave a shoulder near 370 mμ, which is specific to green copper complexes. The product (IV) obtained by the thermal decomposition of I at 220°C and the product (V) obtained from II at 160°C, which are presumed to have the chemical formula [Cu-mal(H2O)0.1] and [Cu(Hmal)(mal)1⁄2], respectively, gave normal magnetic moments, 1.91 and 1.89 B. M. (20°C). However, product (VI), obtained by expelling the alcohol from III had a magnetic moment of 1.31 B. M. (17°C). Different from the corresponding copper(II) phthalate complexes, no green copper complexes having subnormal magnetic moments could be obtained through dehydration of the blue maleate complex I or the light-blue complex II having normal magnetic moments.
The Separation of the Cerium-group Rare Earth Elements by Ion Exchange using a Citrate-acetate Mixed Solution as Eluting Agent
Authors: Shibata Muraji , Tanabe Isao , Okuda Kinnosuke , Kadota Kazuo
Published: July 2006

The separation of rare earth elements by ion exchange was studied. The new eluting agent consists of an aqueous solution of diammonium hydrogencitrate and an aqueous ammoniaacetic acid mixture; the two solutions were mixed in definite ratios. Using a column of Dowex 50 W resin, the separation of Sm, Nd, Pr, Ge and La was successfully achieved. As practical samples, mixed chlorides obtained from monazite concentrates were used. Both the purities and the yields of the recovered rare earths were greater than 99%. This eluting agent was applied to the separation of yttrium-group rare earths such as Dy, Er, Yb and Y, but the attempt was not successful.
Ultramarines Synthesized under Controlled Sulfur Vapor Pressures
Authors: Yamaguchi Goro , Kubo Yasushi
Published: July 2006

Ultramarine was synthesized in the systems NaAlSiO4-Na2S and NaAlSiO4·aNa2O-Carbon under a sulfur vapor pressure controlled between 0 and 1 atm. The average valence of sulfur contained in ultramarine changed from 2.0 to 1.0 with increase in sulfur vapor pressure. This was due to the formation of a sulfide containing monosufidic sulfur ion at 0 atm and of a polysulfide containing disulfidic ion at elevated sulfur vapor pressures. Sigmoidal characteristics were observed in the relationships between the sulfur content of ultramarine and the sulfur vapor pressure.
Free Radical Reactions in Organic Electrode Processes. VII. Anodic Reaction of Benzoic Acid with Aromatic Hydrocarbons
Authors: Koyama Kikuhiko , Ebara Tatsuyoshi , Tsutsumi Shigeru
Published: July 2006

The anodic reaction of benzoic acid in acetonitrile containing tiethylamine was carried out in the presence of toluene, ethylbenzene, cumene, and tetralin. The amounts of carbon dioxide evolved during the electrolyses were smaller than those expected to be produced through the spontaneous decomposition of the benzoyloxy radical. An examination of nongaseous products indicated that the anodic reaction proceeds by means of the formation of the benzoyloxylates and phenylates of the aromatic hydrocarbons present. The occurrence of the nuclear benzoyloxylation, to a relatively great extent, suggested that the aromatic hydrocarbons were oxidized at the anode.
Long-Range Spin Coupling between the Methoxyl and Ring Protons in 2-Methoxytropone Derivatives and Its Applications
Authors: Seto Shuichi , Ogura Kyozo , Toda Hiroko , Ikegami Yusaku , Ikenoue Tsuneo
Published: July 2006

Bromination of 5-amino-2-methoxytropone and 2-amino-7-methoxytropone afforded 5-amino-4-bromo-2-methoxytropone and 2-amino-3,5-dibromo-7-methoxytropone, respectively, as expected from the consideration of the effect of amino group in 2-methoxytropone system. Long-range spin coupling between the methoxyl group and a neighboring ring proton was observed in 2-methoxytropone derivatives. This information was applied to elucidation of the structure of the bromination products. The comparison of their NMR spectra gave the reasonable assignment for the ring protons of 5-amino-2-methoxytropone.
Lactone Carboxylic Acids. VI. A Synthesis of α,β-Epoxybutyrolactone via α-Diazolactones
Authors: Torii Sigeru , Endo Siro , Oka Hirotosi , Kariya Yoshihiro , Takeda Akira
Published: July 2006

Reaction of α-carboxy-β-carbethoxy-γ,γ-dimethylbutyrolactone (3) with equimolar amount of nitrous acid gave ethyl α-hydroxyaminoaconate (7). However, the nitrosation of 3 using excess nitrous acid afforded a variety of compounds such as α-diazo (4 and 5), α-nitro (8), and α-azoxybutyrolactone (9) derivatives. Each of the products (4, 5, 8, and 9) could be synthesized from 7, independently. By the action of phosphoric acid, α-diazolactones (4 and 5) were converted into ethyl α,β-epoxyparaconate (6). The nature of the product 7 was demonstrated through its conversion into ethyl α-hydroxyaconate and through its thermal decomposition to ethyl α-aminoaconate and a-isopropylidenecyanoacetic acid derivatives. A possible mechanism for the formation of 6 through 4 and 5 is described.
Synthesis of 3-Vinylpyrene by Wittig’s Reaction, and Syntheses and Electrical Properties of Polyvinylpyrene and Its Charge Transfer Complexes
Authors: Tanikawa Kiyoshi , Ishizuka Takashi , Suzuki Kojiro , Kusabayashi Shigekazu , Mikawa Hiroshi
Published: July 2006

Using Wittig’s reaction, we synthesized 3-vinylpyrene from pyrene-3-aldehyde in 76% yield. 3-Vinylpyrene monomer was polymerized by benzoylperoxide or di-t-butylperoxide catalysts. Each polymer had a melting point, being observed by the method of polarizing hot stage microscopic examination. X-ray examination showed that the polymer was crystalline, although rather poor. The charge transfer complexes, containing polyvinylpyrene as an electron donor, and iodine, tetracyanoethylene or tetracyanoquinodimethane as an electron acceptor, were prepared, each having the composition of pyrene nucleus : acceptor=16 : 3, 15 : 2, 15 : 2, respectively. Electrical conductivities of the complexes at 25°C, ρ25 and band gap energies, ε, were 1.3×108 Ωcm, 0.80 eV; 4.5×1012 Ωcm, 1.32 eV; 1.1×1014 Ωcm, 1.34 eV, respectively. Each complex showed ohmic current-voltage characteristics in an appropriate temperature range.
The Photochemical Reactions of Fe(III) Complexes with 1,2-Glycols. Dehydration and Dehydrogenation
Authors: Inoue Hiroo , Komakine Nobuyuki , Imoto Eiji
Published: July 2006

Ferric chloride reacts with 1,2-glycols, when irradiated with light, to afford dehydration and dehydrogenation products. The reaction course is influenced by the structure of the 1,2-glycols, the kind of ligand around the Fe(III) ion, and the solvent in the reaction system. When the number of hydrogen atoms on carbon having a hydroxyl group of 1,2-glycol increases, the yield of the dehydration product increases in comparison with that of the dehydrogenation product; the photochemical reaction of ferric chloride with ethylene glycol or pinacol gives, selectively, acetaldehyde or acetone respectively. The photochemical reaction of ferric acetate with the ethylene glycol shows a highly selective dehydrogenation, giving only formaldehyde, though it is in a good yield. Furthermore, the addition of aniline or acetic acid to the ferric chloride-ethylene glycol system results in an increase in the production of glyoxal or acetaldehyde respectively. In the photochemical reaction of ferric chloride with ethylene glycol or cis- and trans-1,2-cyclohexanediol, acetonitrile as a solvent causes the formation of the dehydrogenation products, that is, acetoxyacetaldehyde and glyoxal or 1,2-cyclohexanedione respectively.
Synthetic Studies of Sesamol Derivatives. X. Synthesis of Dehydroneotenone
Authors: Fukui Kenji , Nakayama Mitsuru
Published: July 2006

The synthesis of dehydroneotenone has been carried out using 6-hydroxy-5-(2-methoxy-4,5-methylenedioxyphenylacetyl)-2,3-dihydrobenzo[b]furan as an intermediate and by subjecting it to cyclization with ethyl orthoformate, followed by dehydrogenation.
A Convenient Method for the Preparation of Acid Anhydrides from Metallic Carboxylates
Authors: Hata Tsujiaki , Tajima Kiyohiko , Mukaiyama Teruaki
Published: July 2006

A convenient method for the preparation of carboxylic anhydrides by use of one mole of N,N′-dicyclohexylthiourea and two moles of silver or mercurous carboxylate has been established. According to this method, several carboxylic anhydrides were obtained in high yields under mild conditions even by microscale experiments.
Syntheses of 4-Alkylidene- and 4-Aralkylidene-2-chloromethyl-5-oxazolones and N-(Chloroacetyl)dehydroamino Acids
Authors: Kurita Hideaki , Chigira Yasuhiro , Masaki Mitsuo , Ohta Masaki
Published: July 2006

Treatment of N-dichloroacetyl amino acids with acetic anhydride at a temperature between 85°C and 130°C yielded 4-alkylidene- and 4-aralkylidene-2-chloromethyl-5-oxazolones, which were readily hydrolyzed to give 2-(2-chloroacetamido)-2-alkenoic acids, i.e., N-(chloroacetyl)-dehydroamino acids.
Stereospecific Synthesis of 1,4-Dienes. IV. The Catalytic Behavior of the Ethylenebis(diphenylphosphine) Complex of Iron(0)
Authors: Hata Go , Miyake Akihisa
Published: July 2006

A zerovalent iron complex, Fe(Ph2P·CH2CH2·PPh2)2· C2H2, catalyzes addition of ethylene to butadiene to afford 1 : 1 adducts consisting of 1,cis-4-hexadiene, 1,3-hexadiene, 2,4-hexadiene and 1,5-hexadiene, and 2 : 1 adducts. The combination of the iron complex and a Lewis acid (triethylaluminum, diethylaluminum chloride, ethylaluminum dichloride and boron trifluoride etherate) gives 1,cis-4-hexadiene much more selectively. The most efficient Lewis acid component for the synthesis of 1,cis-4-hexadiene is diethylaluminum chloride.
Analogs of Oxytocin Containing Leucinamide and Glycylglycinamide in Place of Glycinamide
Authors: Aoyagi Haruhiko , Kondo Michio , Izumiya Nobuo
Published: July 2006

Two analogs of oxytocin, [9-leucine]-oxytocin and oxytocinoyl-glycinamide, in which the glycinamide residue at position 9 in oxytocin has been replaced by a leucinamide and glycyl-glycinamide, respectively, have been synthesized and tested for some of the pharmacological properties characteristic of oxytocin. The protected nona- and decapeptide intermediates were prepared by use of the azide method in a fashion of the fragment condensation. After removal of the protecting groups from the intermediates by means of either sodium in liquid ammonia or anhydrous hydrogen fluoride, the dithiols thus obtained were oxidized to the required analogs. It was found that [9-leucine]-oxytocin possessed approximately 8% oxytocic potency, and oxytocinoyl-glycinamide 0.5% potency compared with oxytocin preparation.
Effect of Surface Active-Agents and Some Molecules on the Electrical Properties of Lipid Membranes
Authors: Hashimoto Masao
Published: July 2006

The electric and mechanical properties of lipid membranes between two electrolyte solutions were observed. The electric resistance was 107–108 Ω·cm2; the capacity, 0.2–1 μF/cm2, and the surface tension, 2.2–4.9 dyn/cm. The electric conductivity increased with an increase in the surface area of the lipid membranes. Furthermore, the electric resistance and the capacity decreased when an ionic surface-active agent was adsorbed to the lipid membranes. The effect may be caused by the structural change of the lipid membranes due to both the electric and the hydro-phobic interactions between the ionic surface-active agent and the lipid membranes.
The Structure of an Electrical Double Layer around a Surfactant Micelle
Authors: Tokiwa Fumikatsu , Ohki Kenji
Published: July 2006

Electrophoretic measurements have been made of the micelles of dimethyldodecylamine oxide (DDAO) and N-dodecyl-β-aminopropionic acid (DAPA), while changing the pH values of the solutions in the presence of 0.10 m sodium chloride. A picture of the structure of the electrical double layer around the micelle at different pH’s was then constructed, according to Stern’s theory, by a combination of the zeta potential, ζ, calculated from the electrophoretic mobility and the surface potential, ψ0, obtained previously from the potentiometric titration. With the micelle of DDAO, the thickness of the immobile part of the double layer depends slightly on the pH of the solution and is estimated to be about 5 Å. With the micelle of DAPA, the estimated thickness of the immobile part seems rather high, especially on the alkaline side of the solution. The ζ⁄ψ0 ratio for the micelles of DDAO and DAPA depends on the pH of the solution; in the case of DDAO the value of ζ⁄ψ0 increases with a decrease in the surface potential.
ESR Studies of Copper(II) Complexes of Ethylenediamine and Its Analogues
Authors: Yokoi Hiroshi , Isobe Taro
Published: July 2006

The ESR spectra of the copper(II) complexes of ethylenediamine, 1,2-diaminopropane, meso-2,3-diaminobutane, 1,3-diaminopropane, and ammonia were measured in methanolic and aqueous solutions at room temperature and in frozen solutions at the temperature of liquid nitrogen. The covalency of the bonding of the copper atom to the ligand atoms in these complexes was evaluated from the g values, the copper hyperfine constants, and the nitrogen super-hyperfine constants. Even in the case of amino groups which were coordinating groups, the π bonding seemed to be as important in determining the properties of the complexes as the σ bonding.
Reactions of cis- and trans-2-Butenes Photosensitized by Hg(3P1) and Cd(3P1)
Authors: Tsunashima Shigeru , Sato Shin
Published: July 2006

A comparative study has been made of the reactions of cis- and trans-2-butenes photosensitized by mercury(3P1) at room temperature and by cadmium(3P1) at temperatures ranging from 275 to 350°C. In both cases, the main reaction was cis-trans isomerization. The initial quantum yield of isomerization was the same for the two butenes. The rate of decomposition was about 10−2 and 10−3 times less than that of isomerization in the Hg- and Cd-photosensitizations, respectively. The ratio of trans- to cis-2-butene after prolonged irradiation was unity and did not vary with pressure in the Cd-photosensitization, while in the Hg-photosensitization it increased with decreasing initial pressure. This is probably due to the difference in the rates of decomposition of trans- and cis-2-butenes. It was found that the pressure dependence of Hg-photosensitized cis-trans isomerization could not be explained in terms of the simple mechanism proposed before. A possible mechanism is discussed.
The Structure of Meisenheimer Complex as Determined by X-ray Crystal Analysis
Authors: Ueda Hideo , Sakabe Noriyoshi , Tanaka Jiro , Furusaki Akio
Published: July 2006

The structure of the Meisenheimer complex has been determined by the X-ray method. The complex is characterized by a symmetrical structure, in which the two methoxyl groups are nearly equivalent to each other. The results showed a peculiar shape of the reaction intermediate, the substituted carbon atom is transformed into a tetrahedral shape, while the planarity of the whole molecule is kept with an increased conjugation between the nitro group and the ring system.
Addition of Some Simple Molecules to Transition Metal-Phosphine Complex and the Crystal and Molecular Structure of Pd{(C6H5)3P}2(CS2)
Authors: Kashiwagi Toshihide , Yasuoka Noritake , Ueki Tatzuo , Kasai Nobutami , Kakudo Masao , Takahashi Shigetoshi , Hagihara Nobue
Published: July 2006

From the reaction of M{(C6H5)3P}4 (M=Pd or Pt) with CS2, M{(C6H5)3P}2(CS2) has been isolated. It has been found that M{(C6H5)3P}2 also reacts with sulfur dioxide to form a novel complex, [M{(C6H5)3P}4(SO2)n]. The structure of one of these compounds, Pd{(C6H5)3·P}2(CS2), was determined by means of X-rays. Pd{(C6H5)3P}2(CS2) crystallizes in the mono-clinic system, space group P21⁄c, with four molecules in a unit cell of dimensions: a=11.55, b=19.52, c=18.38 Å and β=128°53′. The most remarkable feature of the whole structure is the coordination of CS2 to the Pd: only one of the S atoms, S(2), coordinates to the Pd, while the CS2 ligand is bent at an angle of 140°. The Pd, two P’s, S(2) and C(1) in CS2 lie approximately on the same plane. The Pd–C(1) distance of 2.00 Å is slightly shorter than the sum of the covalent radii, 2.06 Å. But the S(2)–Pd–C(1) angle of 44° is very small.
Ionic Species in the Radiolysis of Cyclohexane
Authors: Sato Shin
Published: July 2006

A diffusion model proposed in the previous paper (Bull. Chem. Soc. Japan, 40, 1818 (1967)) has been applied to explain the ionic reactions occurring in the γ-radiolysis of cyclohexane. The effects of an electron scavenger (N2O) and a positive ion detector (CH3OD) were consistently interpreted. The ratio of the diffusion coefficient of electrons to that of parent positive ions has been estimated from the calculation to be in the range of 4 to 5. The calculating method has been compared with that recently published by Freeman (J. Chem. Phys., 46, 2822 (1967)).
Effect of the Dielectric Constant on the Reaction between the Iodide Ion and Hexacyanoferrate(III) in Acid Media
Authors: Krishna B , Singh H S
Published: July 2006

In the reaction between the iodide ion and hexacyanoferrate(III), the order is unity with respect to the iodide ion and two with respect to the ferricyanide ion. It has been observed that the rate of the reaction increases with the increase in the dielectric constant of the medium. It has also been observed that the reaction occurred between trivalent and univalent negative ions.
Synthetic Inorganic Ion-exchange Materials. X. Preparation and Properties of So-called Antimonic(V) Acid
Authors: Abe Mitsuo , Ito Takuji
Published: July 2006

The preparation of so-called antimonic acid under various experimental conditions has been investigated in order to establish its usefulness as a chemically-stable cation-exchange material. In this experiment, the antimonic acid was mainly obtained by the hydrolysis of antimony pentachloride, and was rarely obtained from metallic antimony or potassium pyroantimonate. The hydrolyzed precipitate was amorphous at first, but it was gradually transformed into crystalline powder by keeping it in the mother liquor for a long time. The crystallization of the amorphous precipitate was facilitated by raising the temperature within a range of 0–80°C, and by increasing the concentration of strong mineral acid on aging, regardless of the kinds of starting antimony substances. The water-content of the air-dried samples is decreased by increasing the period of aging; the composition of the sample approximates Sb2O5·4H2O. The crystal of the antimonic acid is cubic and belong to the space group Oh7(Fd3m), with a lattice constant of 10.382 Å. The measurement of solubilities for the air-dried antimonic acid showed that both the amorphous and the glassy acids are soluble forms and that the crystalline is an insoluble form. The uptakes of potassium ions on these antimonic acids were little changed on the kinds of form; the uptake of lithium ions on the crystalline acid was very small as compared those on the amorphous and the glassy acids. This behavior may be attributed to the existence of different types of so-called antimonic acid, with different selectivities of their lithium ion adsorption, rather than to any difference in the size of the particle.
D. C. and A. C. Polarographic Behavior of Thallium(I) Ions in Diethylenetriaminepentaacetate Solutions
Authors: Kodama Mutsuo , Noda Tomohiko , Murata Mitsuko
Published: July 2006

The reduction reaction of Tl(I) ions in DTPA solutions was studied d.c- and a.c.-polarographically, and the composition and the stability constants of normal and hydrogen chelates of Tl(I) ions with DTPA, TlZ4− and TlHZ3− were determined. The reduction of Tl(I)-DTPA chelates at the DME proceeds reversibly in the polarographic sense according to this scheme:

(Remark: Graphics omitted.)

The stability constants of TlZ4−-and TlHZ3− were found to be 105.45 and 104.24(μ=0.40). The determination of the a.c. summit-potentials, Ep, and the introduction of Ep into the Kolthoff and Lingane equation of polarographic waves of metal complexes were also discussed.
The Synthesis of Methacrylic Esters by the Carboxylation Reaction of Methylacetylene. II. Catalytic Synthesis of Methyl Methacrylate using Nickel Carbonyl as the Catalyst
Authors: Kunichika Sango , Sakakibara Yasumasa , Nakamura Tadao
Published: July 2006

The catalytic synthesis of methyl methacrylate by the carboxylation reaction of methylacetylene using nickel carbonyl as a catalyst was studied under various conditions. The experimental results concerning the effects of the reaction conditions on the reaction rate, the stability (regeneration) of nickel carbonyl, and the product yields suggested the most desirable conditions for the synthesis. It was ascertained that, in the catalytic process, the pressure of carbon monoxide played a very important roles; a high pressure gave a good regeneration of nickel carbonyl, i. e., a high value of 95% in the so-called catalytic level, but the initial reaction rate decreased remarkably with an increase in the pressure, probably in reverse proportion to its second power, or more. A semicontinuous process was much better for the synthesis than a batch process. A good yield of 85% (based on the methylacetylene used) of the total of methyl methacrylate and methacrylic acid and a high catalytic level of 95% were obtained when the reaction was carried out semicontinuously in the presence of methacrylic acid and water at a total pressure of 13 atm (initial charge of carbon monoxide at room temp.: 4 atm) at 130°C. A mechanism for the catalytic reaction was proposed to account for the experimental results.
An NMR Study of Proton Exchange in Alcohols. II. Proton Transfer in the Water-Isopropanol System
Authors: Fukumi Toshio , Fujiwara Yuzuru , Arata Yoji , Fujiwara Shizuo
Published: July 2006

Proton exchange has been investigated in the system of water and isopropanol by means of high-resolution nuclear magnetic resonance. The rates of proton transfer have been obtained at different hydrogen ion concentrations and at different ratios of water and isopropanol. It has been shown that the exchange reaction is of higher order with respect to water and isopropanol concentrations. Possible mechanisms of proton transfer have been discussed, and values for their respective rate constants given.
The Reaction of Tropolones with Phosphorus Oxychloride. The Rearrangement Reaction of 5-Arylazo-2-chlorotropones to 2-Aryl-4, 5-dichloroindazoles
Authors: Kikuchi Katsuo , Yagi Masaki , Takada Kunio
Published: July 2006

The reaction of tropolone and phosphorus oxychloride gave 2-chlorotropone. Similarly, 5-cyano-, 5-nitro, and 5-chlorotropolones afforded the corresponding 2-chlorotropone derivatives in moderate yields. 3-Cyanotropolone gave 2-chloro-7-cyanotropone, while 3-phenyltropolone afforded only 2-chloro-3-phenylbenzaldehyde. When 3-bromotropolone and 5-bromotropolone were treated similarly, 2, 7-dichloro- and 2, 5-dichlorotropones were obtained respectively, with a facile halogen exchange. The further treatment of 2, 5-dichlorotropone with phosphorus oxychloride afforded 2, 5-dichloro- and 3,4-dichlorobenzaldehydes. The reaction of 5-p-tolylazo-, 5-phenylazo-, and 5-p-nitrophenylazotropolones with phosphorus oxychloride gave the corresponding 5-arylazo-2-chlorotropones, which, on further treatment with an excess of the reagent, gave 2-aryl-4, 5-dichloroindazoles.
Use of Anhydrous Hydrogen Fluoride in Peptide Synthesis. II. Procedures for the Syntheses of Simple Peptides
Authors: Sakakibara Shumpei , Kishida Yasuo , Nishizawa Rinzo , Shimonishi Yasutsugu
Published: July 2006

Detailed conditions for handling simple peptide-derivatives with anhydrous hydrogen fluoride (HF) were presented. Since HF has a strong affinity for peptides, the removal of excess HF from the reaction products is rather difficult, but is essential to obtain the product as good crystals. Syntheses of the following peptides were carried out successfully as examples of the HF procedure: tosyl-l-phenylalanyl-l-phenylalanine, l-leucylglycine, l-arginylglycine, carbobenzoxy-l-prolyl-l-leucylglycine ethyl ester, l-aspartyl-l-phenylalanine amide, and BOC-β-alanyl-l-tryptophyl-l-methionyl-l-aspartyl-l-phenylalanine amide.
Correlation between the Chemical Reactivity and the Unpaired Electron Distribution of Anion Radicals
Authors: Maruyama Kazuhiro , Otsuki Tetsuo
Published: July 2006

Anion radicals of mono-, di-nitrobenzophenones, dinitrobenzil, and nitrophenanthraquinone generated by reduction with alkali metal were studied by means of electron-spin resonance. The hyperfine coupling constant and the effect of the metal species on it were investigated. The correlation between the localization of the unpaired electron and the chemically reducible position was also discussed.
Thermodynamic Properties and Phase Transitions of Sodium Cyanide Crystal
Authors: Matsuo Takasuke , Suga Hiroshi , Seki Syûzô
Published: July 2006

The heat capacities of the sodium cyanide crystal were measured from 14 to 310°K by an adiabatic calorimeter. The two anomalous regions reported by Ziegler et al. are confirmed. The entropy changes associated with these anomalies is explained by proposing structural changes at the transition points. Analysis of the lattice heat capacity gives the average librational frequency of the cyanide ion at the lowest temperatures as 210 cm−1 in the Einstein approximation. For the higher temperature range, the cyanide ions may be described as undergoing a hindered rotation, with a barrier height of approximately 2 kcal/mol. The upper-phase transition is discussed in terms of a model based on the coexistence of the two crystalline phases. The lower transition and the analogous one reported previously for potassium cyanide are interpreted together as order-disorder phenomena with respect to the behavior of the cyanide ions. The thermodynamic functions of the crystal are also calculated by the graphical integration of the heat capacity data.
Conductance Behavior of Some Hexa-amminecobalt(III) Complexes and Their Ion Association in Aqueous Solutions
Authors: Katayama Shunzo , Tamamushi Reita
Published: July 2006

The conductance behavior of some hexa-amminecobalt(III) complexes in dilute aqueous solutions at 25°C was studied in association with the ion-pair formation of hexa-amminecobalt(III) ions. The equivalent conductivities were analyzed according to the Onsager theory, and the thermodynamic formation constants, K, of the ion-pairs, [Co(NH3)6]3+·Aza−, were determined. The logK values obtained are 1.40 (perchlorate), 1.63 (nitrate), 1.65 (bromide), 1.38 (iodide), and 3.25 (oxalate). These values were compared with the formation constants calculated from the spectroscopic data, and discussed in terms of Bjerrum’s theory on ion association.
Structural Study of the Molecular Complex of Antimony Trichloride with Benzene by Means of the Pure Quadrupole Resonance
Authors: Okuda Tsutomu , Nakao Akira , Shiroyama Masaharu , Negita Hisao
Published: July 2006

The Zeeman effect of 35Cl pure quadrupole resonance was studied on a single crystal of the 2SbCl3·C6H6 molecular complex at room temperature; it was found that the Cl–Sb–Cl bond angles of two nonequivalent SbCl3 molecules are 96.2°, 94.7°, 92.2°; 94.5°, 92.8°, and 95.2°, with an uncertainty of 1°. The asymmetry parameters for the six chlorine atoms were found to be 0.085±0.001, 0.055±0.004, 0.117±0.005, 0.119±0.005, 0.112±0.005, and 0.160±0.007, listed in the order of decreasing resonance frequencies. The bond character of the Sb–Cl bond was also calculated from the quadrupole coupling constant. It was found that the Sb–Cl bond corresponding to the lowest resonance lines in each nonequivalent SbCl3 molecule has a larger ionicity than the remainder. Moreover, the former has less of a temperature dependence than the latter. Finally, this complex may be assigned to the Ci or C1 symmetry class from the patterns of zero-splitting and from the intensity ratios of the multiplet of the spectrum.
A New Anion Exchanger Containing Cobalticinium Cation
Authors: Ito Takuji , Kenjo Tadao
Published: July 2006

A New type of anion-exchanger, polymeric olygomethylene cobalticinium cation, was synthesized and its ion-exchange properties and stability toward heat and reagents were investigated in comparison with those of the ion-exchange resins. The preparative method of the exchanger was the same as that for polymeric olygomethylene ferrocene; hexamminecobalt(II) chloride was added to the product of α, ω-dicyclopentadienyl alkane with sodium. Although the pure products could not be obtained, the substance extracted with water showed several peaks common to a cobalticinium cation in IR spectra. The content of cobalt in tetraphenyl borate was 0.175 mmol/g, which corresponded to 91% trimethylene cobalticinium tetraphenyl borate. The saturated ion-exchange capacity of the eschanger was 1.75 meq/g, which was half the theoretical value. This discrepancy could be attributed to the shortage of cobalt according to the results of chemical analysis and magnetic susceptibility measurements. Although ionexchange resins lose their exchange capacity by heating at 150°C in air, this exchanger was thermostable decreasing to only 70% in ion-exchange capacity. The ion-exchange capacity of the exchanger in hydrothermal water at 220°C decreased to 55–35%, while that of resins drops to as low as 20%. The selectivity coefficient for various anions became smaller in the order; ClO4−>I−>ClO3−>BrO3−>Br−>Cl−>IO3−>F−. This tendency was the same as that for ion-exchange resins.
Solvent Extraction of Cadmium(II) from Aqueous Chloride and Bromide Solutions by Tri-n-octylamine
Authors: Watanabe Hiroto , Akatsuka Kunihiko
Published: July 2006

The distribution of cadmium(II) between dilute hydrochloric or hydrobromic acid solution and tri-n-octylamine dissolved in a number of diluents has been measured for several cadmium (II) loadings and amine concentrations. Diluents investigated are n-hexane, cyclohexane, benzene, xylene, toluene, carbon tetrachloride, chloroform, chlorobenzene and o-dichlorobenzene. The results show that all the species extracted into various diluents are present in the form of bis(tri-n-octylammonium)tetrahalocadmium(II). The specific ability of each diluent in extracting cadmium(II) from acidic halide solutions is approximately correlated with the dielectric constant of the pure diluent, suggesting that the dissociation of ion paired alkylammonium salt in the organic phase is responsible for the extraction.
Chemical Synthesis of O-Ethyl-l-homoserine, a New Amino Acid Produced by Corynebacterium Ethanolaminophilum
Authors: Murooka Yoshikatsu , Harada Tokuya , Izumi Yoshiharu
Published: July 2006

The synthesis of O-ethyl-Dl-homoserine (V) was achieved by the condensation of β-ethoxyethylbromide (II) with diethyl acetoaminomalonate (III) and by the successive hydrolysis of diethyl ethoxyethylacetoaminomalonate (IV) with hydrochloric acid. The optical resolution of O-ethylhomoserine was performed enzymatically using papain. The O-ethyl-l-homoserine (VIII) obtained by the resolution was shown to be identical with the amino acid formed ethanol by Corynebacterium ethanolaminophilum, sp.nov.
Reactivity of Solid Acids with Methylene Chloride
Authors: Mochida Isao , Take Jun-ichiro , Saito Yasukazu , Yoneda Yukio
Published: July 2006

In order to discriminate the natures of solid acids, the reactivity of methylene chloride with solid acids like alumina, silica-alumina and alumina-boria to give carbon monoxide and methyl chloride was studied with a pulse technique. The reactivities varied about ten thousandfold among these solid acids. The methyl chloride formation was predominant on alumina particularly at low reaction temperatures, with a distinctly small activation energy in comparison with that on silica-alumina or alumina-boria. The nature of the active sites for this reaction was discussed in connection with the effect of the calcination temperature as well as of the sodium ion-poisoning on activity. Furthermore, it was found that the feature of this reaction was in marked contrast with the typical solid acid catalysis such as the dealkylation reaction of alkylbenzenes. The reaction of methylene chloride with a set of the surface hydroxyl group and the oxidizing site is assumed to give methyl chloride through a radical mechanism.
The Effect of Hydrogen Bonding on the Rates of Inversion of 1-Hydroxy-5, 7-dihydrodibenz[c,e]oxepin
Authors: Oki Michinori , Iwamura Hiizu , Nishida Toshiaki
Published: July 2006

The rates of inversion of 1-hydroxy-5, 7-dihydrodibenz[c,e]oxepin (I) and its methyl ether (II) have been measured by NMR line-shape method in several solvents. The activation parameters for inversion of II are insensitive to the change in solvents, while the activation energy of I in strongly proton-accepting DMSO is clearly smaller by one kcal/mole than that of I in CDCl3and those of II. The solvent effect may be due partly to the enhanced mesomerism of the biphenyl system as the result of hydrogen bonding and partly to the inhibition of the intramolecular O-H···π interaction which will otherwise stabilize the non-planar ground state in the inert solvents.
Ribonuclease T1 Peptides. II. Synthesis of a Protected Pentapeptide Corresponding to Sequence 12–16
Authors: Waki Michinori , Mitsuyasu Nobuo , Kato Tetsuo , Makisumi Satoru , Izumiya Nobuo
Published: July 2006

A protected pentapeptide corresponding to sequence 12–16 of ribonuclease T1 namely benzyloxycarbonyl-l-seryl-l-seryl-l-seryl-β-t-butyl-l-aspartyl-l-valine ethyl ester (XI), was synthesized by coupling of benzyloxycarbonyl-seryl-serine azide with a tripeptide ester, seryl-β-t-butylaspartyl-valine ethyl ester, which is derived from benzyloxycarbonyl-seryl-β-t-butyl-aspartyl-valine ethyl ester by the hydrogenolysis. The hydrogenolysis and the subsequent treatment with trifluoroacetic acid of the protected pentapeptide ester (XI) yielded a neutral pentapeptide ester, seryl-seryl-seryl-aspartyl-valine ethyl ester, as a crystalline product.
S-Alkylthioamidium Salt. II. The Reactions of S-Alkylthioamidium Iodides with Mercuric Compounds
Authors: Yamaguchi Tatsuaki , Inomata Katsuhiko , Mukaiyama Teruaki
Published: July 2006

The reactions of S-alkylthioamidium iodides with some mercuric compounds have been studied. Mercuric carboxylates were found to react with S-alkylthioamidium iodides giving the corresponding acid anhydrides and amides in good yields along with alkylmercaptomercuric iodide. In addition, it was established that the reaction of mercuric cyanide with the iodides afforded α-dimethylaminomalononitriles by the elimination of alkylmercapto mercuric iodide. Further, α-morpholino-β-phenylacrylonitrile was obtained in 87% yield by treating S-ethylthiophenylacetomorpholidium iodide with silver cyanide.
Reaction of Allylbenzene with n-Butyllithium in Tetrahydrofuran
Authors: Okamoto Yoshio , Yuki Heimei
Published: July 2006

The reaction products between allylbenzene and n-butyllithium in tetrahydrofuran at 60°C were fractionated and investigated by elementary analysis, a molecular-weight determination, and a study of the IR, UV, and NMR spectra. The products were hydrocarbons and alcohols, the latter of which were formed by the reaction of the carbanions with tetrahydrofuran. The main products were 3-phenylheptene-2,5-methyl-6-phenyldecane, 5-phenyl-5-heptene-1-ol, 5-phenyl-5-vinylnonane-1-ol, and 5-phenyl-5-vinylnonane-1,9-diol. 3-Phenylheptene-1 was not obtained. In the resonance structures of allyl anions, a and b, Ph-\barCR–CH=CH2 (a) ↔ Ph–CR=CH–CH2− (b), the reaction with tetrahydrofuran took place only in the form a. The observed results are correlated with those of the anionic polymerization of trans-β-methylstyrene reported previously.
Condensation of Methylolmelamine
Authors: Sato Kenji
Published: July 2006

The condensation of methylolmelamine in the range of ca. pH 8–1 was investigated. An aqueous-dimethylsulfoxide (DMSO) solution (ca. 1 : 2, vol. ratio) was mainly used as the solvent, because it was revealed that the condensate in the latter stage of the condensation is soluble in DMSO solvent, and also that in this solvent methylolmelamine scarcely decomposes into a lower methylolmelamine liberating formaldehyde; then, the condensation mechanism of that methylolmelamine whose composition corresponds approximately to di-, tri-, and hexa-methylolmelamine, was investigated, not only in the early stage but also in the latter stage. It was found that the condensation rates of di- and tri-methylolmelamines (low methylolmelamines) in the early stage show maxima at ca. [HGl]/[methylolmelamine]=0.5 (molar ratio), i.e., at ca. pH= logK, where K is the equilibrium constant between the molecular form of the methylolmelamine and its conjugate acid, and that in hexa-methylolmelamine (high methylolmelamine) the above maximum appears at ca. [HCl]/[methylolmelamine]=0.5–1.0 (molar ratio). Also, the above maxima were found to shift toward smaller [HGl]/[methylolmelamine] (molar ratio) values as the condensation proceeded (the latter stage). From these results, a condensation mechanism was proposed for the early stage of the condensation.
Scission Probabilities of the Skeletal Bond of Aliphatic Ethers by Electron Impact
Authors: Hirota Kozo , Takezaki Jun’ichi
Published: July 2006

Mass spectra of eight aliphatic mono- and di-ethers have been measured with apparatuses of both ordinary and high resolution type, and scission probability of their skeletal bonds has been determined. By application of the molecular orbital theory on bond-scission by electron impact, the scission probability of the skeletal bonds has been evaluated, using only a few constants peculiar to the C–O bond so as to determine the molecular orbital. Comparison between theory and experiment has been found satisfactory on such ethers, even though they have lone-pair electrons in the inner part of the molecules. Thereby, scission of the skeletal bond has been shown explainable quite well by the primary processes in most ethers, except highly symmetric or large ethers.
Thermal Decomposition of Hexamethylene Tetramine
Authors: Iwakami Yoshitomo , Takazono Masao , Tsuchiya Toshikazu
Published: July 2006

In order to get information about the mechanism of the thermal decomposition of hexamethylene tetramine (hexa), hexa was decomposed thermally in a vacuum vessel, and the composition of the gas thus produced was determined with a mass spectrometer. The main products found were ammonia and a carbon-rich solid residue. The carbon in the carbon-rich residue seems to act as a catalyst for the decomposition.