bluuebunny/crossref_metadata_2025 huggingface dataset:
Photocatalytic Oxidation of Alcohols on TiO2
Authors: Yamagata Sadamu , Nakabayashi Seiichiro , Sancier Kenneth M , Fujishima Akira
Published: July 2006

The reaction mechanisms of the photocatalytic oxidation of several different alcohols on TiO2 were investigated by three experimental techniques: spin trapping, photocurrent measurement, and product analysis. The results are interpreted according to the band model of a semiconductor and current doubling. It was found that alcohols with α-hydrogens gave low concentrations of spin adducts since their photoproduced radicals have short lifetimes on TiO2 due to a current-doubling process. Also, it was found that oxygen participated in a radical chain mechanism in the photocatalytic oxidation of ethanol to acetaldehyde.
Thermotropic Liquid Crystal Properties of Alkylammonium Alkanesulfonates
Authors: Matsunaga Yoshio , Nishida Kiyoshi
Published: July 2006

Alkylammonium methane-, ethane-, 1-propane-, and 1-butanesulfonates exhibit a smectic A phase when the cation carries a dodecyl or longer alkyl group. The temperature range of the existence decreases in the following order: methanesulfonates>1-propanesulfonates>ethanesulfonates>1-butanesulfonates. In the last series, the mesophase is entirely metastable. The layer spacing in the 1-propanesulfonate is shorter by about 0.30 nm than that of the corresponding methanesulfonate, even though the alkyl chain length in the anion is increased by 0.25 nm.
Surface Potential of Mixed Micelles Composed of Prostaglandin B2 and Heptaethylene Glycol Dodecyl Ether by the Fluorescence Method
Authors: Yokoyama Shoko , Kaneko Akiko , Fujie Tadao
Published: July 2006

The surface state of negatively charged mixed micelles prepared by addition of prostaglandin B2 (PGB2) to nonionic heptaethylene glycol dodecyl ether (HED) has been investigated and the surface potential (Δψ) of the micelles has been estimated by measuring the fluorescence intensity of ammonium 8-anilino-1-naphthalenesulfonate (ANS) as a fluorescent probe. Since the binding constant of ANS, k, is dependent on the surface potential of the micelle, the value of Δψ was determined according to the equation Δψ=−59.16log(k0⁄k) at 25°C, where k0 is the k of HED micelle. The value of |−Δψ| increases with increasing mole fraction of PGB2 (XPGB2) and decreases with increasing ionic strength (J). These changes are due to the effects of the negative charge of PGB2 and of ionic atmosphere of Na+, respectively. Surface charge density (σ) was, therefore, determined from Δψ according to the Gouy-Chapman theory, with a result that σ is nearly independent of J and proportional to XPGB2. These results have led to a conclusion that the state of the diffuse layer surrounding the Stern layer on the micelle surface is represented well by the Gouy-Chapman theory as well as a previous result for the system of sodium dodecyl sulfate (SDS) and HED. The value of |−σ| for PGB2 micelle is less than that for SDS micelle, which suggests that PGB2 forms a loosely packed micelle.
Crystal Structures and Electrical Properties of TSeCn-TTF (n=2 and 4)
Authors: Wang Ping , Mori Takehiko , Nakano Chikako , Maruyama Yusei , Inokuchi Hiroo , Iwasawa Naoko , Yamochi Hideki , Urayama Hatsumi , Saito Gunzi
Published: July 2006

An organic compound TSeCn-TTF [tetrakis(alkylseleno) tetrathiafulvalenes] with n=2, crystallizes in the monoclinic space group P21⁄a, a=23.218(5), b=8.960(3), c=10.489(3) Å, β=96.61(2)°, V=2168(1) Å3, and Z=4; the compound with n=4 crystallizes in the triclinic space group P\bar1, a=9.198(1), b=10.539(2), c=8.248(2) Å, α=113.16(2), β=96.02(2), γ=90.61(2)°, V=729.9(3) Å3 and Z=1. The molecule with n=2 has a bent structure, like a boat; and the molecule with n=4 has a structure in which each of the four alkyl chains is stretched towards different directions. The temperature dependence of electrical resistivity and the charge-carrier mobility have been measured, and the resistivities at room temperature are ρa⁄ρb⁄ρc=3.3×109⁄2.0×109⁄6.0×1011 and 2.2×1011⁄1.0×1011⁄1.3×1011 (Ω cm) for TSeC2-TTF and TSeC4-TTF, respectively. The quite isotropic character in the resistivities of a TSeC4-TTF crystal may originate from its rather strange molecular structure.
A New Permanganate–Nitrite–Formic Acid–Methanol Oscillator
Authors: Morita Makoto , Iwamoto Kazutoshi , Sen\={o} Manabu
Published: July 2006

Sustained oscillation and birhythmicity have been observed when aqueous solutions of potassium permanganate, potassium nitrite, formic acid, and methanol were mixed in a continuous-flow stirred tank reactor. A detailed phase diagram is shown. This new oscillator is composed of non-halogen compounds and the first example of the nitrogen-based oscillator.
57Fe-Mössbauer and 13C-CP-MAS NMR Spectroscopic Studies of the Reaction Products of Ferrocene Derivatives with Mercury(II) Salts
Authors: Watanabe Masanobu , Masuda Yuichi , Motoyama Izumi , Sano Hirotoshi
Published: July 2006

The unstable adducts of ferrocene and methylferrocene and the stable adducts of biferrocene, diferrocenylmethane, 1,2-diferrocenylethane, and [n]ferrocenophane (n=2, 3) with HgX2 (X=Cl, Br, I, and BF4) were studied by means of 57Fe-Mössbauer and high-resolution solid-state 13C NMR spectroscopies. The large quadrupole splitting (Q. S.) values in the 57Fe-Mössbauer and the large low-field shifts in the 13C-CP-MAS NMR, spectroscopy suggest the presence of a direct chemical bond between the Fe and Hg atoms.
Seasonal Changes in Eicosapentaenoic and Arachidonic Acid Contents in Bivalves and Plankton Collected from Lake Hamana
Authors: Adachi Kyoko , Ichinose Norio , Shimizu Chiaki , Okamoto Ken
Published: July 2006

Bivalves and plankton samples were collected monthly for one year from brackish Lake Hamana in Japan, and contents of 5,8,11,14,17-eicosapentaenoic acid (EPA) and 5,8,11,14-eicosatetraenoic acid (arachidonic acid, AA) and their weight percentage to total fatty acids were determined by fluorescence high-performance liquid chromatography. The results regarding bivalves showed that the EPA and AA levels are approximately ten times higher in liver than in adductor on the average for one year, and are remarkably dependent upon the season. The seasonal changes of EPA and AA contents in bivalve liver are seemingly related to those of plankton, which are the diet of bivalves. From these facts, it can be seen that plankton is the main origin of EPA and AA in bivalve bodies and supply these fatty acids all the way up to humans through a food chain.
X-Ray Crystal Structures of cis- and trans-Dinitrobis(1,4-butanediamine)cobalt(III) Nitrates. Conformation of Seven-Membered Chelate Rings
Authors: Shimoi Mamoru , Fujinawa Yuki , Ogino Hiroshi , Kanamori Kan , Kawai Kiyoyasu
Published: July 2006

The structures of cis- and trans-dinitrobis(1,4-butanediamine)cobalt(III) nitrates were determined by the single-crystal X-ray diffraction method. cis-[Co(NO2)2(tmd)2]NO3 (tmd=H2N(CH2)4NH2) is monoclinic with the space group P21⁄a; the cell constants are a=23.878(4), b=8.403(1), c=16.675(3) Å, β=103.24(1)°; Z=8, and the final R value was 0.051. trans-[Co(NO2)2(tmd)2]NO3·H2O is triclinic with the space group P\bar1; the cell constants are a=9.753(3), b=13.909(4), c=6.327(1) Å, α=102.07(2), β=91.05(2), γ=87.83(3)°; Z=2, and the final R value was 0.058. Both complexes have a slightly distorted octahedral geometry around the cobalt center. The conformations of the seven-membered chelate rings have twist-chair and chair forms for the cis and trans complexes, respectively.
Preparation and Stereochemistry of Cobalt(III) Complexes Containing 1,1,11,11-Tetraphenyl-4,8-diaza-1,11-diphosphaundecane or (3S,9S)-3,9-Dimethyl-1,1,11,11-tetraphenyl-4,8-diaza-1,11-diphosphaundecane,(C6H5)2PCH2CHRNHCH2CH2CH2NHCHRCH2P(C6H5)2 (R=H or CH3)
Authors: Jung Min-Ho , Atoh Masamichi , Kashiwabara Kazuo , Fujita Junnosuke
Published: July 2006

Two new quadridentate phosphine ligands 1,1,11,11-tetraphenyl-4,8-diaza-1,11-diphosphaundecane (pp-232PNNP) and (3S,9S)-3,9-dimethyl-1,1,11,11-tetraphenyl-4,8-diaza-1,11-diphosphaundecane (SS(C)-pp-232PNNP), and several their cobalt(III) complexes were prepared and characterized. The RS(N) isomers of trans-[CoCl2(pp- or SS(C)-pp-232PNNP)]+ were formed by oxidation of cobalt(II) complexes of these ligands in dichloromethane with chlorine, while the RR,SS(N), and RR(N) isomers of the pp-232PNNP and SS(C)-pp-232PNNP complexes, respectively, were derived from the corresponding carbonato complexes and hydrochloric acid. The [Co(O-O)(pp- or SS(C)-pp-232PNNP)]n+ (O–O= CO32−, C2O42−, C5H7O2−) complexes yielded only a cisβ isomer. The stereochemistry of the complexes was discussed on the basis of the absorption, circular dichroism and NMR spectra.
High Performance Micro-Enzyme Sensor Using Platinized Microelectrode
Authors: Ikariyama Yoshihito , Yamauchi Shigeru , Aizawa Masuo , Yukiashi Tomoaki , Ushioda Hiroo
Published: July 2006

A unique micro-enzyme sensor for the determination of glucose has been prepared by incorporating glucose oxidase into the micropores of a platinized microelectrode. The electrode diameter is in the range from 10 μm to 200 μm. The detection limit is 5×10−7 mol L−1 for glucose, and an excellent linearity is obtained in the concentration range from 5×10−7 to 10−2 mol L−1 in the case of micro-enzyme electrode whose diameter is larger than 50 μm. In the case of micro-enzyme electrode whose diameter is 10 μm, the detection limit for glucose is 10−5 mol L−1, and the linearity is observed in the concentration range from 10−5 to 5×10−2 mol L−1. The sensor responds to every glucose sample of different concentration in 3 s or less, and the coefficients of variation for glucose (1 mM) determination were within 2%. The sensor output was stable over 4 weeks. This unique microfabrication approach to micro-enzyme electrodes enables the immobilization of intact enzyme molecules by a simple procedure.
Photochemical Trifluoromethylation of Some Aromatic and Heteroaromatic Compounds with Trifluoromethyl Bromide
Authors: Akiyama Takeo , Kato Kohji , Kajitani Masatsugu , Sakaguchi Yoshio , Nakamura Junko , Hayashi Hisaharu , Sugimori Akira
Published: July 2006

The photochemical introduction of trifluoromethyl group with CF3Br in aromatic and heteroaromatic rings was investigated for 9 compounds. Naphthalene, anthracene, anisole, N,N-dimethylaniline, ferrocene, benzo[b]thiophene, isoquinoline, and N-methylpyrrole gave trifluoromethylated products in 6.5–100% yields. In one step from uracil, a pharmacologically important 5-trifluoromethyluracil can be synthesized by this method in 11% yield. Based on the mechanistic study carried out for the naphthalene–CF3Br–CH3CN system, the reaction is found to proceed via the electron transfer from an excited singlet state of naphthalene to CF3Br.
Preparation of Mesoverdohemochrome IXα Dimethyl Ester and Mössbauer Spectra of Related Porphyrins
Authors: Saito Setsuo , Sumita Shigeya , Iwai Kumiko , Sano Hirotoshi
Published: July 2006

Mesobiliverdin IXα dimethyl ester (7) was obtained by hydrogenation of protobiliverdin IXα dimethyl ester (8). Zinc 5-oxamesoporphyrin IX dimethyl ester tetrafluoroborate (6) was prepared by the cyclization of 7 with zinc acetate in acetic anhydride followed by a treatment with aqueous sodium tetrafluoroborate. Bis(pyridine) mesoverdohemochrome IXα dimethyl ester (4) was obtained by the cyclization of 7 with both iron(II) sulfate and iron(III) chloride in acetic anhydride containing a small amount of pyridine. Bis(tosylmethyl isocyanide) mesoverdohemochrome IXα dimethyl ester (5) was prepared by the addition of excess tosylmethyl isocyanide (TsCH2NC) to 4. Both 4 and 5 reacted with ammonia to give iron(III) 5-azamesoporphyrin IX dimethyl ester (10). The Mössbauer spectra of bis(pyridine) verdohemochromes (4, 13, and 14) snowed doublet peaks having parameters of δ=0.41–0.43 mm s−1 and ΔEQ=1.24–1.26 mm s−1, indicating that the oxidation states of the central irons of these complexes are iron(II). Bis(TsCH2NC) verdohemochromes (5, 15, and 17) showed single peaks having parameters of δ=0.21–0.28 mm s−1. Unstable intermediate and stable final bis(TsCH2NC) octaethyl verdohemochromes, obtained by the addition of TsCH2NC to 4, were compared with the 1H NMR and Mössbauer spectra.
Crystal and Molecular Structures of Tetraisopropyl 1,1′-(1,8-Naphthylene)bis[1H-1,2,3-triazole-4,5-dicarboxylate] and Diisopropyl 1-(1-Naphthyl)-1H-1,2,3-triazole-4,5-dicarboxylate
Authors: Nagawa Yoshinobu , Goto Midori , Honda Koichi , Nakanishi Hiroshi
Published: July 2006

Molecular structures of the title compounds, which belong to the class of peri-substituted naphthalenes, have been determined by means of X-ray diffraction. Tetraisopropyl 1,1′-(1,8-naphthylene)bis[1H-1,2,3-triazole-4,5-dicarboxylate] (1), monoclinic, space group C2⁄c, a=35.034(3), b=9.717(1), c=18.504(1) Å, β=96.43(1)°, Z=8; Diisopropyl 1-(1-naphthyl)-1H-1,2,3-triazole-4,5-dicarboxylate (2), monoclinic, space group P21⁄n, a=16.246(2), b=10.115(1), c=12.390(1) Å, β=96.67(1)°, Z=4. The dihedral angles between the mean plane of the naphthalene ring and that of the triazole ring are 88° and 85° for 1 and 2, respectively. The naphthalene framework of 1 is much more distorted than that of 2 because of a steric repulsion between the two triazole rings with bulky ester groups of 1.
Arylation of Olefins by Arylazo Aryl Sulfones under Palladium(0) Catalysis
Authors: Kamigata Nobumasa , Satoh Akira , Kondoh Tetsuya , Kameyama Masayuki
Published: July 2006

The palladium(0)-catalyzed reaction of arylazo aryl sulfones with olefins in benzene at 80°C gave aryl-substituted olefins in good yield. Diarylpalladium(II) species was proposed as an intermediate in this reaction.
The Photocatalytic Activity of a Platinized Titanium Dioxide Catalyst Supported over Silica
Authors: Domen Kazunari , Sakata Yoshihisa , Kudo Akihiko , Maruya Ken-ichi , Onishi Takaharu
Published: July 2006

The effect of the amount of TiO2 loading on the photocatalytic activity of H2 evolution from aqueous methanol solution over a platinized TiO2/SiO2 catalyst was studied. UV diffuse reflectance spectra of TiO2/SiO2 showed the blue shift of absorption edge for the catalyst of lower amount of TiO2 loading, which suggested the higher dispersion of TiO2 on SiO2. The activity decreased monotonously with the decrease of the amount of TiO2 loading over SiO2, i.e. with the increase of the dispersion.
Chromium(VI) or Ruthenium(II) Complex Catalysis in Oxidation of Alcohols to Aldehydes and Ketones by Means of Bis(trimethylsilyl) Peroxide
Authors: Kanemoto Shigekazu , Matsubara Seijiro , Takai Kazuhiko , Oshima Koichiro , Utimoto Kiitiro , Nozaki Hitosi
Published: July 2006

Bis(trimethylsilyl) peroxide (BTSP) serves as an effective oxidant of alcohols in the presence of chromium(VI) or ruthenium(II) complexes as catalysts in dichloromethane. Selective oxidation of primary alcohols in preference to secondary ones using RuCl2(PPh3)3 as a catalyst is also described.
Quenching of Excited Singlet and Triplet States of Some Polyfused Arenes by Dihalobenzenes
Authors: Mallik G K , Pal T K , Ganguly T , Banerjee S B
Published: July 2006

External heavy atom effect on the emission spectra of naphthalene, phenanthrene, and chrysene by perturbers dihalobenzenes are investigated to estimate different nonradiative rate constants associated with the depletion of the singlet and the triplet states of the fluorescers. The bimolecular fluorescence quenching rate constant kq has been evaluated at 300 K by applying Stern–Volmer relation. The dihalobenzene quenchers have triplet states lying below the singlet states of the fluorescers and the overall quenching rate kq is composed of two rate constants, namely, the intramolecular intersystem crossing rate kqISC and the singlet–triplet energy transfer rate constant kqST. The relative magnitudes of the two rate constants kqISC and kqST have been examined in the light of the energy conditions controlling the associated processes. At 77 K, the phosphorescence decay curve of the fluorescers in the presence of dihalobenzenes is biexponential and the triplet decay of the perturbed fraction of the fluorescers is exponential. It is concluded that at the low temperature, heavy atom interaction in the systems studied mainly proceeds through CT mechanism. Speculative suggestion has been made to account for enhancement of phosphorescence emission of polyfused arenes in EtOH solution.
Stereochemistry of the Reactions of Trimethylgermyl Anions with 4-t-Butylcyclohexyl Derivatives
Authors: Mochida Kunio , Kugita Tsuyoshi
Published: July 2006

The stereochemistry of trimethylgermyllithium, -sodium, and -potassium with cis- and trans-4-t-butylcyclohexyl bromides and trimethylstannanes was investigated by 1H NMR spectroscopy. With the 4-t-butylcyclohexyl derivatives trimethylgermyl anions gave mixtures of cis- and trans-4-t-butylcyclohexyltrimethylgermanes. These results confirmed that free-radical pathways are important in such reactions.
Facile Reaction of Te-Aryl Benzenecarbotelluroates, ArCOTeAr′, with Methyl Iodide and Halogens
Authors: Singh Harkesh B , Sudha Narasimhan
Published: July 2006

Reaction of Te-aryl benzenecarbotelluroates of the type ArCOTeAr′ (Ar=phenyl p-tolyl, p-bromophenyl; Ar′=phenyl, p-methoxyphenyl) with methyl iodide was found to give symmetrical telluronium salts, [Ar′Te(CH3)2]+I− in good yields. The reactivity of one of these benzene carbotelluroates towards halogens was also examined.
The Vapor-Phase Preparation of V–P–O Catalysts Effective for Butane Oxidation to Maleic Anhydride
Authors: Takita Yusaku , Hashiguchi Takao , Matsunosako Hitoshi
Published: July 2006

Almost pure α-VOPO4·2H2O powder was obtained by a vapor-phase reaction between POCl3, VOCl3, and water at about 763K in the presence of oxygen. Although α-VOPO4·2H2O changed into α- and β-VOPO4 in the calcination in N2, it was transformed into (VO)2P2O7 and a small amount of β-VOPO4 by in situ activation at 733 K at the heating rate of 10 K min−1 in a C4H10–O2–N2 stream, the resulting catalysts effected the selective oxidation of butane to maleic anhydride comparable to pure (VO)2P2O7.
Oxidation of Benzylic and Allylic Alcohols with Cobalt(III) Acetate in Acetic Acid in the Presence and Absence of Sodium Bromide
Authors: Hirano Masao , Morimoto Takashi , Itoh Keiko
Published: July 2006

Benzyl alcohol and its o-, m-, and p-substituted derivatives afforded fairly good yields of the corresponding benzaldehydes through a reaction with a Co(III)–NaBr system. With allylic alcohols, this system failed in a selective formation of unsaturated carbonyl compounds. In the latter cases, the products were effectively obtained by using a higher concentration of cobalt(III) acetate in the absence of NaBr.
Emission Spectrum of Acetylene by Controlled Electron Impact
Authors: Yoshidome Toshifumi , Taniguchi Masaharu , Nakashima Keiji , Kawazumi Hirofumi , Ogawa Teiichiro
Published: July 2006

Emission spectra of C2H2 and C2D2 excited by collisions with electrons of 7–20 eV show a broad and diffuse band in the 240–400 nm region and this band was assigned to the S1(lower vibrational levels)–S0 transition of acetylene on the basis of its .wavelength, excitation function (threshold: 5.5 eV) and lifetime (323±30 ns). Their emission cross sections are on the order of 10−19 cm2. Among intense fragment emissions at higher electron energies, band of C2H has also been observed and its lifetime is 3.9±0.8 μs.
Addition of N-(Hydroxymethyl)phthalimide to Methacrylates by Carbon–Carbon Bond Formation
Authors: Kurita Keisuke , Itoh Hiroshi , Chikamori Shunji , Mabuchi Tomoyuki
Published: July 2006

N-(Hydroxymethyl)phthalimide undergoes addition to the carbon–carbon bond of methacrylates effectively in sulfuric acid, resulting in the formation of a new carbon–carbon bond.
The Synthesis of Se-Alkyl Alkaneselenoates via (1-Iodo-1-alkenyl)dialkylboranes
Authors: Hoshi Masayuki , Masuda Yuzuru , Arase Akira
Published: July 2006

Se-Alkyl alkaneselenoates were formed in moderate to good yields by successive reactions of (1-iodo-1-alkenyl)bis(1,2-dimethylpropyl)boranes with alkylselenomagnesium bromides and alkaline hydrogen peroxide.
Synthesis and Chemiluminescence of 5-[(2-Pyridyl)-, (2-Pyrazinyl)-, and (Substituted 2-pyrazinyl)amino]-1,2,4-trioxanes
Authors: Nakamura Hideshi , Goto Toshio
Published: July 2006

From pyridyl- and pyradinylamines and isobutylaldehyde were prepared the corresponding 5-arylamino-1,2,4-trioxanes, whose chemiluminescence was studied by comparing with those of Cypridina luciferin analogs.
Catalytic Upgrading of SRC from Pyrolytic Coal Liquefaction and Hydrocracking of Polycyclic Aromatic Hydrocarbons
Authors: Song Chunshan , Hanaoka Kouji , Ono Tomohiro , Nomura Masakatsu
Published: July 2006

Catalytic upgrading of SRC (solvent refined coal) derived from short contact time pyrolytic liquefaction of Wandoan subbituminous coal was carried out. The upgrading with unsulfided and sulfided nickel–molybdenum catalysts produced about 77 wt% and 85 wt% of oil plus light distillates from the SRC, respectively. The reactions occurring during the upgrading process were assessed by referring to the hydrocraking of related polycyclic aromatic hydrocarbons.
Classification of DNA Sequences by Hayashi’s Quantification (III) Method. Sequences Involving 5′-Splice Signals in Pre-mRNA of Higher Eukaryotes’ Genes
Authors: Iida Yôichi
Published: July 2006

Concerning the signals which direct the excision of introns from mRNA precursors in higher eukaryotes’ genes, a consensus sequence, \oversetCAAG/GT\oversetAGAGT, has been proposed with a 5′-splice site, but actual 5′-splice site sequences differ from it to a greater or lesser degree. In the present paper, we took a set of 1751 sequences, which are composed of 9-nucleotide sequences including 5′-splice signals and of other sequences including no such signals. Hayashi’s quantification analysis (Class III) was applied to such a system. Assuming no external criterion for 5′-splice signals, we examined how the 1751 sequences show responses to the positions and species of nucleotides. The optimum classification led to a fair separation of the 5′-splice signal sequences from sequences including no such signals. The results were compared with those derived previously by the use of the quantification (Class II) method.
Environmental Intensity Increments of the S1(nπ*)←S0 Absorption Spectra of Benzil in Fluid Solutions
Authors: Miyata Kaori , Koyanagi Motohiko
Published: July 2006

A remarkable solvent effect on intensity of molecular electronic transitions has been found in near UV absorption spectra of benzil. Great intensity enhancement is observed in alcohols and in chloromethanes as well as in nitriles. Parameters which are required to explain the origin of those environmental intensity enhancement are neither solvent refractive indexes nor polarities. A some rotationally flexible freedom around the –OC–CO– axis of benzil in the solvent seems important. Week complex formation between the solute and the solvent molecule is likely to play an important role. Similar solvent effects are found for absorption spectra of benzophenone and dicyclohexyl ketone, but with more complexity regarding their spectral shifts in contrast to the case of benzil.
Vibrational Analysis of Tangled Spectra. II. Role of Phonon Side Band Structure in the T←S Spectra of Acetophenones
Authors: Nakashima Kenichi , Futami Hiroshi , Koyanagi Motohiko
Published: July 2006

T1,2←S0 phosphorescence excitation spectra of acetophenone, acetophenone-methyl-d3, and acetophenone-phenyl-d5 have been observed in the crystals at 4.2 K. Vibration analysis for the observed tangled spectra becomes possible only by the help of calculations which allow untangling of the tangled spectra. The calculations involve interstate mixings, by vibronic and environmental interactions, among 36 crude adiabatic Born-Oppenheimer vibronic functions of 3ππ* and 3nπ* states. A new aspect of the present work is introduction of a role of intermolecular phonon side bands into the calculations; this clearly showing that the observed spectra are reproduced much better than unless otherwise.
Study of the Effect of Structural Factors on Magnetism of Di-μ-alkoxodicopper(II) Complexes by Ab Initio MO Calculations
Authors: Handa Makoto , Koga Nobuaki , Kida Sigeo
Published: July 2006

The effect of variation of structural factors on the spin-exchange interaction between copper(II) centers in dialkoxo-bridged dinuclear copper complexes were studied by the ab initio MO method with UHF formalism. The calculations were performed on di-μ-methoxotetraamminedicopper(II). The J-values were obtained as functions of Cu–O–Cu angle, dihedral angle between two coordination planes, planarity of bonds on the bridging oxygens, tetrahedral distortion of coordination planes, and the tilt of O–C bond from the O–O axis. The results demonstrated that the Cu–O–Cu angle most effectively affect the J-value but the other factors are less effective.
Oxygen-17 NMR Study of the Uranyl Ion. V. Kinetics and Mechanisms of Formation and Decomposition Reactions of Di-μ-hydroxo-bis[uranyl(VI)] Ion in Aqueous Nitrate Solutions
Authors: Jung Woo-Sik , Harada Masayuki , Tomiyasu Hiroshi , Fukutomi Hiroshi
Published: July 2006

The rates of formation and decomposition reactions of di-μ-hydroxo-bis[uranyl(VI)] ion, (UO2)2(OH)22+, have been measured in aqueous nitrate solutions (ionic strength=0.5 M; M= mol dm−3) by 17O NMR spectroscopy. In weakly acidic solutions the reactions obey the rate law:

d[(UO2)2(OH)22+]⁄dt=k2[UO22+][UO2OH+]−k−2Ka[H+][(UO2)2(OH)22+]⁄2,

where Ka=[(UO2)2OH3+]/[H+][(UO2)2(OH)22+]. A mechanism involving a single-bridged binuclear intermediate, (UO2)2OH3+, is proposed. Rate constants (M−1 s−1) at 25 °C and activation parameters ΔH\eweq (kJ mol−1) and ΔS\eweq (J K−1 mol−1) for the formation and decomposition are as follows: 1.52×105, 18.9±1.5, and −82.4±5.0 for k2 and 2.10×105, 23.6±1.3, and −64.0±4.2 for k−2Ka. The rate of the decomposition reaction is compared with that in several related systems.
Role of the Interface in Solvent Extraction Processes
Authors: Freiser Henry
Published: July 2006

This paper reviews 25 years’ investigation of kinetics of metal chelate extraction systems under high speed stirring conditions. Values of chelate formation rate constants for both analytical and hydrometallurgical extractants derived from such measurements using the assumption that the rate-determining step(s) occur in bulk aqueous phase, have been shown to be in reasonable agreement with expectations. Nevertheless, the introduction of the microporous Teflon phase separator in extraction kinetics resulted in clear evidence of reaction pathways involving the interface, as well as the bulk aqueous phase, even for simple chelating extractants.
A Convenient Synthesis of 1α-Hydroxyvitamin D2
Authors: Tachibana Yoji
Published: July 2006

The enol acetylation of ergosta-1,4,6,22-tetraen-3-one (4) by treatment with isopropenyl acetate under acidic condition gave 3-acetoxy-1,3,5,7,22-ergostapentaene (5). The reduction of 5 with calcium borohydride afforded ergosta-1,5,7,22-tetraen-3β-ol (6). The t-butyldimethylsilyl ether derivatives (8) of the Diels–Alder cyclo adduct (7) derived from 6 and 4-phenyl-3H-1,2,4-triazole-3,5-dione was oxidized with m-CPBA to the diepoxide adduct (9). The 1α,2α-epoxide of the diepoxy alcohol (10) obtained after the removal of the silyl group of 9 was selectively reduced with LiAlH4 to yield the 22,23-epoxy-1α,3β-diol (11) and 11 was subsequently converted to the corresponding diacetate (12). The deoxygenation of the 22,23-epoxide of 12 with a combination of sodium iodide and trifluoroacetic anhydride gave the 1α-acetoxyergosteryl acetate (13). Irradiation of 13 with a high-pressure mercury lamp followed by thermal isomerization, saponification, purification on silica gel and crystallization gave 1α-hydroxyvitamin D2 (1) as colorless crystals.
Synthesis of Gramicidin S Analogues Consisting of Fourteen Amino Acid Residues
Authors: Tamaki Makoto , Takimoto Michiaki , Muramatsu Ichiro
Published: July 2006

Four cyclotetradecapeptides related to gramicidin S, cyclo(–Val–Orn–Leu–Leu–d-Phe–Pro–Leu–)2 (14-peptide-1), cyclo(–Val–Orn–Leu–d-Leu–d-Phe–Pro–Leu–)2 (14-peptide-2), cyclo(–Val–Orn–Leu–Leu–d-Phe–Pro–d-Leu–)2 (14-peptide-3), cyclo(–Val–Orn–Leu–d-Leu–d-Phe–Pro–d-Leu–)2 (14-peptide-4), were prepared in order to investigate the contribution of the ring size and the amino acid sequences around the Pro residue to the antibiotic activity and conformation. The CD spectra of these synthetic peptides in ethanol solutions were different from each other, indicating that they possess various conformations in ethanol solutions. 14-Peptides-1, -2, and -3 showed 1/4–1/8 of the antibiotic activity of gramicidin S against the gram-positive microorganisms tested, whereas 14-peptide-4 showed no activity. A clear relationship between CD spectra and the antibiotic activity of these synthetic peptides could not be found.
The Crystal and Molecular Structure of Scandium(III), Yttrium(III), and Some Lanthanoid(III) p-Toluenesulfonates, [Sc(C7H7SO3)2(H2O)4](C7H7SO3)·2H2O and [M(C7H7SO3)2(H2O)6](C7H7SO3)·3H2O (M=Y, Sm, Gd, Dy, Ho, Er, Yb); and Yttrium(III) and Dysprosium(III) 2-Naphthalenesulfonates, [M(C10H7SO3)2(H2O)6](C10H7SO3)·3H2O (M=Y, Dy)
Authors: Ohki Yoshiyuki , Suzuki Yasuo , Takeuchi Toshio , Ouchi Akira
Published: July 2006

Scandium(III) p-toluenesulfonate hexahydrate, as well as the isomorphous yttrium(III) and six lanthanoid(III) (Sm, Gd, Dy, Ho, Er, and Yb) p-toluenesulfonate enneahydrates, were synthesized and their structures were determined by the single-crystal X-ray diffraction technique. The scandium salt was monoclinic with the space group P21⁄a, Z=4 (the cell constants were a=23.672(16), b=15.792(6), c=7.7543(12) Å, β=92.86(3)°, and the final R value was 0.059). The central metal atom is hexa-coordinated, being in an octahedral geometry, in which two unidentate sulfonate oxygen atoms (in cis-configuration) and four water oxygen atoms are ligated. The latter seven salts were also monoclinic with a space group of P21⁄n, and Z=4 (the cell constants of the holmium salt, for example, were a=25.058(19), b=7.476(2), c=17.802(10) Å, β=98.80(8)°, and its final R value was 0.039). The central metal atom of these complexes are octa-coordinated, being in a square-antiprism geometry in which two unidentate sulfonate and six water oxygen atoms are ligated. In both types of complexes, no ligand bridgings were found, and one in three sulfonate ions was not coordinated to the metal atom. In the respective lanthanoid(III) complexes, M–O(sulfonato) bonds are shorter than the M–O(water) ones. The corresponding M–O bonds of the respective complexes decrease, almost proportional to the sum of the Shannon’s ionic radii of the metal and oxygen, with the metal atomic numbers. Each M–O bond length of the yttrium(III) p-toluenesulfonate and 2-naphthalenesulfonate had the value expected from the corresponding bond lengths of the series of the respective isomorphous lanthanoid(III) salts, referring to its metal ionic radius.
Synthesis of Branched-Chain Oligosaccharides in Sarsasaponins by Dehydrative Glycosylation
Authors: Koto Shinkiti , Morishima Naohiko , Uchino Masaharu , Fukuda Misa , Yamazaki Masayo , Zen Shonosuke
Published: July 2006

The branched-chain oligosaccharides, 6-O-(β-d-glucopyranosyl)-4-O-(α-l-rhamnopyranosyl)-d-glucopyranose, and 2,6-di-O-β-d-glucopyranosyl)-4-O-(α-l-rhamnopyranosyl)-d-glucopyranose, which compose sarsasaponins, as well as the structurally related 2-O-(β-d-glucopyranosyl)-4-O-(α-l-rhamnopyranosyl)-d-glucopyranose were synthesized stepwise via dehydrative glycosylation by a ternary mixture of p-nitrobenzenesulfonyl chloride, silver triflate, and triethylamine.
A Michael Addition and Peterson Olefination Sequence Using 1-Silylethenyl Sulfides and Sulfoxide
Authors: Kanemasa Shuji , Kobayashi Hiroshi , Tanaka Junji , Tsuge Otohiko
Published: July 2006

Reaction of organolithiums with a 1-(trimethylsilyl)ethenyl sulfide produces 1,2-bis(trimethylsilyl)cyclopropanes, while use of 1-silylethenyl sulfides bearing a bulkier silyl moiety results in exclusive formation of the corresponding Michael adduct anions which are then quenched with aldehydes to give vinyl sulfides. On the contrary, a 1-(trimethylsilyl)ethenyl sulfoxide undergoes smooth Michael addition with a variety of organo-metallics and the resulting carbanion intermediates can be quenched with aldehydes to produce vinyl sulfoxides. Scope and limitations of these sequential reactions are discussed.
Generation of Sulfur-Functionalized Nitrile Oxide, (Phenylthio)acetonitrile Oxide, and Synthetic Applications
Authors: Kanemasa Shuji , Norisue Yasumasa , Suga Hiroyuki , Tsuge Otohiko
Published: July 2006

The first generation of a new sulfur-functionalized nitrile oxide 1,3-dipole, (phenylthio)acetonitrile oxide, is presented. Its cycloadditions to a variety of olefins and acetylenes lead to 3-(phenylthiomethyl)-2-isoxazolines and -oxazoles, the formers being selectively deprotonated at the carbon substituted by the sulfur moiety. The resulting sulfur-stabilized carbanions react with aldehydes, esteric Michael acceptors, and alkyl halides to enable the introduction of a carbon substituent to the side chain on 3-position. Raney Ni reduction of these 2-isoxazolines gives β,β′-dihydroxy ketones and β-hydroxy ketones.
Interaction of Poly[N-(3-aminopropyl)glycine] and Its Derivatives with Lipid Membrane
Authors: Yagi Yoshiko , Kimura Shunsaku , Imanishi Yukio
Published: July 2006

Poly[N-(3-aminopropyl)glycine] (PolyNAPGly, 5) and its derivatives were synthesized as model peptides of the membrane-bound enzymes, and investigated on their interactions with lipid membrane. PolyNAPGly (5) was shown to be distributed to dipalmitoylphosphatidyl choline bilayer membrane without destruction of the vesicle structure. Dodecyl groups were introduced to the side chains of PolyNAPGly (5), and found to facilitate binding of the polymer to lipid membrane. However, the introduction of the excess amount of hydrophobic groups to PolyNAPGly (5) caused the formation of polymer micelles, and the addition of such polymers to lipid vesicles destroyed the membrane structure. The derivative of PolyNAPGly (5) (n=35) bearing one or two dodecyl groups and some Nε-benzyloxycarbonylhistidyl groups was found to be bound tightly to lipid membrane without destruction of the membrane structure. The addition of these polypeptides to vesicles decreased the membrane fluidity.
Stereoselective Total Synthesis of (±)-Labdane-8α,15-diol and (±)-Eperuane-8β,15-diol
Authors: Hirota Hiroshi , Nakamura Toshio , Tsuyuki Takahiko , Takahashi Takeyoshi
Published: July 2006

(±)-Labdane-8α,15-diol and (±)-eperuane-8β,15-diol, diastereomeric diterpenes to each other, were prepared separately and stereoselectively, via a common 7-membered lactone from the known tricyclic keto alcohol.
A Convenient Method for the Preparation of Secondary Propargylic Ethers. The Reactions of Acetals with 1-Trimethylsilyl-1-alkynes Promoted by the Combined Use of Catalytic Amounts of Tin(IV) Chloride and Zinc Chloride
Authors: Hayashi Masaji , Inubushi Atsuro , Mukaiyama Teruaki
Published: July 2006

In the coexistence of catalytic amounts of SnCl4 and ZnCl2, acetals undergo a coupling with 1-trimethylsilylalkynes to give secondary propargylic ethers in good yields. Similarly, propargylic ethers are directly produced from aldehydes by the treatment with alkoxytrimethylsilanes and 1-trimethylsilylalkynes under the same conditions. This catalyst system also efficiently promotes aldol reaction of silyl enol ethers with acetals or aldehydes, and the Michael reaction of silyl enol ethers with α,β-unsaturated ketones.
ESR Studies of Copper(II) Ion Doped in Single Crystal of Benzo-15-crown-5 Complex
Authors: Li Yong , Tajima Kunihiko , Ishizu Kazuhiko , Azuma Nagao
Published: July 2006

Angular-dependent ESR measurements were carried out at 77 K for 65Cu(II) ions doped in a single crystal of benzo-15-crown-5 (B15C5) magnesium complex. Not only the allowed resonance lines of copper(II) ions, but also the forbidden lines arising from a nuclear quadrupole interaction were observed. Based on an analysis of the single crystal ESR spectra, the spin Hamiltonian containing the quadrupole term was determined for a B15C5–65Cu(II) complex having a 3dz2 ground state in a B15C5–Mg(II) solid matrix.
Bistability and Oscillations in the Bromate–Bromide–Cerium(III) System in Continuous-Flow Stirred Tank Reactor. A Simulation Using a New Set of Rate Constants of the FKN Scheme
Authors: Sasaki Yoshihiro
Published: July 2006

The bahavior of a bromate–bromide–cerium(III) system in a continuous-flow stirred tank reactor was simulated within the framework of the FKN reaction scheme and a new set of rate constants prepared by Field and Försterling. The characteristic properties such as bistability, hysteresis and minimal oscillations could be reproduced. In order to understand bistability in this system, the dynamic behavior of a four-variable model was examined by means of a two-variable approximation.
The Potentiometric Detection of Complex Formation between IgG and anti-IgG Using a Chemically Modified Tantalum Electrode
Authors: Tanaka Toshihiko , Yamamoto Naoto , Tsubomura Hiroshi
Published: July 2006

Tantalum electrodes were chemically modified with anti-IgG to detect IgG (immunoglobulin G) or with IgG to detect anti-IgG by using cyanuric bromide. Changes in the potential as a result of the antigen-antibody reaction can be explained by a simple first-order kinetics equation, while the polarity of the changes at various pH’s can be explained in terms of the charge transfer between anti-IgG and IgG in a way similar to that shown in previous reports for the case of Ti electrodes. The surface modification was confirmed by Auger Electron Spectroscopy (AES).
Redox-Linked Protonation of [Fe4X4(YR)4]2− (X,Y=S and Se; R=n-C12H25 and C6H4-p-t-Bu) in Aqueous Solutions
Authors: Nakamoto Masami , Tanaka Koji , Tanaka Toshio
Published: July 2006

A series of [Fe4X4(YR)4]2− (X,Y=S and Se; R=n-C12H25 and C6H4-p-t-Bu) were prepared as n-Bu4N+ salts. In aqueous Triton X-100 micellar solutions, only the reduced forms of [Fe4X4(YR)4]2− (X,Y=S and Se; R=n-C12H25 and C6H4-p-t-Bu) undergo protonation reactions at the sulfur or selenium atom of the Fe4X4 (X=S and Se) core to exist as an equilibrium mixture of the protonated and unprotonated clusters. On the other hand, not only the oxidized but also the reduced forms of [Fe4X4(YC6H4-p-t-Bu)4]2− (X,Y=S and Se) undergo protonation reactions in aqueous poly[2-(dimethylamino)hexanamide] (PDACA) solutions. The pKox values of [Fe4X4(YC6H4-p-t-Bu)4]2− (X,Y=S and Se) vary depending on the terminal thiolate and selenolate ligands; 5.9 for Y=S and 6.8 for Y=Se, whereas the pKred values of [Fe4X4(YC6H4-p-t-Bu)4]3− are controlled by the core sulfur and selenium; 8.8 for X=S and 7.3 for X=Se. Such characteristic pKox and pKred values suggest that the protonation takes place at the terminal sulfur or selenium atom of the oxidized clusters [Fe4X4(YC6H4-p-t-Bu)4]2− (X,Y=S and Se), while it occurs at the sulfur or selenium atom of the Fe4X4 core of the reduced clusters [Fe4X4(YC6H4-p-t-Bu)4]3− (X,Y=S and Se).
Ion–Solvent Interaction of Amino Acids. The Role of the “Zwitterionic” and the “Ionic” Forms in the Modification of Water Structure over the Temperature Range 25–45 °C
Authors: Bhattacharyya Moni Mohan , Sengupta Mihir
Published: July 2006

Viscosities and densities of aqueous glycine, glycinium chloride, sodium glycinate, betaine, betainium chloride [(CH3)3\overset+NCH2COOH·Cl−], and tetramethylammonium bromide solutions have been measured at 25, 30, and 40 °C over the concentration range 0.01 to 0.1 M. The sequence of the viscosity B-coefficient values obtained is in the order: Banion>Bcation>Bzwitterion for the glycine and betaine systems. The comparatively higher structure promoting behavior of the anion has been discussed in terms of the charge delocalization effect. Apparent molal volumes at infinite dilution have also been calculated, and the ratio B⁄φv° furnishes important information about the nature of solvation around the ion. The present study indicates that in the betaine molecule, the opposing nature of ion–water interaction at the two charge centers renders the system neither a “structure maker” nor a “breaker” in aqueous solution.
Kinetics of Reduction of Silver(II) by Sodium Tetrahydroborate
Authors: Dasgupta Manash , K. Mahanti Mahendra
Published: July 2006

The kinetics of reduction of silver(II) by sodium tetrahydroborate in aqueous acidic solution has been investigated. The reaction was observed to proceed in two steps, namely, (a) the formation of the intermediate AgI and (b) the subsequent conversion of AgI to Ag0. The activation parameters for the two steps have been separately calculated. The intermediate AgI species, and the final products, were characterized by chemical and spectral methods. A plausible mechanism for the reduction of AgII ions has been proposed.
Visible Light Assisted Heterogeneous Catalysis. Decomposition of Peroxomonosulfate over Doped and Undoped WO3 Dispersions in Aqueous Medium
Authors: Maruthamuthu Pichai , Ashokkumar Muthupandian , Venkatasubramanian Lakshmanan
Published: July 2006

Aqueous suspension of RuO2-loaded WO3 powder on illumination with light of λ≥410 nm was found to decompose peroxomonosulfate (PMS, HSO5−) efficiently. The rate and other kinetic parameters indicated that the decomposition process followed Langmuir kinetics; at low concentrations of HSO5− (0.54–2.06×10−3 mol dm−3) the reaction obeyed a first-order kinetics and at higher concentrations, ([HSO5−]>3.00×10−3 mol dm−3) the rate became independent of [HSO5−]. The effects of pH and the molar percentage of the dopant on the rates were also investigated. Small amount of doping by RuO2 (2.5 molar percentage) was found to increase the photocatalytic decomposition of HSO5− whereas the higher amount of doping decreased the rate. Added 2-propanol to the system was found to increase the rate of decomposition of peroxomonosulfate. The proposed mechanism of the decomposition of PMS involves the reactions of the photogenerated valence band holes and the conduction band electrons of WO3, by radiation of wavelength ≥410 nm, in presence and absence of 2-propanol. The rate constants and quantum yields have also been evaluated. The photocatalytic decomposition of peroxomonosulfate is one of the few examples of a unimolecular reaction catalyzed by both the photogenerated holes (hvb+) and electrons (ecb−).
Normal Pressure Double Carbonylation of Aryl Halides Using Cobalt(II) Chloride in the Presence of either Sodium Sulfide or Sodium Borohydride
Authors: Itoh Kenji , Miura Masahiro , Nomura Masakatsu
Published: July 2006

Tetracarbonylcobaltate ion generated by a treatment of cobalt(II) chloride with either sodium sulfide or sodium borohydride under a normal pressure of carbon monoxide was capable of catalyzing carbonylation of aryl halides in the presence of calcium hydroxide and methyl iodide to give arylglyoxylic acids in good selectivity.
The Hammett Relationship in the Reduction of Aldehydes with 2-Propanol by Catalysis with Hydrous Zirconium Oxide
Authors: Shibagaki Makoto , Kuno Hideyuki , Takahashi Kyoko , Matsushita Hajime
Published: July 2006

A linear correlation of the Hammett relationship was obtained for a catalytic reduction of substituted benzaldehydes with 2-propanol with hydrous zirconium oxide. The reaction constant ρ was 1.35, indicating that the electronic effect on the reaction is larger than that on the standard one.
The Synthesis and Characterization of Manganese(III) Complexes with the General Formula of [Mn(X)(L)]n+ (n=0, 1) (X=Cl−, N3−, Pyridine, N-Methylimidazole, L=N,N′-[(Methylimino)bis(trimethylene)]bis[salicylideneaminate]: The X-Ray Crystal Structure of [Mn(N-MeIm)(L)][BPh4]
Authors: Akui Toshifumi , Ohyoshi Akira , Matsumoto Naohide , Okawa Hisashi
Published: July 2006

A series of manganese(III) complexes with the general formula of [Mn(X)(L)]n+ (n=0, 1) have been prepared and characterized, where X=Cl−, N3−, pyridine, N-methylimidazole, and L=quinquedentate Schiff base ligand N,N′-(methynmmo)bis(trimethylene)]bis[salicylideneaminate]. The X-ray analysis of [Mn(N-MeIm)(L)][BPh4] confirmed that the coordination geometry of the manganese(III) ion is a tetragonal bipyramid in which two axial positions are occupied by a central amine nitrogen atom N(3) and an imidazole nitrogen atom N(4), with elongated bond distances of Mn–N(3)=2.388(6) Å and Mn–N(4)=2.251(6) Å.
The Charge Carried by a Layer Formed by an Aggregation of Polyelectrolytes in a Solution Containing a Salt
Authors: Kaneko Tetsuo
Published: July 2006

A layer formed by the aggregation of polyelectrolyte molecules is charged according to the ionic dissociation of the layer in a simple salt solution. The charge carried by the layer is estimated on a basis of solutions of the Poisson-Boltzmann equation. It has been found that this charge is independent of the concentration, ns, of a salt, in spite of the permanence of the layer to counter ions when the density, ng, of charged groups in the polyelectrolyte molecules is much higher than the concentration ns. As the result, the charge may be given as a function of three parameters (temperature, density ng, and thickness of the layer) except for ns. Moreover, it has been found that the distribution of counter ions within the layer and their distribution in the vicinity of the layer may be independent of ns and that these distributions of counter ions may agree with that in a salt-free solution.
Application of the SPE Method to Organic Electrochemistry. IX. Reaction Profiles of an Iron Redox Couple Incorporated into Pt–Nafion with Ascorbic Acid
Authors: Ogumi Zempachi , Mizoe Toshiyuki , Takehara Zen-ichiro
Published: July 2006

Fe3+ has been incorporated into Pt–Nafion. The behavior of Fe3+ as a mediator was examined in detail in a system comprising the oxidation of l-ascorbic acid (AA) to dehydroascorbic acid (AD). The diffusion of AA in Nafion is slower than that of Fe3+. The concentration profiles of Fe3+ and AA in Pt–Nafion have been clarified and a reaction of the mediator with AA took place within a very narrow zone close to the surface. The averaged diffusion coefficients of Fe3+ and AA are 1.5×10−7 cm2 s−1 and 4.7×10−8 cm2 s−1, respectively.
A Novel Approach to the Enumeration of Reaction Types by Counting Reaction-Center Graphs Which Appear as the Substructures of Imaginary Transition Structures
Authors: Fujita Shinsaku
Published: July 2006

A novel method of enumerating reaction types is presented. The reaction types are formulated as reaction center graphs (RCGs) that are derived from a parent basic reaction graph (BRG) or from a parent reaction graph (RG) by the substitution of various atoms on the vertices and/or by the attachment of single, double, or triple par-bonds to the edges. The counting of the isomeric RCGs is solved by applying Pólya’s theorem to the derivation of a cycle index, in which different variables are introduced to the different orbits of the permutation group of a parent BRG (or RG). Various atom-figure and bond-figure inventories are described in order to count the isomers of RCGs. The numbers of the RCGs are given in the form of the coefficients of a generating function called an RCG-counting polynomial series.