bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Molecular Orbitals Study of the Nucleophilic Substitution in Methyl Chloride
Authors: Kato Hiroshi , Morokuma Keiji , Yonezawa Teijiro , Fukui Kenichi 
Published: July 2006

Abstract
The electronic structures of CH3C1 and a “transient” species (Cl…CH3…Cl)− have been calculated by an extended Hückel method. The calculated results of CH3C1 correlate well with the experimental facts. The main features of the electronic structure of (Cl…CH3…Cl)−-may be summarized as follows:
1) The 3py orbitals of the chlorine atoms and the 2py orbital of the central carbon atom (pσ-orbitals) play an important role in the interaction between the C–Cl bonds.
2) The 2s orbital of the central carbon atom at the symmetrical configuration makes no contribution to the C–Cl bonding; rather, this orbital, together with the 2px and 2pz orbitals, participates in the C–H bonding.
3) The 3px and 3pz orbitals of the chlorine atoms form the lone-pair orbitals.
The natures of the MO’s of the symmetrical configuration have also been briefly discussed.
It should be noticed, however, that the present treatment is not yet sufficiently qualified as a method to allow an interpretation of the stable configuration of a molecular system, since it does not explicitly take into account the nuclear repulsion and the electronic interaction. Accordingly, there remains room for criticism with respect to the theoretical significance which the configuration of such a local minimum will have in the true electronic process on the reaction path. This point will be examined further in the future.
The Extraction of Thallium(III) from Hydrochloric Acid Solutions with Ethyl Acetate
Authors: Srivastava T N , Rupainwar D C 
Published: July 2006

Abstract
Ethyl acetate has been employed as a solvent for extracting thallium(III) from its hydrochloric acid solutions. The empirical formula of the extracted metal entity has been found to be HTCl4. Optimum conditions for the extraction of the metal have been determined, and the effect of various factors, e.g., metal concentration, salting-out agents, and the dilution of the solvent, have been investigated. It has been possible to separate thallium(III) from aluminum(III), gallium(III) and indium-(III) by performing a batch-by-batch extraction at a 1.0 n hydrochloric acid concentration.
1) The extracted species is an acid with an approximate formula of HTICl4, the distribution of the species between the two phases depends upon the concentration of the hydrochloric acid present in the system.
2) The extracted species is ionic and may associate in the organic phase to from ion pairs, ion triplets and higher clusters. This is evident from the fact that an increase in the metal concentration causes an increase in the distribution coefficient.
3) There is no primary solvation of thallium, which is tetrahedrally surrounded by chloride ions and which is apparently saturated. This is supported by the observation that the metal could not be extracted from its solution in perchloric acid.
4) The proton of the chlorothallic acid may be solvated (and possibly hydrated, too) in the organic phase, the solvation number being indefinite.
5) Ion pairing results in the formation of an extractable complex and a general mechanism of the type:
H(S)++[TlS)2C14]−\ightleftharpoons[(HS+)(Tl(S2)C14)−]
may be expected, where S is either H2O or ethyl acetate.
The above equation may well represent qualitatively various reactions at different relative water and ethyl acetate activities.
In general, the system is a simple ion-association extraction system and is quite similar to the extraction of iron(III) and gallium(III) chloride with oxygenated solvents.
Effect of the N-Substituent on the Course of the Reaction of α-Aminonitriles with Organometallic Reagents
Authors: Yoshimura Juji , Ohgo Yoshiaki , Sato Tetsuo 
Published: July 2006

Abstract
The reactions between various N-substituted-α-aminonitriles and organometallic reagents have been investigated in order to clarify the effect of the N-substituent on the reaction course.
The results indicate that:
(1) Both Grignard reagent and lithium alkyl attack not nitrile carbon but α-carbon to give substituted product when the α-aminonitrile has an active hydrogen on its aminonitrogen.
(2) In the case of α-dialkylaminonitriles, Grignard reagents attack the α-carbon to give substituted products, but lithium alkyls attack the nitrile carbon.
(3) The aminonitriles bearing acetyl group on its aminonitrogen are not attacked at α-carbon but at nitrile carbon by both the reagents, thus giving addition products.
The Catalytic Effect of the Support on Terpene Compounds in Gas-Liquid Chromatography
Authors: Hayashi Shûichi , Yano Katsumi , Yokoyama Naruo , Matsuura Tamon 
Published: July 2006

Abstract
The catalytic action of several solid supports, that is, glass, rock crystal, quartzite, sea sand, unglazed porcelain and commercial supports, have been examined. Glass shows practically no catalytic action in the examined terpene compounds, except for linalyl acetate and α-santalol, which were decomposed and/or isomerized slightly, but this support does show an adsorption of oxygen-containing compounds. The catalytic action of rock crystal is slightly greater than that of glass, but the adsorptivity of rock crystal is extremely small. Commercial diatomaceous earth supports show a remarkable catalytic action.
The Preparation of Hydride-free Triethylaluminum and Its Reaction with Titanium Tetrachloride
Authors: Takashi Yukichi , Aishima Itsuho 
Published: July 2006

Abstract
Hydride-free triethylaluminum has been prepared by destroying diethylaluminum hydride by reaction with diethylzinc. The reaction of hydride-free triethylalumi and titanium tetrachloride in benzene shows the instantaneous reduction of titanium tetrachloride. It has been concluded that the reduction of titanium tetrachloride is not cussed, caused only by the presence of diethylaluminum hydride as an impurity in triethylaluminum, as has been proposed by Roha. Triethylaluminum treated with ethylene at a highi pressure does not reduce titanium tetrachloride under ordinary conditions, even though it contains appreciable amount of the hydride.
On the basis of the above facts, the reaction of Ziegler-catalyst component has been discussed.
Some Acetylene Complexes of Vanadium
Authors: Tsumura Ryuichiro , Hagihara Nobue 
Published: July 2006

Abstract
Some acetylene complexes of vanadium of the π-C5H5(RC2H)V(CO)2 (R=H, n-C3H7, n-C4H9 and (CH3)3C) and π-C5H5(PhC2Ph)V-(PPh3)(CO) types have been prepared by the photochemical reaction of the corresponding acetylene with π-cyclopentadienyl-vanadium tetracarbonyl and its phosphine derivative irespectively. It has been proposed, on the basis of their infrared and nuclear magnetic resonance spectra, that the acetylene complexes of vanadium have a structure in which the acetylene molecule is bonded via two σ-bondings to a vanadium atom.
The Preparation and Polymerization of Divinyl Carbonate
Authors: Murahashi Shunsuke , Nozakura Shun’ichi , Fuji Saburo , Kikukawa Kiyoshi 
Published: July 2006

Abstract
The preparation of divinyl carbonate has been described. The cyclopolymerization of the monomer has been studied under various reaction conditions, and it has been found that cyclopolymerization is not a predominant mode of propagation, for it leaves not less than half a mole of unsafuration per unit structure. The polymer structure has been analyzed by the infrared method and found to contain the 5-membered cyclic carbonate unit, the 6-membered cyclic carbonate unit and the pendant unsaturated carbonate unit.
The polymerization temperature has been shown to have a significant effect on the 5-membered cyclic unit content, increasing the temperature resulting in an increase in the 5-membered unit. The activation energy difference between the intramolecular 5-membered cyclization and the intermolecular propagation has been estimated to be 6.21±0.29 kcal./mol. in the polymerization in a 50% benzene solution and 8.44±0.48 kcal./mol. in bulk polymerization.
A Geochemical Study of Selenium in Volcanic Exhalation and Sulfur Deposits. III. On the Relation between Selenium and Certain Other Constituents, and on the Behavior of Volcanic Gases
Authors: Suzuoki Tetsuro 
Published: July 2006

Abstract
Continuous observations of fumarolic gases have been made in order to study the chemical nature of volcanic gases. A very wide variation in the content of some gaseous constituents has been observed in continuous observation over several hours, and over four years.
Judging from the field observation and the mode of the content variation of several components with the time and the temperature, it is likely that process of the alteration of volcanic gases occurring in the sub-surface plays an important role in producing the difference in the chemical nature of fumarolic gases among the fumarole areas. In addition, the year-to-year variation of the contents of some constituents might provide an indication of the stage of some processes, such as distillation and occlusion, which have occurred in the sub-surface.
It has been found that components like selenium are useful in an examination of the behavior of volcanic gases at an old solfataric volcano like Nasudake, because it is expected that most of the constituents except for selenium have been accumulated in the sub-surface by the past effusion processes and that the accumulated constituents have been occluded in the primary volcanic gases with the change in volcanic activity.
The Reactions of Benzoyl Cyanide with Trivalent Phosphorus Compounds
Authors: Mukaiyaka Teruaki , Kuwajima Isao , Ohno Kiyotaka 
Published: July 2006

Abstract
The reactions of various p-substituted benzoyl cyanides with trivalent phosphorus compounds have been studied. They react with triethyl phosphite to form 2 : 1 adducts which, upon being heated in xylene, decomposed into the corresponding dicyanostilbene oxide and triethyl phosphate. The reaction with tri-n-butylphosphine, on the other hand, gives cis-dicyanostilbene derivatives. These reactions can be explained by a mechanism through similar intermediates.
The Relative Reactivities of Different C–H Bonds in the Photochemical Sulfoxidation of n-Hexane
Authors: Ogata Yoshiro , Izawa Yasuji , Tsuda Takao 
Published: July 2006

Abstract
The product mixture of isomeric hexanesulfonic acids in the ultraviolet light-induced sulfoxidation of n-hexane under various conditions has been analyzed by gas chromatography. On the basis of the data thus obtained, the relative reactivities of different C–H bonds in n-hexane towards light-excited sulfur dioxide and sulfur trioxide have been estimated. The ratio of the reactivities of C1–H : C2–H : C3–H has been calculated to be 1:0.8–1.3: 3.2–6.2. The higher reaction temperatures tend to lower the reactivity of C2–H. The mole ratio of SO2 vs. O2 has an appreciable effect on the composition of the isomers. The lower reactivity of C2–H than that of C3–H may be explained by the intermediary formation of a six-membered ring.
Studies on Mixture Dyeing. III. The Absorption Spectra of Direct Dye Mixtures in an Aqueous Solution
Authors: Morita Zenzo , Sekido Minoru 
Published: July 2006

Abstract
The absorption spectra of a binary mixture of five representative direct dyes in solution have been investigated. The equilibrium constants for complex formation are in the 107–104 range and are in the order: Chrysophenine G - Sky Blue 6B&gt;Benzopurpurine 4B - Sky Blue 6B&gt;Sirius Red 4B - Sirius Supra Blue BRR&gt;Sirius Red 4B - Sky Blue 6B= Benzopurpurine 4B - Sirius Supra Blue BRR&gt;Chrysophenine G - Sirius Supra Blue BRR. The combination of Chrysophenine G and Sky Blue 6B is a typical one in direct dyes. The equilibrium constant for an aggregation of like dye molecules is very much smaller than the value of 104 at room temperature.
Kinetic Studies of the Solution Polymerization of Trioxane Catalyzed by BF3·O(C2H5)2. I. The Effect of the Catalyst and the Water Concentration on the Rate of Polymerization
Authors: Higashimura Toshinobu , Miki Tetsuro , Okamura Seizo 
Published: July 2006

Abstract
In the solution polymerization of TO catalyzed by BF3·O(C2H5)2, water acted as a co-catalyst in n-hexane, a non-polar solvent; in ethylene dichloride, a polar solvent, water slightly accelerated the rate of polymerization, and in nitrobenzene, a more polar solvent, water did not affect the rate at all. The kinetic order of the catalyst concentration to the polymerization rate was 1.0 in benzene, 0.5 in ethylene dichloride, and zero in nitrobenzene. The induction period was very short when water was excluded as much as possible, but it increased with an increase in the water concentration and with a decrease in the catalyst concentration.
On the basis of these results, it may be concluded that the polymerization of TO by BF3·O(C2H5)2 is initiated by the attack of the proton or the ethyl cation on the monomer.
Investigations on Some Amine Complexes of Cobalt(II) Phthalimide. II. Infrared Spectroscopic Measurements
Authors: Narain Gopal 
Published: July 2006

Abstract
Infrared measurements of a series of complexes prepared with cobalt(II) phthalimide and some amines of the [Co(Phthalimide)2(amine)2or1] type have been made. The spectra confirm that both phthalimide ions and amine molecules are co-ordinated; they further suggest that the coordination of phthalimide is through the nitrogen.
Phosphorylation by Means of Ethyl Phosphorodimorpholidite and α-Bromoamides
Authors: Mitsunobu Oyo , Obata Teisuke , Sugaya Yoshiharu , Mukaiyama Teruaki 
Published: July 2006

Abstract
The phosphorylation of alcohols or phenols by means of ethyl phosphorodimorpholidite and either monobromocyanoacetamide or monobromomalonamide has been studied. Further, adenosine 5′-phosphate has been prepared by the reaction of ethyl phosphorodimorpholidite and monobromocyanoacetamide with 2′,3′-isopropylidene adenosine.
The Kinetics of the Acid-Catalyzed Formation of Peracetic Acid from Acetic Acid and Hydrogen Peroxide
Authors: Sawaki Yasuhiko , Ogata Yoshiro 
Published: July 2006

Abstract
The sulfuric acid-catalyzed reversible formation of peracetic acid from acetic acid and hydrogen peroxide in aqueous acetic acid has been studied kinetically. The rate of peracid formation is proportional to the product of the concentrations of acetic acid and of hydrogen peroxide, increasing with an increase in the concentration of sulfuric acid. The plot of the logarithm of the rate constant vs. −H0 gives a straight line, with a slope of 0.82 and 1.10. The mechanism has been discussed in connection with the analogous acid-catalyzed esterification. The equilibrium constants for the present reaction also increase with an increase in the acidity, and the similar plot of logK1 vs. −H gives a straight line with a slope of 0.22. These facts are explicable by considering the protonation of water.
A Study of the Charge-Transfer Complexes. II. The Complexes of Pyromellitic Dianhydride with Polycyclic Aromatic Compounds
Authors: Matsuo Taku 
Published: July 2006

Abstract
The frequency of the charge-transfer absorption of the PMDA complex has been found to be linearly dependent on the energy level of the highest-occupied MO of the aromatic donor as estimated by the Hiickel MO method. The behavior of the complex in the solid state is almost parallel to that in a solution. On the basis of these linear relationships, it has been suggested that PMDA in ethyl acetate behaves as if it is an electron acceptor weaker than that in a solid complex and chloranil in carbon tetrachloride by about 0.2 eV. and 0.53 eV. respectively in the zero order approximation.
Another suggestion has been made that trans-stilbene may be slightly twisted around its essential single bond in a solution but not in the solid complex.
The Optical Properties of Colored Colloidal Systems. III. A Theory of Spherical Particles, with Especial Attention to Systems Dispersed in Colored Media
Authors: Nakagaki Masayuki 
Published: July 2006

Abstract
In the expression of the complex refractive index of a colored colloidal system (m=m0–ik0), the value of m0 may be smaller than unity and k0 may be negative if the medium is colored. Including these cases, the values of x (corresponding to the optical density), y (scattering) and z (absorption) have been calculated for relatively small α and k0 values. The values of the apparent relative refractive index, m′, have been calculated also. These results have been discussed in detail in order to show the effect of the scattering and absorption on the scattering, absorption and apparent refractive index. It has been concluded that the data of a system in which colorless particles are dispersed in a colored medium will be practically equal to those in a colorless medium if the extinction of light according to the Lambert law is corrected properly.
The Synthesis of N-Terminal Acetylpeptides of Ovalbumin and Mammalian Heart Cytochrome c
Authors: Baba Yoshihiko , Sakiyama Fumio , Titani Koiti , Narita Kozo 
Published: July 2006

Abstract
In previous studies acetylglycylserine and acetylglycylaspartylalylglutamic acid had been isolated from the enzymatic digests of ovalbumin and cytochromes c of bovine and equine hearts respectively. Here, in order to confirm the structures of the acetylpeptides isolated, acetylglycyl-l-serine and acetylglycyl-l-aspartyl-l-valyl-l-glutamic acid have been synthesized. It has been proved that the natural acetylpeptides are identical with the synthetic ones in every respect examined. Some troubles encountered during the synthesis of the acetyltetrapeptide have been discussed.
Studies of Cycloheximide-Related Compounds. II. The Acid-catalyzed Condensation of Glutarimide-β-acetaldehyde with Ketones
Authors: Egawa Yoshiyuki , Umezawa Sumio 
Published: July 2006

Abstract
1) Glutarimide-β-acetaldehyde has been condensed with several aliphatic ketones by acidcatalysts to give mainly α,β-unsaturated ketoderivatives. The condensation with methyl iso-propyl ketone has given δ-(1, 1-dimethyl-2-oxo-n-propyl)-β-carbamoylmethyl-δ-valerolactone (III-1) and 3-(2-hydroxy-3,3-dimethyl-4-oxo-n-pentyl)-glutarimide (III-2). It has been found that the latter is an isomer of the product prepared by Nielsen’s aldol condensation procedure.
2) An analogous condensation with Dl-2,4-dimethylcyclohexanone has given Dl-anhydrocycloheximide and two stereoisomers of Dl-gem-cycloheximide. The condensation with (2r:4r)-2, 4-dimethylcyclohexanone has given a similar result.
3) It has been shown that the acid-catalyzed hydration of anhydrocycloheximide affords α-epi-isocycloheximide.
The Selective Halogenation of Methylhydropolysiloxanes : Syntheses of Methylhalopolysiloxanes and Their Derivatives
Authors: Sakiyama Minoru , Nishizawa Yukinori , Okawara Rokuro 
Published: July 2006

Abstract
Bromine was utilized in the presence of stoichiometric amount of pyridine to brominate silanic hydrogen of methylhydropolysiloxanes. Methylbromopolysiloxanes thus obtained and methylchloropolysiloxanes prepared from photo-chlorination of methylhydropolysiloxanes were hydrolyzed with or without methylchlorosilanes to yield new methylhydroxypolysiloxanes and branched methylpoly siloxanes. Preparation of methylhydrocyclopentasiloxanes was also reported.
The Radiation-induced Addition of Hydrogen Sulfide to Olefins
Authors: Sugimoto Ken’ichi , Ando Wataru , Oae Shigeru 
Published: July 2006

Abstract
The radiation-induced free radical addition of hydrogen sulflde to olefins to give the corresponding thiols has been studied. The addition of the thiols to olefins has been found to undergo a free radical chain reaction, readily yielding the corresponding sulfides in the succeeding step. However, the thiols were found to be the only component when an excess of hydrogen sulfide was used. The reactivity of the radical chain reaction decreases with an increase in the carbon number of α-olefins.
The Radiation-induced Isomerization of 2-Butenes
Authors: Ando Wataru , Sugimoto Ken’ichi , Oae Shigeru 
Published: July 2006

Abstract
A detailed study of the radiation-induced trans-cis isomerization of 2-butenes has been made. The effects of halogenated compounds upon 2-butene can be explained by the attack of the halogen radicals formed in irradiation, and a radical chain process can be suggested for the isomerization.
The addition of hexane or cyclohexane to 2-butene in the gas phase has shown a rapid isomerization of trans to cis; it has been suggested that this is caused by the hydrogen atom formed in the irradiation of hexane or cyclohexane. The facile isomerization of 1-butene to trans2-butene by the presence of such hydrocarbons suggests that the hydrogen is readily exchanged with the other hydrogen of olefin, thus leading to the isomerization.
Radiation-induced isomerizations brought by benzene, sulfur dioxide, nitric oxide, carbon disulfide and other molecules have also been examined. The effect of benzene on the trans-cis isomerization of 2-butene has been explained by production of vibrationally-excited triplet states. Results with sulfur dioxide have shown that radiation-induced isomerization is due not only to the formation of the first triplet state, but also to the addition to the double bond, followed by dissociation.
The Rotatory Dispersion and Stereochemistry of Organic Compounds. VIII. Mono- and Dinitrates of Glucopyranose (Preliminary Report)
Authors: Tsuzuki Yojiro , Tanabe Koko , Okamoto Kikuhiko 
Published: July 2006

Abstract
The RD and ultraviolet absorption have been observed with some derivatives of glucose carrying a nitrate group in the C2 and C3positions in order to study the optical contributions of the C2- and C3-ligands with respect to their configurations.
Solid State Polymerization of Binary Component System
Authors: Miura Masatoshi , Hirai Takako , Kawamatsu Shunji 
Published: July 2006

Abstract
The γ-ray irradiation of a solid solution of 3-chloromethyl-3-ethyloxetane and 3,3-bis-(chloromethyl)oxetane has given a copolymer with the same composition as that of the initial monomer mixture, while a BF3-catalyzed copolymerization has formed a copolymer with a different composition from that of the initial monomer mixture. In the polymerization, the solid solution has behaved like each single component crystal in respect to the relation of polymer yield to the irradiation temperature and to the crystal state of the monomers. The copolymer obtained from small crystals grown by rapid cooling has been found to have a narrower distribution of composition than that obtained from large crystals. With a solid solution of 3-chloromethyl-3-ethyloxetane and 3-fluoromethyl-3-ethyloxetance, the polymerization has been studied and similar results obtained.
The mixed crystal of 3-chloromethyl-3-ethyl oxetane and diketene gives a polymer blend. The curve of the polymer yield versus the irradiation temperature is a superposition of those in the each component crystal. The mixed crystal of 3-chloromethyl-3-ethyloxetane and trioxane gives only a homopolymer of oxetane, and the temperature dependence of the yield is similar to that of oxetane, even in an eutectic composition.
Catalytic Asymmetric Benzaldehyde Cyanohydrin Synthesis with Synthetic Optically Active Polymer. II. Cross-linked Poly-(s)-isobutylethylenimine
Authors: Tsuboyama Sei 
Published: July 2006

Abstract
Asymmetric benzaldehyde cyanohydrin synthesis with TDI cross-linked poly-(s)-isobutylethylenimine has been studied. The cyanohydrin obtained was (+)-isomer; its sign is opposite to what it is in the case of the linear polymer. With the linear and soluble polymer which contains some –NH–CO–N= groups, the (+)-isomer was also found to be produced. These results suggest that (1) the reversal of the sign is independent of the reaction phase, and (2) the configuration of the product is not always controlled by the configuration of the asymmetric carbon in the catalyst but by the conformation of the catalytic center.