bluuebunny/crossref_metadata_2025 huggingface dataset:
Cotton Effect Induced in Optically Inactive Molecules and Molecular Complexes by Optically Active Environment. I. Pyrene, TCNNQ, and Their Molecular Complex in Acetylcellulose Film
Authors: I’Haya Yasumasa J , Yunoki Toru
Published: July 2006

Ultraviolet absorption spectra, induced optical rotatory dispersion and circular dichroism of pyrene, TCNNQ, and their molecular complex were measured in acetylcellulose film and solution. The Cotton effect corresponding to each absorption maximum of these systems appeared. A perturbation of excited states of these molecules and their complex due to an asymmetric environment of acetylcellulose might be of paramount importance in producing a non-zero rotational strength in the corresponding molecular absorption region. The second charge-transfer band was clearly detected in the differential optical rotatory dispersion spectrum of the TCNNQ-pyrene molecular complex embedded in an acetylcellulose film. The method was shown to be promising in detecting very weak and closely overlapped transitions in various molecules.
Activity Coefficients for the System Glycylglycine–Urea–Water
Authors: Uedaira Hatsuho
Published: July 2006

Activity coefficients for the ternary system glycylglycine-urea-water were measured by the isopiestic vapor pressure method at 25°C. The activity coefficients of glycylglycine were lowered by urea. The lowering increased with increasing concentration of urea and with decreasing concentration of the amino acid. It was dependent on amino acid concentration to a greater extent than in the system α-amino-n-butyric acid–urea–water. The activity coefficients of urea were also decreased by glycylglycine. The free energy of the transfer of glycylglycine from water to urea solutions in various concentrations was calculated. The values obtained were combined with enthalpy data to yield −3.9 e. u. as the entropy value for the transfer from water to 6 m urea solution. Results have been interpreted to support the existence of interaction between urea and glycylglycine.
Formation Constants of Some Bivalent Metal Chelates of N-Phenylbutyrohydroxamic Acid
Authors: Shukla J P , Tandon S G
Published: July 2006

The formation constants for the metal chelates of Mn(II), Ni(II), Zn(II), and Cu(II) with N-phenylbutyrohydroxamic acid have been determined in 50 volume per cent dioxane-water mixture following the Bjerrum-Calvin pH titration technique and maintaining the titration medium at a constant salt background (0.1 m KClO4) and a temperature 25±0.1°C. The formation constants found are logK1=9.68(Cu), 6.85(Zn), 6.67(Ni), 5.25(Mn), and logK2=8.58(Cu), 5.52(Zn), 5.21(Ni), and 4.09(Mn), the stability order being Mn<NiZn.
Studies of Ruthenium Complexes. III. Kinetics of Isotopic Ligand-Exchange Reactions of Halogenopentaammineruthenium(III) Complexes in Aqueous Solution
Authors: Shinohara Tetsuo , Yamada Takato , Takebayashi Noriyuki , Hiraki Shun-ichi , Ohyoshi Akira
Published: July 2006

Kinetic studies of isotopic ligand-exchange reactions, [Ru(NH3)5X]2++X*−=[Ru(NH3)5X*]2++X−, where X=Cl, Br, and I, have been made in aqueous solutions. The effects of the hydrogen- and halide-ion concentrations, and of the ionic strength of the aqueous solution on the exchange rate had not been observed under certain definite experimental conditions. The rate constants were determined to be 3.15×10−4 sec−1 for the chloro-pentaammine 3.63×10−4 sec−1 for the bromopentaammine, and 1.1×10−4 sec−1 for the iodopentaammine at 80°C. The energies of activation were 20 kcal/mol (chloropentaammine), 23 kcal/mol (bromopentaamine), and 30 kcal/mol (iodopentaammine). The reactions proceed through the following two steps:

[Ru(NH3)5X]2++H2O→[Ru(NH3)5H2O]3++X−

[Ru(NH3)5H2O]3++X*−→[Ru(NH3)5X*]2++H2O

The first step is regarded as the rate-determining one.
A Kinetic Study of the Monomer-dimer Reaction in Propionic Acid by Means of Ultrasonic Absorption Measurements
Authors: Tatsumoto Nobuhide , Sano Takayuki , Yasunaga Tatsuya
Published: July 2006

Second ultrasonic absorptions with relaxation frequencies of 26, 36, 53, and 70 MHz could be observed in 0.27, 0.47, 1.0, and 2.0 m cyclohexane solutions respectively of propionic acid at 20°C. The consideration of the variations in the sound absorption, the sound velocity, and the chemical shift with the concentration leads us to the conclusion that the relaxation is attributable to the perturbation of the equilibrium between the open dimer and the monomer of propionic acid. The backward rate constant in this reaction is estimated to be about 109 sec−1M−1.
Brominations of Aliphatic Ketones by Copper(II) Bromide in Organic Solvents. II. The Reaction of Acetone with Copper(II) Bromide in N,N-Dimethylformamide
Authors: Kojima Yoshitane , Usui Kimiko , Kawaguchi Shinichi
Published: July 2006

Because of a long induction period, the reaction between acetone and copper(II) bromide does not occur readily in pure DMF. However, in the presence of an acid, it proceeds readily. The initial rate is proportional to the product of the concentration of acetone and perchloric acid, but independent of the concentration of copper(II) bromide. The acid-catalyzed bromination of acetone by bromine has also been studied in DMF and found to obey the same second-order rate law as that in water. Both bromination reactions of acetone in DMF by copper(II) bromide and bromine were interpreted to be controlled by the enolization process of acetone.
Effects of Substituents on the Smiles Rearrangement of O-s-Triazmyl-2-aminophenoIs
Authors: Maeno Norio , Itagaki Takeshi , Uno Seiichi , Matsui Kohji
Published: July 2006

Several 4- or 5-substituted O-(s-triazinyl)-2-aminophenols were synthesized, and the kinetics of the Smiles rearrangement of these compounds have been studied spectrophotometrically in methanol, ethanol, and 2-propanol in order to make clear the effects of substituents on the rearrangement. Substituents in the s-triazine nucleus were found to affect the progress of the reaction to a great extent by changing the positive character of the triazine-ring carbon. On the other hand, a substituent in the aminophenol moiety affects both the nucleophilic reactivity of the attacking amino group and the stability of the leaving phenoxide anion or the reactivity of the s-triazinyl group, but the effect on the amino group was found to be predominant, the effect of a substituent in the aminophenol moiety was smaller than that of the substituents in the s-triazine nucleus.
Syntheses of Isoprenoids from Isoprene. III. The Dimerizations of Dimethylcyclopropanes
Authors: Tanaka Juntaro , Katagiri Takao , Takabe Kunihiko , Sakamoto Tadashi
Published: July 2006

1,1-Dimethylcyclopropane(I) was found to dimerize selectively by the action of boron trifluoride etherate. In the products, compound (III), which had been presumed, and the reaction intermediates (VII and VIII) were identified. The reaction mechanism was discussed. 1,2-Dimethylcyclopropane(VI) gave the same products.
Syntheses and Reactions of Functional Polymers. LXVI. Activation of Carboxylic Acid by Means of Polymers Containing Hydroxamic Acid Residue and N-Hydroxysuccinimide Residue
Authors: Narita Mitsuaki , Teramoto Takero , Okawara Makoto
Published: July 2006

In order to achieve solid-phase acyl activation of carboxylic acid, the syntheses and reactions of polymers containing hydroxamic acid and N-hydroxysuccinimide residues were investigated. A polymer containing hydroxamic acid residue was obtained by the modification of cross-linked copolymer of p-nitrophenyl acrylate with styrene, and one containing N-hydroxysuccinimide residue was prepared by copolymerization of N-acetoxymaleimide with styrene followed by hydrolysis. These N-hydroxy polymers were allowed to react with N-protected amino acids by means of the dicyclohexylcarbodiimide method giving the activated polymer ester. While the polymer containing hydroxamic acid residue was inferior to that containing N-hydroxysuccinimide residue in activation of carboxylic acid, amino acid esters of the latter were active enough to react with another amino acid to yield dipeptides almost quantitatively without racemization.
Oxidative Dimerization of Pyrrole Derivatives. II. The Formation and Structure of Dimers of 3-Alkoxycarbonyl-substituted Pyrryls
Authors: Tomita Kuniyuki , Yoshida Norio
Published: July 2006

Oxidation of 3-alkoxycarbonyl-substituted pyrrolic compounds with aqueous potassium ferricyanide in the presence of potassium hydroxide afforded 2,2′- and 5,5′-bispyrrolenine derivatives, which were in equilibrium with each other in solution via radical intermediates. The substituent effects on the dimer formation will also be discussed in connection with the characters of the intermediate pyrryl radicals.
Syntheses and Reactions of Metal Organics. VII. Reactions of n-Butoxytitanium Chlorides with Saturated Cyclic Ethers
Authors: Yoshino Norio , Yoshino Takeshi
Published: July 2006

The reactions of n-butoxytitanium chloride, TiCln(OnBu)4−n (n=0,1,2,3,4), with 1,4-dioxane, tetrahydrofuran, and tetrahydropyran have been studied. No adducts have been isolated when n=0,1,but the compounds TiCl2-(OnBu)2·O(CH2CH2)2O, TiCl2(OnBu)2·C4H8O, TiCl2(OnBu)2·C5H10O, TiCl3(OnBu)·O(CH2CH2)2O, TiCl3(OnBu)·2C4H8O, TiCl3(OnBu)·2C5H10O, TiCl4·O(CH2CH2)2O, TiCl4·2C4H8O and TiCl4·2C5H10O have been isolated when n=2,3,4. Possible structures for these adducts were discussed on the basis of elemental analysis, IR spectra, NMR spectra, and molecular weights. The adducts undergo hydrolysis very quickly with moisture.
Linear Conjugated Systems Bearing Aromatic Terminal Groups. IX. Syntheses and Elctronic Spectra of α,ω-Di-1-anthrylpolyenes
Authors: Takeuchi Yasuhira , Akiyama Shuzo , Nakagawa Masazumi
Published: July 2006

Syntheses of α,ω-di-1-anthrylpolyenes have been carried out by the Wittig reaction for information on the role of aromatic terminal groups on the electronic spectral regularity of α,ω-diarylpolyenes. The reaction of phosphoranes derived from 1-anthrylmethyl-, 3-(l-anthryl)propenyl-, and 5-(1-anthryl)-pentadienyltriphenylphosphonium bromides with 1-formylanthracene, 3-(1-anthyrl)propenal, 5-(1-anthryl)pentadienal, and muconic aldehyde afforded a series of di-1-anthrylpolyenes (I1−6) by a proper combination of the phosphorane and the aldehyde moiety. Owing to the broading of absorption bands in the long wavelength region, no discussion could be made on the electronic spectral regularity.
Thiocyanoacetate. IV. The Reaction of Ethyl Thiocyanoacetate with Aromatic Aldehydes in the Presence of Thioureas
Authors: Kambe Satoshi , Hayashi Toshio
Published: July 2006

Ethyl thiocyanoacetate (1) reacts with anomatic aldehydes in the presence of N,N′-dialkylthiourea to give arylidene N,N′-dialkyl-N-thiocarbamoyl thiocyanoacetamides (3). On the other hand, the treatment of the ester (1) with benzaldehyde in the presence of thiourea or N-methylthiourea under the same conditions affords 5-benzylidene-2-imino-4-thiazolidinone (5a) or 5-benzylidene-3-methylthiazolidine-2,4-dione (6a).
An MO-Theoretical Study of the Decomposition of Hydroperoxides by Sulfonium Compounds and Some Nucleophiles
Authors: Ohkubo Katsutoshi , Kanaeda Hirokazu
Published: July 2006

The decomposition reactions of hydroperoxides (ROOH) by sulfonium compounds or some nucleophiles (sulfides, phosphites, and transition metal ions) were treated by the extended Hückel method, augmented by the use of d-orbitals. We obtained serveral findings. First, ROOH was more reactive to nucleophiles and was energetically more stable than (ROOH)2. Second, the order of the ability for the ROOH decomposition, sulfonium compounds>>sulfides>phosphites\gtrsimthiophene, was in good agreement with that of the AO populations of the nonbonding lone pair orbitals of the above compounds. Third, the distinguished ability of the sulfonium compound may be attributed to the contribution of the partially-occupied sulfur d-orbitals, in particular, the lowest unoccupied dz2-orbital; in the ROOH decomposition, these orbitals interact with the lowest unoccupied antibonding pσ-orbital of the O–O in ROOH at the Oβ atom in the direction of the O–O axis. Finally, it was concluded that the sulfur d-orbitals contribute to the long-range interaction (S–Oβ>3.0 Å) between ROOH and sulfonium compounds.
An MO Approach to the Interpretation of Organic Mass Spectra. I. Relative Bond Energy of the Molecule Ion by the Extended Hückel Method
Authors: Ogata Michihiko , Ichikawa Hiroshi
Published: July 2006

A method of comparing the relative bond energies is applied to the interpretation of the simple cleavage and the McLafferty rearrangement reactions in organic mass spectrometry. A qualitative correlation between the relative bond energy and the charge density at the highest occupied orbital is found. The behavior of the highest occupied and some lower vacant orbitals is discussed.
Competitive Adsorption of Polyvinylpyrrolidone with n-Alkyl Alcohols at the Mercury/Solution Interface
Authors: Yoshida Tadashi , Ohsaka Tetsuya , Iida Yasuo
Published: July 2006

Competitive adsorption of polyvinylpyrrolidone (PVP, \barM=10000) with n-hexanol, n-pentanol, or n-butanol was examined by observation of the differential capacity at the mercury interface in 1 n sulfuric acid. Adsorption of PVP coexistent with alcohol hardly differed from the single adsorption1) controlled by its diffusion. The competitive adsorption curve of C (differential capacity) vs.  t1⁄2 (adsorption time) was expected from the sum of the individual capacity depressions by the single adsorption at −0.5 or −0.6 V (SCE) and the expected curve of C  vs.  t1⁄2 was compared with the curve observed. The competitive behavior of alcohol coexistent with PVP was examined by the relation “θAlccom (coverage of coexistent alcohol) vs.  t1⁄2” at −0.5 or −0.6 V (SCE), where θAlccom was estimated from the difference between the differential capacities with and without PVP, in view of the fact that behavior of PVP is nearly independent of the coexistent alcohol. The results are discussed in terms of four types of models assumed for the competitive behavior of coexistent alcohols with different adsorbability. It is considered that the alcohol is replaced with PVP as soon as the latter reaches the interface by diffusion, the adsorption equilibrium of an alcohol being achieved immediately. The relation θAlccom=(1−θpvp)θAlc holds in the case of n-butanol coxistent with PVP, where θPVP, θAlc, and θAlccom are coverages due to the single adsorption of PVP and butanol and to the competitive adsorption of butanol, respectively. The tendency of alcohol to be replaced with PVP is inversely proportional to its adsorption coefficient. n-Butanol was most sensitive to the coexistence of PVP.
Studies on Intermolecular Complex Formation. II. Crystal Structure of Cytosine-N-Benzoylglycine Complx Monohydrate
Authors: Tamura Chihiro , Hata Tadashi , Sato Sadao , Sakurai Noriko
Published: July 2006

Many intermolecular complexes between N-acylamino acids and nucleotide bases have been found by means of X-ray powder diffractometry. Among these, the crystal structure of N-benzoylglycine cytosine complex monohydrate has been determined by the direct method. The crystal data are: a=18.71,b=7.11,c=18.37 Å, and β=144.0°. The space group is P21⁄c; Dobsd=1.37; Dcalcd=1.35 g/cm3. The final R factor was 0.131. In the crystal, a cytosinyl cation and a N-benzoylglycyl anion are joined by two NH···O hydrogen bonds, of which the shorter one is 2.652 Å long. Such a complex formation may exist in vivo.
The Adsorption of Polyvinylpyrrolidone at the Mercury/Solution Interface
Authors: Yoshida Tadashi , Ohsaka Tetsuya , Tanaka Shoji
Published: July 2006

The adsorption of polyvinylpyrrolidone (PVP), known as a water-soluble polymer, at the electrolyte/DME interface was examined by observing the differential capacity vs. the time relation, under conditions where the adsorption process was mainly controlled by diffusion. In the case of a relatively low bulk concentration and a short adsorption time, the adsorption rate of PVP at−500 mV(SCE) was controlled almost wholly by the diffusion of the adsorbate to the DME. The relation between the time required to attain the saturated adsorption and the bulk concentration was explained approximately by the Koryta equation, based on the linear diffusion. PVP showed no tendency to form multi-layers within the range of bulk concentrations and adsorption times observed. The maximum surface concentration of PVP decreased almost linearly with the increase in its mean molecular weight. The number of constitutive segments adsorbed per unit of area to form a monolayer at the interface was almost constant, independent of the mean molecular weight. The activation energy for the diffusion was found to be ca. 4.7 kcal/mol. On the basis of the results obtained, the configuration of PVP adsorbed at the interface was discussed.
Bond Alternation in Tropone as Studied by Gas Electron Diffraction
Authors: Ogasawara Makoto , Iijima Takao , Kimura Masao
Published: July 2006

Assuming a planar conformation with C2v symmetry, and using the estimated mean amplitudes of vibration, the bond alternation in tropone was confirmed. The average C–C and C=C distances were determined by the least-squares method to be 1.454±0.010 and 1.362±0.013 Å respectively; moreover, two probable sets of the structure parameters were obtained. On the basis of conformational arguments regarding the structures of related compounds, the following set of the bond lengths was preferred: C–H, 1.098±0.016 Å; C1–O, 1.225±0.012 Å; C1–C2, 1.445±0.012 Å; C2–C3, 1.364±0.012 Å; C3–C4, 1.462±0.012 Å; and C4–C5, 1.342±0.018 Å.
Behavior of Oxygen Species on the Nickel Oxide Catalyst Surface
Authors: Chaudhri Safee , Kera Yoshiya , Hirota Kozo
Published: July 2006

The 18O-oxidation of carbon monoxide was studied on nickel oxide catalysts, and the oxygen exchangeability with the oxide during the reaction was determined. The activities of three oxide samples, obtained under different preparation conditions, were compared. The samples were prepared at 350, 600, and 850°C; they are denoted as NiO-I, NiO-II, and NiO-III respectively. In the case of NiO-I, two kinds of oxygen species, weakly and strongly bound to the surface, were observed. Above 120°C, not only weakly but also strongly bound surface oxygen become reactive; however, the binding energy distribution was quite broad. Similar observations were made in the case of NiO-II, with a similar change above 170°C and with a sharp energy distribution. In contrast, for NiO-III, only a small percentage of the monolayer of the surface oxygen became active and exchangeable below 200°C, but above 250°C about three layers became activated. Models are proposed for the surface state of these oxides on the basis of the behavior of the surface oxygen.
Monolayers of Poly(methyl acrylate) Saponified Partially in Homogeneous and Heterogeneous Systems
Authors: Hironaka Seiichiro , Meguro Kenjiro
Published: July 2006

Poly (methyl acrylate) prepared by radical polymerization of methyl acrylate was saponified partially in acetone-water mixtures (5 : 2 and 100 : 1 by volume), using sodium hydroxide as the catalyst. Saponification in an acetone-water mixture of a 5 : 2 ratio by volume proceeded in a homogeneous state, but the reaction solution of a 100 :1 ratio by volume was in a white-turbid state, in which saponification proceeded in a heterogeneous state. The properties of the monolayers of polymers saponified in different states were studied at the air/water interface by measuring the surface pressure. The limiting areas obtained on distilled water for each polymer saponified in these two systems decreased linearly with an increase in the degree of saponification. However, the monolayers of polymer saponified in a homogeneous system were more stable on sodium chloride solution than those obtained in a heterogeneous system, and gave the limiting areas on solutions above 5% corresponding with the theoretical values calculated from the areas per methyl acrylate and acrylic acid residue and the degree of saponification. This can be explained by the fact that some of the hydrophilic parts of the saponified polymers submerged into the water phase were squeezed out onto the water surface by the salting out effect. On the other hand, those values obtained in a heterogeneous system neither corresponded to the theoretical values nor gave reproducible areas at high concentrations. These facts may be due to the differences in the states of the saponified polymers.
The Vibrational Assignment and Force Constants of Halogenomethylsilanes and Their Germanium Analogues: ClCH2SiH3, ClCH2SiD3, BrCH2SiH3, BrCH2SiD3, CICH2GeH3, and CICH2GeD3
Authors: Ohno Keiichi , Murata Hiromu
Published: July 2006

The infrared spectra of ClCH2SiH3, ClCH2SiD3, BrCH2SiH3, BrCH2SiD3, ClCH2GeH3, and ClCH2GeD3for both the gaseous and solid states in the 250–4000 cm−1 region have been obtained. All the fundamental vibrations except for the skeletal bending and YH3(–D3) (Y=Si, Ge) torsional vibrations have been observed and assigned. The normal vibration calculation has been carried out using a modified Urey-Bradley force field. The transferability of the force constants has also been investigated.
The Diffuse Reflection Spectra of 1-Arylazo-2-naphthols Deposited on Various Synthetic Fibers
Authors: Matsunaga Yoshio , Miyajima Nobuhiko
Published: July 2006

The diffuse reflection spectra of sixteen 1-arylazo-2-naphthols deposited on polypropylene, polyacrylonitrile, polyethylene terephthalate, and Nylon-6,6 were recorded in the range from 350 to 700 nm. The spectra indicate the coexistence of the azo and hydrazone tautomers in these systems. By a comparison with the absorption spectra of the compounds dissolved in n-hexane, acetonitrile, methyl benzoate, and formamide, it was concluded that the nature of the fibers is the major factor determining the tautomeric equilibria. The effect of moisture on the spectra was found to be rather small except in the cases of the p-OH and p-MeO derivatives deposited on polyacrylonitrile.
Measurements of Acid-strength Distribution beyond H0=−8.2 of Silica-Alumina Catalysts by UV-Spectrophotometric n-Butylamine Titration Method
Authors: Take Jun-ichiro , Tsuruya Tetsuo , Sato Tetsuo , Yoneda Yukio
Published: July 2006

A new UV-spectrophotometric n-butylamine titration method was proposed for measuring acid-strength distribution of acid sites on solid acid catalysts. The method can provide information on acid-strength distribution of acid sites beyond H0=−8.2, which can not be obtained by the conventional visual n-butylamine titration method. Acid-strength distributions were measured for a series of silica-alimina catalysts differing in sodium content, using 4-benzeneazodiphenylamine (pKa=1.5), trans-benzalacetophenone (pKa=−5.6), 4-nitrotoluene (pKa=−10.5), and 2,4-dinitrotoluene (pKa=−12.8) as indicators. The results revealed that about one-half of the acid sites on an unpoisoned silica-alumina catalyst lay in the H0 region from −10.5 to −12.8, and the strongest ones in the H0 region beyond −12.8. The strong acid sites were eliminated with the modification of acid-strength distribution as the catalyst was poisoned with sodium ions. UV spectra of the above indicators in adsorbed state were discussed.
Titrimetric Determination of Iron(II), Molybdenum(V), and Thallium(I) with Potassium Chlorate Using Redox Indicators
Authors: Rao G Gopala , Radhakrishnamurty C
Published: July 2006

Accurate and convenient procedures have now been devised for the titrimetric determination of iron(II), molybdenum(V), and thallium(I) with potassium chlorate using visual indicators. These procedures are more advantageous than the procedures involving bromate. Further, chlorate is to be preferred as it is more inexpensive than bromate or iodate. Potassium chlorate is now obtainable at the purity required of a primary standard at a nominal cost. The chlorate titration procedure for iron(II) works satisfactorily even in the presence of organic materials such as oxalic acid, tartaric acid, and citric acid, so that it can be used for the determination of ferrous iron in pharmaceutical preparations or of ferric iron after reduction. It has been observed by us that oxygen of the air interferes in the titration of iron(II) in 6–7m hydrochloric acid medium using naphthol blue black or methyl orange as a redox indicator but not in the titration of iron(II) in sulphuric acid medium using ferroin as an indicator. An inert atmosphere is not necessary for the titration of molybdenum(V) and thallium(I) in hydrochloric acid medium.
The Synthesis of 2,3-Dimethoxy-5-methyl-p-benzoquinone
Authors: Sato Kikumasa , Inoue Seiichi , Sato Haruhito
Published: July 2006

2,3-Dimethoxy-5-methylbenzoquinone, the key intermediate of the synthesis of coenzyme Q, was synthesized via two new routes. The methylation of 5-nitrovanillin gave 5-nitroveratraldehyde, which was then catalytically reduced to afford 5-aminohomoveratrol. The oxidation of 5-aminohomoveratrol gave 2,3-dimethoxy-5-methylbenzoquinone. 2,3,4-Trimethoxyphenol was obtained by the decarboxylation of 3,4,5-trimethoxysalicylic acid. This was converted via Mannich reaction to 2,3,4-trimethoxy-6-methylphenol, which was then easily oxidized to 2,3-dimethoxy-5-methylbenzoquinone.
Elektrochemische Untersuchungen über den Litheffekt
Authors: Suga Tsuneo
Published: July 2006

Es wurde der Mechanismus des Litheffektes diskutiert. Um dieses Problem zu behandeln, wäre es nützlich, daß man sich den Litheffekt in Verbindung mit Lithemulsion und Lithentwickler überlegt. Nach Yule beschleunigen die bei der Entwicklung entstandenen Oxydationsprodukte des Hydrochinons die Lithentwicklung. In der vorliegenden Arbeit wurde die Rolle der Oxydationsprodukte weiter vom Standpunkt der Oxydation aus elektrochemisch untersucht. Die Oxydationsprodukte beschleunigen die Entwicklung der stärker belichteten Körner durch die Herabsetzung des Ladungsbarriereeffektes und hemmen die Entwicklung der schwächer belichteten Körner durch die Oxydationsfähigkeit. Wenn diese beiden Faktoren miteinander ins Gleichgewicht gebracht werden, könnte man einen guten Litheffekt erhalten. Nach dieser Ansicht konnte man die Ursache für den guten Litheffekt einer Lithemulsion gut erklären.
Adsorption of Sodium and Calcium Dodecyl Sulfates at the Surface of Their Aqueous Solutions
Authors: Sasaki Jun , Tajima Kazuo , Sasaki Tsunetaka
Published: July 2006

Adsorption of sodium dodecyl sulfate (NaDS) and calcium dodecyl sulfate (Ca(DS)2) at the aqueous surface was measured by a radiotracer method using tritium labelled compounds at constant ionic strength of 1×10−2 and 7.5×10−3 adjusted by the addition of NaCl and CaCl2, respectively. The adsorbed amounts increased with increasing concentration of dodecyl sulfates in both cases, and approached saturation values of 3.65×10−10 mol/cm2 at 25°C for NaDS and 3.8×10−10 mol/cm2 at 55°C for Ca(DS)2. The amounts calculated from surface tension data by applying the Gibbs adsorption isotherm were confirmed to be in good agreement with the values directly measured. The adsorbed amounts of chloride ion, generally assumed to be zero, were confirmed to be negligible in the concentration region from zero up to critical micelle concentration.
Study of Dielectric Relaxation Mechanism and Mutual Viscosity in Some Aromatic Compounds
Authors: Mehrotra N K , Pant T C , Saxena M C
Published: July 2006

Relaxation time and mutual viscosity of seven substituted benzenes, p-toludine, o-nitroaniline, 2,4-dichloroanisole, 2,3-dichloroanisole, 2,5-dichloronitrobenzene, 3,4-dichloronitrobenzene, and 4-chloro-1,3-dinitrobenzene have been determined in the 3.13 cm (9585 MHz) microwave region, and at three different temperatures 20, 30, and 40°C. Correlation of mutual viscosity with relaxation time leads to the conclusion that the mutual viscosity is a better representation of the resistance to the rotation of the individual solute molecule.
Solvent Effects under High Pressures. IV. A Procedure for the Estimation of Solvation in the Transition State
Authors: Kondo Yasuhiko , Ohnishi Masaru , Tokura Niichiro
Published: July 2006

The rate constants and activation parameters were measured for the reaction of pyridine with benzyl bromide in various solvents. The rate constants were better correlated to the activation volumes than to the activation entropies. The linear free-energy relationships were observed in the plots of the logk values of some Menschutkin reactions vs. the logk values of the present reaction in various solvents. Corresponding to their good correlations between the values of log k and of their pressure derivatives for the present reaction, the values of (z·ΔP), which are the slopes of the plots of ΔV0\eweq  vs. KV0, increased with the increase in the slopes of the above linear free-energy relationships. The activation volumes in various solvents are linearly correlated to their pressure derivatives. An equation which predicts the relationship has been derived. Using this equation, the solvation number in the activated complex and the average pressure within its cosphere have been estimated to be ca. 4 and 910 (kg. cm−2) respectively. Based on these results, discussions have been given on the solvation in the transition state for the present reaction.
Studies of Acyl and Thioacyl Isocyanates. X. The Cycloaddition Reaction of Benzoyl and Thiobenzoyl Isocyanates with Benzaldazines
Authors: Tsuge Otohiko , Kanemasa Shuji
Published: July 2006

Although benzoyl isocyanates do not react with benzaldazines at room temperature, the criss-cross cycloadducts are formed if the reaction is carried out in refluxing xylene. On the other hand, thiobenzoyl isocyanate behaves quite differently toward the same azines. It reacts easily with azines at room temperature to afford to mono- or the bis(4+2) cycloadducts depending on the nature of the substituent in the azines. We found that the mono (4+2) cycloadduct can be thermally dissociated into its components. Neither benzoyl isocyanate nor thiobenzoyl isocyanate react with aromatic ketazines.
Studies on Nitro Carboxylic Acids. II. Synthesis of α,β-Unsaturated β-Nitro Carboxylic Esters
Authors: Shin Chung-gi , Yonezawa Yasuchika , Narukawa Hirotoshi , Nanjo Katsumi , Yoshimura Juji
Published: July 2006

Synthetic studies on ethyl α,β-unsaturated β-nitrocarboxylates (IV) through two routes are described. Ethyl α-hydroxy-β-nitrocarboxylates (II) obtained by the reactions of ethyl α,β-unsaturated carboxylates with fuming nitric acid or by those of nitroparafins with ethyl glyoxylate, were treated with acetic anhydride to afford ethyl α,-acetoxy-β-nitrocarboxylates (III), which were subsequently converted into IV by treatment with bases used as catalysts. On the other hand, IV was also obtained from ethyl α-chloro-β-nitrocarboxylates derived from the reactions of ethyl α,β-unsaturated carboxylates with nitryl or nitrosyl chloride. The structural assignments of IV were made on the basis of elementary analysis, infrared spectra and its conversion into the corresponding α-methoxy derivatives.
Studies on Amino-hexoses. XV. Synthesis of Deoxy-N-acetyl-muramic Acid
Authors: Arita Hitoshi , Fukukawa Kiyofumi , Matsushima Yoshio
Published: July 2006

Benzyl 2-acetamido-6-O-acetyl-4-chloro-2,4-dideoxy-3-O-[d-1-(methyl carboxylate)ethyl]-α-d-galactopyrano-side and benzyl 2-acetamido-4,6-dichloro-2,4,6-trideoxy-3-O-[d-1-(methyl carboxylate) ethyl]-α-d-galactopyranoside were prepared by the reaction of sulfuryl chloride on N-acetyl-muramic acid derivatives. 2-Acetamido-2,4-dideoxy-3-O-(d-1-carboxyethyl)-d-xylohexo-pyranose (N-acetyl-4-deoxy-muramic acid) and 2-acetamido-2,4,6-trideoxy-3-O-(d-1-carboxyethyl)-d-xylohexo-pyranose (N-acetyl-4,6-dideoxy-muramic acid) were prepared by the reduction of these chlorodeoxy derivatives with tri-n-butyltin hydride.
Studies on Aminosugars. XXXII. Synthesis of 3′, 4′-Dideoxykanamycin B
Authors: Umezawa Sumio , Umezawa Hamao , Okazaki Yasushi , Tsughiya Tsutomu
Published: July 2006

Penta-N-ethoxycarbonylkanamycin B (1) prepared from kanamycin B was treated with 2,2-dimethoxypropane in DMF to give a 3′,4′;4″,6″-di-O-isopropylidene derivative (3). Subsequent benzoylation afforded a 2″-O-benzoyl derivative (4), Removal of the isopropylidene groups from 4 followed by controlled isopropylidenation afforded the corresponding 4″,6″-O-isopropylidene derivative (5), which was then transformed to a 3′,4′-di-O-mesyl derivative (6). Treatment of 6 with sodium iodide and zinc dust in DMF gave the desired 3′,4′-unsaturated derivative (7). Hydrogenation and removal of the protecting groups gave the title compound. The 3′,4′-dideoxykanamycin B expectedly showed remarkable activity against kanamycin-resistant bacteria as well as sensitive strains.
Linear Conjugated Systems Bearing Aromatic Terminal Groups. X. Syntheses and Electronic Spectra of α,ω-Di-1-naphthyl- and α,ω-Di-2-naphthylpolyenes
Authors: Yasuhara Akio , Akiyama Shuzo , Nakagawa Masazumi
Published: July 2006

Syntheses of di-1-naphthyl- and di-2-naphthylpolyenes (In, n=1–4,6 and In′, n=1–6) have been carried out by the Wittig reaction. Naphthaldehydes (III and III′), 3-naphthyl-2-propenals (V and V′), 5-naphthyl-2,4-pentadienals (VI and VI′) and muconic aldehyde were used as carbonyl components. Naphthylmethyltriphenylphosphonium halides (IV and IV′), 3-naphthyl-2-propenyltriphenylphosphonium bromides (XI and XI′) and 5-(2-naphthyl)-2,4-pentadienyltriphenylphosphonium bromide (XII′) were synthesized and converted into the corresponding phosphoranes by reaction with phenyllithium. The reaction of carbonyl moiety with phosphorane by a proper combination afforded dinaphthylpolyenes (In and In′). The electronic spectra of di-1-naphthylpolyenes (In) showed broad and structureless absorption curves. In contrast, the absorption curves of di-2-naphthylpolyenes (In′) exhibited a distinct vibrational fine structure. It was found that the bathochromic shift of the longest-wavelength peak (λmax) along with the increase of the number of double bond (n) can be expressed by the following empirical formula:

λmax=45.4n0.7+302 (nm in tetrahydrofuran)
Optically Active Triptycenes. II. Synthesis of Optically Active 7-Substituted 2,5-Dimethoxytriptycenes
Authors: Ogura Fumio , Sakata Yoshiteru , Nakagawa Masazumi
Published: July 2006

A series of optically active 7-substituted 2,5-dimethoxytriptycenes has been prepared from (+)-2,5-diacetoxy-7-carboxytriptycene (I) as suitable model compounds for a study of the relationship between their structure and optical rotatory properties. The single crystal of 2,5-dimethoxy-7-dimethylaminotriptycene hydrobromide (VII) thus prepared was subjected to X-ray crystallographic analysis and proved to have 1R, 6S absolute configuration. Consequently, it became clear that all compounds of this series have the same 1R, 6S configuration. They showed without exception positive optical rotation in visible wavelength region.
The Allylic Rearrangement. II. Reactions of 5,5,5-Trichloro-3-penten-2-one with Nucleophiles
Authors: Takeda Akira , Tsuboi Sadao , Moriwake Takashi , Hirata Eiji
Published: July 2006

Reactions of 5,5,5-trichloro-3-penten-2-one (1) with a number of nucleophiles have been carried out. It was found that the Grignard reagents (5) primarily attacked the carbonyl carbon of 1 yielding the corresponding tertiary alcohols (7). The reaction sequence of ethylmagnesium bromide (5a) is given as an example. The reaction of 5a with 1 gave 6,6,6-trichloro-3-methyl-4-hexen-3-ol (7a) as the major constituent of the primary product. The hexenol 7a readily underwent the allylic rearrangement by heating at distilling temperature (88–90°C/6 mmHg) to afford 4,6,6-trichloro-3-methyl-5-hexen-3-ol (8a), which was in turn converted into 6,6-dichloro-3-methyl-3,4-epoxy-5-hexene (9a) by treatment with sodium methoxide. The stereoselective synthesis of dl-erythro-4,6,6-trichloro-3-methyl-5-hexen-3-ol (8a-I) was achieved by using 3,5,5-trichloro-4-penten-2-one (3) as the starting material in place of 1. dl-trans-6,6-Dichloro-3-methyl-3,4-epoxy-5-hexene (9a-I) was derived by the cyclization of 8a-I with a base. The stereochemistry of 8a and 9a was discussed on the basis of NMR data. Nucleophiles such as methanol, hydrogen chloride, anilines, thiophenol, sodium acetate, sodium phenolate, and diethyl sodiomalonate gave the products of the conjugate addition (15). Ethyl sodioacetoacetate gave 2-chloro-3-acetonyl-4-ethoxycarbonyl-5-methylfuran (17).
The Acid-catalyzed Degradation of Methyl 2,3,4,5-Tetra-O-acetyl-α-l-xylo-2-hexulopyranosonate. A Model for the Degradation of l-xylo-Hexulosonic Acid
Authors: Goshima Kazuaki , Maezono Norihide , Tokuyama Kanji
Published: July 2006

The degradation reaction of l-xylo-hexulosonic acid (1) was studied, using methyl 2,3,4,5-tetra-O-acetyl-l-xylo-2-hexulopyranosonate (11) as a model compound. The degradation of 11 proceeded via two pathways, 11→α,β-unsaturated ketone compound→a furan compound (path a) and 11→a dihydropyrone compound→further decomposed products (not furans) (path b). The major pathway was path a in benzene and path b in water. The results supported the idea that the acid-catalyzed degradation of l-ascorbic acid (2) to furans would not proceed via  1, but directly.
High Modulus Carbon Fibers from Pitch Materials
Authors: Otani Sugio , Watanabe Shoji , Ogino Hosaku , Iijima Kazuo , Koitabashi Teruyo
Published: July 2006

Preparation of high modulus carbon fibers from pitch materials was attempted by two methods, stretchgraphitization and the use of a special pitch material composed of highly oriented constituent molecules. It was shown that carbon fiber of high tensile strength and of high modulus can be prepared by stretch-graphitization, and high modulus carbon fiber by heat treatment without stress from the pitch of tetrabenzophenazine. The property of precursor was found to have an important effect on the structure of the fiber.
Study of Grinding Reaction of the System of Fine Particle Silica and Basic Zinc Carbonate by X-Ray Silicon K-Emission Band Spectra
Authors: Motoyama Muneyuki , Hashizume Genzo
Published: July 2006

Usefulness of X-ray emission spectrometry was demonstrated in a study of the grinding reaction of the system of fine particle silica and basic zinc carbonate. SiKα bands of the ground mixtures shifted toward the lower energy side relative to that of the fine particle silica, whearas SiKβ bands toward the opposite side. These band shifts were regarded as a measure of the reaction progress. The SiKβ band shift was shown more distinctly than the Kα band shift and explained as come from a decrease in the s-character of the bond caused by the chemical bonding of the zinc atom with the fine particle silica. The Kβ band shift was also correlated with the destabilization energy relative to the fine particle silica after C. G. Dodd and G. L. Glen. The band shifts indicated that the final product of this grinding reaction was amorphous zinc silicate-like compound. The correspondence of the X-ray band shifts with the infrared spectral shifts was also shown.
Geometrical Structures of Excited States of Conjugated Molecules: Benzene, Naphthalene, Azulene, and Heptalene
Authors: Fujimura Yuichi , Yamaguchi Hiroyuki , Nakajima Takeshi
Published: July 2006

A semiempirical SCF CI MO method used in combination with the variable bond-length technique, which has proved to be quite successful in predicting the ground-state geometrical structures of conjugated molecules, has been applied with modifications suitable to their excited states. The values of the parameters appearing in the expression of the resonance integral were adjusted so as to reproduce both the absorption and fluorescence spectra of benzene. The lower three singlet states (1B2u, 1B1u, and 1E1u) and the lowest triplet state (3B1u) of benzene, the lower two singlet states 1B1u and 1B2u) of naphthalene, the lower two singlet states (1B2 and 1A1) of azulene, and the lowest singlet state of heptalene are examined. It is predicted that the 1B1u and 3B1u states of benzene have the antiquinoidal and quinoidal conformations of the D2h symmetry respectively, and that the symmetry of the lowest singlet state of heptalene is higher than that (C2h) of the ground state.
The Effects of the Crystal-structural Transformation on the Chemical Behavior of 64Cu Recoil Atoms in α-Copper Phthalocyanine
Authors: Kudo Hiroshi
Published: July 2006

The Stage-II annealing process of 64Cu recoil atoms in neutron-irradiated α-copper phthalocyanine was carefully examined. The isothermal annealing curve above 270°C showed anomalous inflection point. It was found that the Stage-II annealing process of the α-crystal consisted of a “normal” monotonous annealing process and a “delayed” process caused by the crystal-structural transformation. The results of a kinematic analysis suggested that the fluctuation of the matrix and the change in the crystalographic factors due to the structural transformation play a triggering role in the delayed annealing reaction.
Semiconducting Anion-radical Salts Derived from 3,3′5,5′-Tettrahalo-p-diphenoquinones
Authors: Matsunaga Yoshio , Narita Yoshihiro
Published: July 2006

3,3′5,5′-Tettrahalo- and 3,3′,5,5′-tetrabromo-p-diphenoquinones were found to form series of complex anion-radical salts of the M+(Q2)− or M+2(Q3)2− type with various onium cations. These complex salts are darkcolored, almost black in many cases, and show electronic absorptions extending into the rock-salt region. In addition, bluish green-colored simple salts could be isolated with a few cations. The complex salts exhibit electrical resistivities in orders from 10 to 104 ohm cm at room temperature. Neither the pattern due to the quinone molecule nor that due to the semiquinone ion is present in their vibrational spectra. A single carbonyl stretching vibration band appears around 1600 cm−1, intermediate between that in the quinone and that in the semiquinone salt.
Distribution Studies of Alkali Metal Picrates
Authors: Iwaghido Tadashi
Published: July 2006

Alkali metal picrates are extractable from an aqueous solution into nitrobenzene. The picrates exist mainly as the dissociated form in both the aqueous and the nitrobenzene phases, whereas picric acid exists mainly as the undissociated form in the organic phase. The distribution ratio of the picrates and picric acid at any pH can well be explained in terms of these equilibrium constants. The distribution coefficient of picric acid is evaluated to be 102.63.
Kinetics and Mechanisms of the Reaction of Fe(III) with Variamine Blue, [N-(p-Methoxyphenyl)phenylenediamine] in Aqueous Perchlorate Media
Authors: Imamura Taira , Fujimoto Masatoshi
Published: July 2006

The kinetics of the non-complementary reaction of Fe(III) with Variamine Blue was studied under nitrogen atmosphere in perchlorate media of ionic strength μ=1.0m. The iminoquinone form of Variamine Blue was followed spectrophotometrically by a stopped-flow technique. The rate constants of the stepwise reaction, Fe(III)+(V.B.) \oversetkα\ightleftarrows Fe(II)+(V.B.)sox, Fe(III)+(V.B.)sox \oversetkβ→ Fe(II)+(V.B.)ox+2 H+, were evaluated to be kα=3.28×102 and kβ=4.29×102  m−1 sec−1 at pH\simeq2.2 and 25°C. The apparent activation energy was 10±1 kcal·mol−1 for both kα and kβ. The formation rate was not seriously affected by hydrogen ion concentration (pH 2.2–0.77).
Complexes Coordinated by 2,2′-Bipyridine Negative Ion. II. Sodium 2,2′-Bipyridinetetracarbonylchromium, -molybdenum, and -wolfram
Authors: Kaizu Youkoh , Kobayashi Hiroshi
Published: July 2006

Bipyridinetetracarbonylchromium, -molybdenum and -wolfram and their related complexes were reduced with sodium metal in tetrahydrofuran. Some products in the first stage of reduction were isolated. On the basis of the electronic absorption spectrum and the electron spin resonance, the complex formed in the reduction was concluded to be a complex coordinated by mononegative ion of bipyridine. Metal dσ orbital in the complex is still higher than bipyridine π* orbital, even if it is fairly lowered by a positive charge arising from the “metal to carbonyl” back-donation. Trapped electrons in the bipyridine π* orbital are, however, readily transferred into dσ orbital depending upon molecular environment. This gives rise to the formation of a pentacoordinate complex or complex dimer evolving carbon monoxide.
Studies on New Derivatives of 8-Quinolinol as Chelating Agents. I. Syntheses, Coloration Reaction with Metal Ions and Acid Dissociation Constants of Some Azomethine and Aminomethyl Derivatives
Authors: Hata Takehisa , Uno Toyozo
Published: July 2006

Azomethine derivatives of 8-hydroxyquinoline-2-carbaldehyde with aromatic and aliphatic amines and their aminomethyl derivatives were synthesized for the purpose of investigating their applications as analytical reagents. Spot tests with metal ions revealed that azomethine derivatives form intensely colored chelates, whereas aminomethyl derivatives form less intensely colored chelates. The acid dissociation constants were determined by means of potentiometric titration in 50 v/v% aqueous dioxane solution at 25±0.1°C. The values of pKNH+ and pKOH of 8-hydroxyquinoline-2-carbaldehyde, 2-(o-hydroxyphenylaminomethyl)-, 2-(p-chlorophenylaminomethyl)-, 2-(p-tolylaminomethyl)- and 2-(naphthylaminomethyl)-8-quinolinol are lower than those of 8-quinolinol. The phenyl substituent in 2 position of oxine moiety exerts an acid strengthening effect on these ligands. The basicity of the ligand N,N′-bis- (8-hydroxy-2-quinolylmethyl)ethylenediamine is higher than that of other oxine derivatives.
Synthetic Reactions by Complex Catalysts. XXIV. A New Catalyst of Copper-Isocyanide Complex for the Michael Addition
Authors: Saegusa Takeo , Ito Yoshihiko , Tomita Shimpei , Kinoshita Hideo
Published: July 2006

It has been found that some binary systems of a copper compound (or metallic compounds) and an isocyanide catalyze the Michael addition reaction. As the copper component, Cu2O, metallic copper and copper acetylacetonate are effectual, whereas CuCl, CuCl2, and CuO are ineffectual. The catalyst of copper isocyanide complex is characterized by the selective activation of cyano olefin compounds such as acrylonitrile. This was demonstrated by the competitive addition of an active hydrogen compound to acrylonitrile and methyl acrylate. Some results of kinetics and spectroscopic studies have been explained by assuming a scheme involving coordination of olefin onto copper-isocyanide complex.
Reaction of Enol Ethers with Carbenes. X. Ring Opening of 2,2-Dichlorocyclopropyl Phenyl Sulfides
Authors: Parham William E , Kajigaeshi Shoji , Groen Siemen H
Published: July 2006

The ring opening reactions of six known or new 2,2-dichlorocyclopropyl phenyl sulfides have been carried out with potassium t-butoxide in t butyl alcohol and with pyridine. The products were enynes, butadienes, allenes and, as minor products, α,β-unsaturated aldehydes containing the phenylmercapto group. Reaction of a mixture of cis- and trans-1,1-dichloro-2-methyl-3-phenylmercaptocyclopropane (2) with pyridine gave unchanged trans-isomer. This apparent selectivity is explained on the basis of the steric effects for ring opening.
The Reaction of Diaryl Disulfides with the Cyanide Ion
Authors: Tanaka Kazuhiko , Hayami Jun-ichi , Kaji Aritsune
Published: July 2006

The reaction of symmetrical disulfides with the cyanide ion in various solvents has been investigated. The reaction modes may be summarized as follows: (1) Dialkyl disulfides and diaryl disulfides with electron-with-drawing substituents react with the cyanide ion in DMSO or DMF to give the corresponding monosulfides. (2) Diaryl disulfides with electron-donating substituents react with DMSO to yield aryl methyl sulfides. (3) Diaryl disulfides are cleaved by the cyanide ion into thiolate anions and aryl thiocyanates, which then react with alcohol to afford alkyl aryl sulfides.