bluuebunny/crossref_metadata_2025 huggingface dataset:
Observation on the Fragmentation of Some Tosylhydrazones Using Electrochemically Generated Superoxide Ion
Authors: Singh Manorama , Mishra S C , Misra Ram A
Published: July 2006

Superoxide ion (O2\ewdot) generated in situ by electrochemical reduction of molecular oxygen in dimethylformamide (DMF) at mercury cathode, behaves as a mild effective base to deprotonate the acidic hydrogen from tosylhydrazones of benzophenone (1), benzaldehyde (2), cyclohexanone (3), benzoin (4), acetophenone (5), and benzil (6) finally affording tetraphenylethene (1a), trans-stilbene (2a), cyclohexene (3a), deoxybenzoin (4a), acetophenone azine (5a), and 4,5-diphenyl-1-tosylamino-1,2,3-triazole (6a) respectively in good to excellent yield.
A 13C NMR Study of Octyltrimethylammonium Bromide Solutions with and without Urea
Authors: Uzu Yuhei , Saito Yasushi , Terao Hideyasu , Yokoi Masatoki
Published: July 2006

The effect of urea on the micelle formation of octyltrimethylammonium bromide (C8TAB) solution in D2O was studied by 13C NMR chemical shift and 13C spin-lattice relaxation time. The presence of urea increases the critical micelle concentration (cmc) of C8TAB solution. In the micellar state, the segmental motions of methylene chain adjacent to the polar head group are strongly affected by urea.
Convenient Preparation of Acetals over Hydrous Zirconium Oxide
Authors: Shibagaki Makoto , Takahashi Kyoko , Kuno Hideyuki , Matsushita Hajime
Published: July 2006

Aldehydes and ketones were efficiently converted to the corresponding acetals by the reaction with ethylene glycol over hydrous zirconium oxide. The reaction could proceed under reflux condition or at room temperature. The compound, which was unstable in acid, was also acetalized by this catalyst.
Synthesis of (5Z,13S)-5-Tetradecen-13-olide, Aggregation Pheromone of the Cryptolestes Grain Beetle, Employing Asymmetric Bioreduction with Immobilized Bakers’ Yeast Entrapped in Calcium Alginate Beads
Authors: Naoshima Yoshinobu , Nakamura Akihiro , Munakata Yoshihito , Kamezawa Makoto , Tachibana Hojun
Published: July 2006

(5Z,13S)-5-Tetradecen-13-olide, a synergist of the aggregation pheromone of the flat grain beetle, was synthesized in an optically pure form by means of an asymmetric bioreduction of the intermediate acetylenic keto acid with immobilized bakers’ yeast entrapped in gels of calcium alginate.
Photolysis of Diary Triphenylmethylphosphonates
Authors: Shi Min , Okamoto Yoshiki , Takamuku Setsuo
Published: July 2006

Synopsis. Upon UV irradiation in methanol,diaryl triphenylmethylphosponate underwent three types of elimination of two aryl groups to give biaryls: the first is an α,α-elimination of two phenyl groups from a triphenylmethyl group which leads to formation of the corresponding carbene intermidiate; the second is an elimination of two aryl groups from a diaryl ester group to afford biaryl; the third is an elimination of phenyl and aryl groups from both moieties to give arylbenzene.
Hydrogenation of Monoalkylbenzenes over Supported Pt Catalysts. Influence of Different Variables on the Catalytic Activity
Authors: Aramendía M Angeles , Borau Victoriano , Jiménez César , Marinas J María , Rodero Francisco , Sempere M Eugenia
Published: July 2006

The catalytic activity of various supported Pt systems used in the hydrogenation of monoalkylaromatic hydrocarbons is markedly influenced by different variables involved in the catalyst synthesis (support, solvent, metal salt, and reduction temperature of the precursor). By analyzing the influence of the substrate structure, we found the following reactivity order: t-butylbenzene>isopropylbenzene>ethylbenzene>toluene>benzene. The results obtained conform to the Hammet equation.
A Study of the Atherton–Todd Reaction Mechanism
Authors: Troev K , Kirilov E M G , Roundhill D M
Published: July 2006

It has been shown that alkylammonium methyl phosphonates [CH3OP(O)HO]− [NCH3R3]+ and sodium ethyl phosphonate [CH3CH2OP(O)HO]− Na+ catalyse the Atherton–Todd reaction. It has been established that the alkylammonium salts themself react with carbon tetrachloride to give chloroform, resulting in the postulate that base activation leads to the monoalkyl phosphonate anion.
Electrochemical Behavior of High Transition Temperature Superconducting Oxides
Authors: Ohkawa Kiyomi , Itoh Kiminori , Fujishima Akira
Published: July 2006

Typical high transition temperature (high-Tc) superconducting oxides were used as electrodes in order to investigate their electrochemical behavior at room temperature. Chemical stability of these materials in various solutions was also tested. These superconducting oxides were stable in nonaqueous solutions, but is was very difficult to protect electrical contacts from the solvents because of porous structures of these oxides. These materials were rather stable in highly concentrated alkaline solutions while unstable in neutral and acid solutions. Electrochemical experiments were carried out in alkaline solutions, and the following results were obtained: (1) All of the high-Tc superconducting oxides were unstable at cathodic polarization. (2) Oxygen evolution was observed under anodic polarization. (3) These oxides behaved like p-type semiconductros though no photocurrents were detected. (4) [Fe(CN)6]3−⁄4− served as a redox couple for all of these high-Tc oxides.
Picosecond Laser Photolysis Studies on the Photoreduction of Excited Benzophenone by Diphenylamine in Solutions
Authors: Miyasaka Hiroshi , Mataga Noboru
Published: July 2006

The mechanism of photoreduction of benzophenone (BP) by diphenylamine (DPA) in isooctane as well as acetonitrile and other polar solvents has been investigated by means of picosecond laser photolysis and time-resolved transient absorption spectral measurements. The results of measurements have demonstrated clearly that the hydrogen abstraction and charge transfer (CT) or ion pair (IP) state formation by electron transfer are competing at encounter between triplet benzophenone (3BP*) and DPA both in nonpolar and polar solvent, and the CT or IP state relaxed with respect to the donor acceptor configurations and solvation does not contribute to the ketyl radical formation. It has been concluded that the very short-lived CT state at encounter between 3BP* and DPA plays a crucial role in the hydrogen abstraction reaction, i.e. the mutual orientation of 3BP* and DPA in this very short-lived CT state at encounter will determine the successive process, the formation of the ketyl radical or relaxed CT or IP state.
Synthesis of Optically Active Hexahydrofuro[2,3-b]furan, A Nonchromophore Moiety of Asteltoxin
Authors: Nishiyama Shigeru , Kanai Hiroki , Yamamura Shosuke
Published: July 2006

An optically active nonchromophore moiety of asteltoxin carrying a hexahydrofuro[2,3-b]furan structure has been successfully synthesized from a branched-chain d-xylohexofuranose derivative.
Highly Stereoselective Synthesis of Two Natural Olefinic Diols via N-Oxide [2,3]Sigmatropic Rearrangement
Authors: Sato Kikumasa , Inoue Seiichi , Iwase, Norimichi , Honda Kiyoshi
Published: July 2006

The [2,3]sigmatropic rearrangement of α-substituted N,N-dimethylmethallylamine N-oxides results in a highly stereoselective formation of trans olefins oxygenating at the allylic position, and providing a quite efficient synthesis of cuspidiol and plaunotol.
Medium Effects on the Molecular Electronic Structure. III. Quantum-Chemical Analysis of Solvent-Induced 13C NMR Chemical Shift Changes of Some Polyene Compounds
Authors: Sakurai Minoru , Hoshi Hajime , Inoue Yoshio , Chûjô Riichirô
Published: July 2006

A reaction-field theory (Hoshi et al., J. Chem. Phys., 87, 1107 (1987)) is applied to the analysis of solvent-induced 13C chemical shift changes of some polyene compounds. The solvent dependence of the 13C chemical shifts is calculated by means of the INDO-finite perturbation method combined with this theory. It is shown that the calculations well reproduce characteristic 13C shift changes observed in aprotic solvents. This indicates the validity of the theory. In addition, the origin of the solvent-induced 13C shifts is discussed on the basis of the electronic distribution obtained.
Magnetic Field Effects on the Dynamics of Biradicals Generated from Benzophenone and Diphenylamine Bifunctional Chain Molecules
Authors: Tanimoto Yoshifumi , Okada Natsuo , Takamatsu Shinji , Itoh Michiya
Published: July 2006

The magnetic field effects (MFE) on the lifetimes of triplet biradicals generated from the intramolecular photoreaction of bifunctional chain molecules, α-(4-benzoylphenoxy)-ω-[4-(phenylamino)phenoxy]alkanes (BP–O–n–O–DPA, n=2–16) were studied by laser flash photolysis. MFE on the biradical lifetimes are strongly affected by magnetic field, chain length, and solvent. The effects are interpreted in terms of the hf-relaxation mechanism. Lifetime change due to T−–S level crossing was observed in the biradicals with n=2 and 4. The singlet and triplet degeneracy of biradicals occurs when n≥6.
Fluorescence Behaviors of 3,3-Bis(8-quinolyloxymethyl)oxetane: Effects of Solvents, Carrier-Concentration, and Metal Ions on the Fluorescence Intensity
Authors: Hiratani Kazuhisa , Nomoto Masayo , Ohuchi Shoukichi , Taguchi Kazuhiro
Published: July 2006

The effects of solvents, the concentration of 3,3-bis(8-quinolyloxymethyl)oxetane (1), and the presence of metal ions on the fluorescence intensity of 1 have been investigated. The fluorescence intensity of 1 considerably increased when measured in chloroform, acetonitrile, or dioxane, though resulting in a comparably small increase when measured in ethyl acetate, toluene, or ethylene glycol. When acetone was used as the solvent, the fluorescence spectrum was hardly observed. When the concentration of 1 was adjusted to near 0.1 mmol dm−3, the intensity became maximum in each solvent used, except for acetone. It was observed that the fluorescence intensity of 1 rapidly decreased in a concentration range over 0.1 mmol dm−3. Furthermore, when metal ions were added into an organic solution such as acetonitrile, dioxane, or chloroform containing 1, the maximum increase in the fluorescence intensity was observed in the presence of lithium salt, whereas the intensity hardly changed in the presence of both potassium and sodium ions, compared with that of 1 in the absence of any metal ion. The presence of magnesium and barium ions also hardly brought about an increase of the intensity. On the other hand, heavy metal ions, such as silver(I) and copper(II), were observed to results in a slight decrease.
The Anisotropy of the Crystal Growth of Fe3O4 in an Aqueous Solution
Authors: Tamaura Yutaka , Itoh Tomoyuki , Matsuda Tsutomu , Abe Masanori
Published: July 2006

The anisotropy of the crystal growth of the spinel-type ferrites in an aqueous solution was studied using ferrite films piled up on the glass substrate by means of the thin liquid-film method (TLF method). From the difference between the values of the Oind (the parameter for the degree of the oxidation state), it was found that the Fe3O4 crystal grows in the (111) direction in the “oxidation state” (Oind=1.4×10−2 dm3 min−1), but in the (100) direction in the “Fe2+-rich state” (Oind=3.38×10−4 dm3 min−1). Although the reaction conditions for the formation of the Co(II)– and Zn(II)–ferrites were the same (both used in the “oxidation-state”; Oind=5.5–5.8×10−2 dm3 min−1), the anisotropy of the crystal growth was different between Co2+ [the (111) direction] and Zn2+ [the (100) direction]. These results were explained in terms of difference in the degree of the oxidation state (Oind). For the inverse spinel, the slower rate of the formation of the sublattice of the B site in the “oxidation-state” seems to cause the preferential formation of the A site, since the Fe3+ ions are preferentially incorporated into the A site. This results in the anisotropy in the (111) direction of Fe3O4 and Co(II)–ferrite (inverse spinel). On the contrary, in the “Fe2+-rich state”, the preferential formation of one of the two B sites (the Fe2+ occupies one of the two B sites in the inverse spinel) results in the anisotropy in the (100) direction of Fe3O4. For the normal spinel, the acceleration of the incorporation of the Fe3+ ions into the B site in the “oxidation-state” will result in the anisotropy in the (100) direction. This is the case for the anisotropy in the (100) direction of the Zn(II)–ferrite.
Hydroxide Ion-Selective Polymeric Membrane-Coated Wire Electrode Based on Oxomolybdenum(V) Tetraphenylporphyrin Complex
Authors: Abe Hideo , Kokufuta Etsuo
Published: July 2006

A coated wire electrode (CWE) was prepared by use of a poly(vinyl chloride)-supported liquid membrane containing oxoethoxo(5,10,15,20-tetraphenylporphyrinato)molybdenum(V) as a carrier. CWE based on such a metallo-porphyrin complex exhibits near-Nernstian responses to varying concentrations of NaOH, NaF, and C2H5OH, especially to NaOH over a wide concentration range. The pOH response curve was influenced by certain anions other than OH− ion, but not by cations such as Li+, Na+, K+, and Cs+. The mixed solution method gave a selectivity sequence OH−>>ClO4−>NO2−>F−∼SCN−>I−>NO3−>SO3−>Br−>SO42−, with a preference for OH− over ClO4− by 104.6 and over F− (or SCN−) by 106.2. In addition, Cl− ion was found to have little interfering effect under conditions used in the measurements of selectivity coefficients. Both response-time profile and pOH-response curve scarcely varied even when CWE was stored in distilled water for 167 days.
The Specific Interaction of Mg and Alkaline Earth Metal Ions with Well-Defined Surfaces of α-HCrO2 and Cr2O3
Authors: Kittaka Shigeharu , Yamanaka Shigeru , Yanagawa Naoto , Okabe Takahiro
Published: July 2006

The selectivity sequences of Mg and alkaline earth ions to the surface of α-HCrO2 and Cr2O3 were investigated by measuring the electrophoretic mobility and the surface charge density. The latter was determined by means of potentiometric titration. The selectivity sequence of Mg and alkaline earth ions to the α-HCrO2 surface was determined as Mg>Ca>Sr∼Ba. This sequence was explained by the close configurational fitting of adsorbed metal ions to the solid surface. The reason is that the O–O distance on the (001) plane of Mg(OH)2 and Ca(OH)2 is similar to that of the α-HCrO2. On the amorphous Cr2O3 and crystalline Cr2O3, exposing mainly the (001) plane, the affinity of varying ions was comparable. The isoelectric points (IEP) of the chromium(III) hydroxide oxides and oxides were discussed in connection with their surface crystallinity as determined by electron microscopy. A lower crystallinity gives a slightly higher IEP.
Pillared Tetrasilicic Mica Catalysts Modified by Fixed Interlayer Cations. Classification of Fixation Mode by Cations
Authors: Sakurai Hiroaki , Urabe Kazuo , Izumi Yusuke
Published: July 2006

Fluor-tetrasilicic mica (TSM) exchanged with various types of cations was calcined at 300 °C for 3 h, and a part of the cations were fixed, followed by Al-pillaring. Thus, acidic pillared clay catalysts were prepared with a modification of the silicate layer by cations. Active catalysts for cumene cracking were obtained when modified by Sr2+, Ca2+, La3+, and Li+. The structural changes in the catalysts affecting the reaction activity was examined through X-ray diffraction, surface area, and 29Si-MASNMR measurements. The mode of cation fixation could be classified into five types, depending on the valence and size of the cations to be fixed. A group-2 cation (Na+) gave no modification effect compared with conventional nonmodified PTSM and managed only meager catalytic activity. The catalyst modified by group-5 by (Sr2+, Ca2+, La3+ etc.) cations or a group-1 (Li+) cation had a distinct pillared structure, characterized by an 18 Å basal spacing. These cations could be fixed either onto the basal oxygen surface for group-5 cations or into the octahedral vacancy for a group-1 cation. Though group-4 (Al3+, Mg2+) and group-3 (Cs+, K+) cations should also be fixed into the vacant sites and onto the surface, respectively, both types of modified catalysts formed unstable pillared structures, giving low catalytic activities.
Dynamic Process of Delayed Geminate Ion Pairs in X-Irradiated Squalane Solution of p-Terphenyl: An ODESR Study
Authors: Okazaki Masaharu , Nunome Keichi , Matsuura Kaoru , Toriyama Kazumi
Published: July 2006

The fluorescence detected ESR (ODESR) spectrum of a squalane solution of p-terphenyl was observed at various temperatures, concentrations, and microwave powers. Analysis of the ODESR amplitude, the line shape, and the area under the spectrum which is normalized by the fluorescence intensity led us to conclude that two geminate pairs (one with a terphenyl anion and a hole of the solvent squalane and the other with a terphenyl anion and its cation) contribute to the ODESR spectrum. It was also concluded that the former pair has a much shorter recombination time than that of the latter. It is suggested that though the hole center hops among the solvent squalanes, the rate is much less than that for the hole in aromatic solvents.
The Raman Spectral Study on the Solution Structure of Iron(III)-edta Complexes
Authors: Kanamori Kan , Dohniwa Hidekazu , Ukita Naoya , Kanesaka Isao , Kawai Kiyoyasu
Published: July 2006

The Raman spectra of iron(III) complexes with ethylenediaminetetraacetate were observed for the purpose of elucidating the structure of the complexes in solution. In a Raman spectral study on the solid complexes, the spectra in the 300–600 cm−1 region were found to be diagnostic to coordination geometry. Namely, the coordination number can be determined on the basis of the wavenumber difference of the two major bands observed in the 450–600 cm−1 region; the wavenumber differences observed for heptacoordinate complexes lie between 32 and 42 cm−1, while that for the hexacoordinate complex is 62 cm−1. Complexes containing a sexidentate edta exhibit a single intense band around 470 cm−1 in the 450–500 cm−1 region, while complexes containing a quinquedentate edta exhibit two intense bands in this region. These Raman spectral criteria were then applied for the determination of the solution structure. The Raman spectral features observed for solutions of Fe(III)-edta complexes indicate that the any alkali metal salts and acid salts of FeIII(edta)− give sexidentate heptacoordinate complex ions in water. The dimeric complex which is formed in an alkaline solution was characterized as being a dinuclear complex consisting of two quinquedentate hexacoordinate iron(III) moieties with a Fe–O–Fe bridging unit.
13C-CP-MAS NMR Spectroscopic Study of the Reaction Products of Osmocene with Lewis Acids
Authors: Watanabe Masanobu , Sano Hirotoshi
Published: July 2006

The adducts of osmocene derivatives with Lewis acids were studied by means of 13C-CP-NMR spectroscopy and other physicochemical techniques. The large low-field shifts found through 13C-CP-MAS NMR and 1H NMR spectroscopy and the organotin(IV) species found in the 119Sn-Mössbauer spectroscopic data suggest the presence of direct chemical bonds between the osmium atoms and the Lewis acids in the adducts.
ESR Studies on Salicylaldehyde Schiff Base Complexes of Copper(II). III. Dimer Formation on Bis(N-alkylsalicylideneaminato) copper(II) Complexes and Their Derivatives in Toluene
Authors: Yokoi Hiroshi , Takeuchi Akira , Yamada Shoichiro
Published: July 2006

Twenty one of the title complexes (abbreviated as Cu(X–sal–R)2; X=H, 5-Cl, or 5-Br and R=N-alkyl) in toluene have been extensively studied by the ESR method in order to obtain fundamental information on dimer formability and the dimeric structures of these complexes. The equilibrium constant (K) for 2 monomer \ightleftharpoons dimer has been determined by analyzing the concentration dependence of the intensity ratios of the dimer to the monomer ESR signals for frozen toluene solutions. The K values of the Cu(H–sal–R)2 complexes are remarkably R-dependent as follows: methyl (233)>>ethyl (10)∼isobutyl (9)>other normal alkyl groups (∼4) for a series of the R groups with primary α-carbons, and cyclohexyl (75)>>isopropyl (7)>s-butyl (<<1)>cycloheptyl (∼0)>t-butyl (0) for a series of the R groups with secondary and tertiary α-carbons, where the complex is denoted by R, followed by K (M−1) in parentheses. The complexes with R=nonyl or higher homologues form some polymeric species besides dimers and monomers. The K values remarkably increase by the introduction of X=5-Cl or 5-Br. The observed dimer ESR spectra have been analyzed by computer simulation in order to estimate the structural parameters (r and ξ) of parallel-planar dimers, where r is the Cu–Cu distance and ξ is the angle between the Cu–Cu direction and the normal to the molecular plane. These results indicate that most complexes form two types of dimers with different structures: type a, r=3.75 Å and ξ=37°; type b, r=4.10 Å and ξ=23°. The Cu(X–sal–methyl)2 complexes form only a-type dimers, while the others simultaneously form both types of dimers, except the complexes of R=isopropyl and cyclohexyl which form another type of parallel-planar dimers having a slightly tetrahedrally-distorted coordination geometry around each copper atom.
Synthesis and Tautomerism of 1,5-Bis(alkylamino)-4H-benzo[a]phenothiazin-4-ones
Authors: Hasegawa Kan-ichi , Sakakibara Makoto , Ishida Tetsuya , Ueno Yoshio
Published: July 2006

The equimolecular condensation of 2-aminobenzenethiol (1) with 4,8-bis(alkylamino)-1,5-naphthoquinones (2) in ethanol in the presence of HCl gave near-infrared-absorbing 1,5-bis(alkylamino)-4H-benzo[a]phenothiazin-4-ones (3), which existed as predominant tautomers in various solvents. The reaction mechanism was proposed to involve pathways through the O-protonation of 2, followed by the attack of 1 on the resulting ion, the subsequent oxidation, and the acid-catalyzed intramolecular cyclization of the quinonoid intermediate. The tautomeric equilibria of 2, 3, and 5,8-dihydroxy-1,4-naphthoquinone favor the formation of an interconverting hydrogen atom of a higher electron density. The solvatochromic effect of 3 was analyzed by means of the linear solvation energy relationships.
Aromatic Skeletal Structures in Distillable Coal-Derived Liquids
Authors: Sugimoto Yoshikazu , Miki Yasuo , Oba Masaaki , Yamadaya Shoko
Published: July 2006

Aromatic constitutents in Wandoan coal-derived distillate were analyzed by means of capillary gas chromatography/mass spectrometry (GC/MS) in order to clarify their aromatic skeletal structures. The major aromatic skeletons could be classified into several groups, the molecular weights of which were represented by 78+50n, 118+50n, 154+50n, 166+50n, 202+50n, 242+50n (n=0,1,2,···), and so on. The increase by 50 corresponded to an additional benzene ring fused to the original skeleton. Some new types of aromatic skeletons, such as dihydrophenalene and benzindan, were found to be present in significant amounts.
Ion Pair Extraction and Separation Studies of Palladium
Authors: Sundaramurthi N M , Shinde V M
Published: July 2006

A simple and rapid method is proposed for the extraction, separation, and spectrophotometric determination of palladium from salicylate media using Aliquat 336 dissolved in xylene as an extractant. The optimum conditions were evaluated from a critical study of pH, salicylate concentration, Aliquat 336 concentration, and period of equilibration. The palladium in the Aliquat 336 phase is determined spectrophotometrically with 4-(2-pyridylazo)resorcinol (PAR) at 530 nm. The proposed method described the scheme for the separation of platinum, nickel, copper, cobalt, zinc, and manganese from binary mixtures. The method was extended to the analysis of palladium catalyst and platinum ores.
Tin(IV) Antimonate as a Lead-Selective Cation Exchanger: Synthesis, Characterization, and Analytical Applications
Authors: Varshney K G , Gupta Upma
Published: July 2006

A new phase of a lead-selective cation exchange material, tin(IV) antimonate has been prepared, which possesses a good column exchange capacity (2.4 mequiv g−1). Its characterization has been done on the basis of its ion-exchange characteristics and some instrumental studies such as TGA, IR, and X-ray diffraction. The utility of the material has been demonstrated by achieving some binary separations of metal ions on its column, such as Al(III)–Pb(II), Mg(II)–Pb(II), Fe(III)–Pb(II), Al(III)–Fe(III), Mg(II)–Al(III), and Mg(II)–Fe(III). Maximum limits of the column’s loading capacity have also been evaluated for all metal ions.
New Ferroelectric Liquid Crystal Materials: (+)-4-(5-Alkyl-1,3-dioxan-2-yl)phenyl 4-(2-Methylbutoxy)benzoates
Authors: Haramoto Yuichiro , Kamogawa Hiroyoshi
Published: July 2006

(+)-4-(5-Alkyl-1,3-dioxan-2-yl)phenyl 4-(2-methylbutoxy)benzoates (9) and their oxathiane (10) and dithiane (11) analogs have been synthesized. The mesomorphic behavior of these compounds was measured. Compounds 9 exhibited a ferroelectric liquid-crystal behavior (e.g. R=n-C10H21: 51 SmC* 57.5°C), while the corresponding 1,3-oxathianes (10) and 1,3-dithianes did not.
NMR Studies on the Rotational Motion of Coordinated D2O Molecules in MBr (M=Li+, Na+, K+, Cs+) Dilute Aqueous Solutions
Authors: Shimizu Akio , Taniguchi Yoshihiro
Published: July 2006

The parallel (D,τ⁄⁄) and perpendicular (17O,τ⊥) rotational correlation times of coordinated D2O molecules in MBR (M=Li+, Na+, K+, Cs+ aqueous solutions in the concentration range of 0.2 to 1.0 molkg−1 at 25 °C were determined by NMR. The spin-lattice relaxation rates (R1) varied linearly with increase in concentration up to 1.0 molkg−1. The ratios (τ⁄⁄/τ⊥) of the rotational correlation times of coordinated D2O molecules in Li+, Na+, K+, and Cs+ ions were 1.12, 1.13, 0.89, and 0.92, respectively. These results indicate that for coordinated D2O molecules in Li+ and Na+ ions, the perpendicular rotational motion is 10% faster than the parallel one. On the other hand, for coordinated D2O molecules in K+ and Cs+ ions, the tendency was reversed. These results are explained in terms of both the Eulerian angle β between the diffusion tensors with the molecular plane and the intermolecular interactions between the ions and D2O molecules.
Reaction of [CoL2]· 2H2O, [Co(NO)L2], or [Co(NO)L2(py)] (L=8-Quinolinolate Ion; py=Pyridine) with Nitrogen Monoxide: Disproportionation of Nitrogen Monoxide Induced by Cobalt Complexes
Authors: Maejima Toshiaki , Miki Eiichi , Tanaka Mikio , Tezuka Hirobumi , Mizumachi Kunihiko , Ishimori Tatsujiro
Published: July 2006

[Co(qn)2]· 2H2O (1) (qn=8-quinolinolate ion) and [Co(NO)(qn)2] (2) reacted with NO in 10 vol% pyridine–DMF or pyridine to give the nitrato complex, [Co(NO3)(qn)2L] (L=pyridine or DMF), with liberation of N2O. [Co(NO)(qn)2(py)] (py=pyridine) having NO− group (3) reacted with NO in CH2Cl2, the py–DMF, or pyridine to give [Co(qn)2(NO3)(py)] with liberation of N2O. The mass analyses of the residual NO for the reaction of 2 or 3 with NO in the pyridine medium and for the reaction of 3 with NO in CH2Cl2, using the nitrogen-15 labelled compounds showed that a perfect nitrogen scramble occurred between the NO gas and the NO group of 2 or 3. In the reaction of 2 with NO in CH2Cl2, ca. 80% of the coordinating NO reacted with NO gas accompanying a rupture of the original Co–NO bond. The present results were compared with those obtained in the cases that 2-methyl-, 4-methyl-, 5-chloro-, and 5-nitro-8-quinolinolate ions were used as ligands. The electronic effects caused by the substituent of the quinoline ring and by the solvents on the reactions were discussed.
Synthetic Photochemistry. LIV. The Photoaddition Reaction of Methyl 2,4-Dioxopentanoate with 2,5-Dimethyl-2,4-hexadiene, a Sterically Crowded Conjugated Diene
Authors: Hatsui Toshihide , Nojima Chitoshi , Takeshita Hitoshi
Published: July 2006

The photoaddition reaction of methyl 2,4-dioxopentanoate with 2,5-dimethyl-2,4-haxadiene gave a normal [2+2]adduct in only a small amount, but three isomeric dihydropyrans (4–6), two oxetanes (7 and 8), and five isomeric hydroxy keto esters (9–13). The mechanism and regioselectivity were discussed.
The Preparation of Crown Ethers Containing Dicinnamoyl Groups and Their Complexing Abilities
Authors: Akabori Sadatoshi , Tsuchiya Shigemi
Published: July 2006

The reaction of 1, 10-bis[p-[2-(chloroformyl)vinyl]phenyl]-1,4,7,10-tetraoxadecane with the dipotassium salt of catechol in the presence of a catalytic amount of 18-crown-6 in benzene gave 5,6-benzo-4,7,17,20,23,29-hexaoxa[10.10]paracyclopha-1,5,9-triene-3,8-dione (10a) in 3.6% yield. Also, 24,25-benzo-1,4,7,10,13,23,26-heptaoxa[13.10]paracyclopha-20,24,28-triene-22,27-dione (10b) and 27,28-benzo-1,4,7,10,13,16,26,29-octaoxa[16.10]paracyclopha-23,27,31-triene-25,30-dione (10c) were obtained by the same method in 3.1 and 3.0% yields, respectively. Irradiation of the acetonitrile solutions of the crown ethers, 10a, 10b and 10c, by Pyrex-filtered UV light (>300 nm) gave the corresponding intramolecular [2+2]photocycloadducts, 11a, 11b and 11c, in 95.8, 93.2 and 90.1% yields, respectively. The structures of 11a, 11b and 11c were confirmed to be the β-form by their 1H NMR spectra. The photoreversible cleavage of 11a, 11b and 11c by 220 nm UV light gave the corresponding starting crown ethers, 10a, 10b and 10c, in 30, 40 and 61% yields, together with their geometrical isomers in 30, 50 and 27% yields, respectively. Compound 10c showed selective extraction abilities for K+ and Rb+ cations compared with 11c.
Salt Effects on Equilibrium and Kinetics of the Reaction of Tetrakis(1-methyl-4-pyridinio)porphine with DNA
Authors: Sugimoto Naoki , Hasegawa Keiko , Sasaki Muneo
Published: July 2006

The association reaction of tetrakis(1-methyl-4-pyridinio)porphine (TMpyP) with salmon testes DNA has been investigated spectrophotometrically, statically, and kinetically in buffers containing different concentrations of Na+. Free TMpyP had an absorption maximum at 424 nm, which decreased with increasing DNA concentration. At the low Na+ concentrations of less than 1.20×10−1 mol dm−3 the minimal absorbance at the wavelength was reached by less than 1×104 mol dm−3 DNA. On the other hand, near the end of the titration at the high DNA concentrations at 2.20×101 mol dm−3 Na+, the absorbance no longer continued to decrease but displayed a small absorbance increase. The dependence of the association constant on the Na+ concentration indicated that less than one ion-pair contributed to a formation of the complex between TMpyP and DNA if there was the same reaction mechanism at the Na+ concentration range used in the experiment. These results of the spectra and the association constants suggested that a mechanism of the reaction might be different at the low and high salt concentrations. Kinetic results by a micro stopped-flow method showed that the reaction was a single step at the low Na+ concentration, while at the high Na+ concentration it consisted of two steps.
The Reaction of Wittig Reagents with Selenium. Formation of Selenoaldehydes
Authors: Okuma Kentaro , Komiya Yasuo , Kaneko Isao , Tachibana Yuji , Iwata Eiji , Ohta Hiroshi
Published: July 2006

The reaction of Wittig reagents with elemental selenium gave the corresponding selenoaldehydes which further reacted with other Wittig reagents to give the corresponding dimeric olefins in good yields. The selenoaldehydes formed afforded corresponding adducts by the reaction with dienes. These selenoaldehydes obtained by retro Diels–Alder reaction were also found to react with Wittig reagents to give the corresponding olefins in good yields.
Stereochemical Control in Microbial Reduction. XV. Preparation of (2R,3S)-2-Allyl-3-hydroxybutanoate
Authors: Nakamura Kaoru , Miyai Takehiko , Fukushima Kohichi , Kawai Yasushi , Babu B Ramesh , Ohno Atsuyoshi
Published: July 2006

The reduction of ethyl 2-allyl-3-oxobutanoate mediated by Mucor javanicus affords the corresponding (2R,3S)-syn-hydroxy ester. The stereoselectivity is excellent and complementary to the reduction mediated by bakers′ yeast where the (2S,3S)-anti-hydroxy ester is obtained.
Inverse Phase-Transfer Catalysis by Cyclodextrins. Palladium-Catalyzed Reduction of Bromoanisoles with Sodium Formate
Authors: Shimizu Shoichi , Sasaki Yasuyuki , Hirai Choichiro
Published: July 2006

Bromoanisoles have been reduced to hydrocarbons with sodium formate in high yields under mild conditions using palladium on charcoal and cyclodextrins as catalysts. In aqueous phase-organic phase reactions employing a solid-phase catalyst (Pd/C), cyclodextrins function as inverse phase-transfer catalysts which transfer the substrate into the aqueous phase.
The Behavior of Mixing in Liquid Binary Alloys. Enthalpies of Mixing in the Systems Lead–Tin, Lead–Antimony, Lead–Bismuth, and Lead–Thallium
Authors: Badawi Walid , El-Talbi Mohamed , Oun Ahmed M
Published: July 2006

The paper presents values of the enthalpy of mixing in the liquid systems Sn–Sb, Pb–Bi, and Tl–Pb. The enthalpy of mixing in the system Sn–Sb is positive with a maximum of about 1.4 kJ mol−1. The enthalpies of mixing in the systems Pb–Sb, Pb–Bi, and Tl–Pb are slight negative (−0.07 to −1) kJ ml−1. The enthalpy of mixing and the ξ-function in the above given systems rule for liquid systems of B-metals.
Facile Pyrolytic Preparation of cis-Dioxoporphyrinatomolybdenum(VI) from trans-Diperoxoporphyrinatomolybdenum(VI)
Authors: Sugaya Hiroyuki , Imamura Taira
Published: July 2006

cis-Dioxo (tetraphenylporphyrinato)molybdenum(VI) [MoVI(O)2(tpp)] (tpp=5,10,15,20-tetraphenylporphyrinato) is easily prepared by the pyrolysis of the corresponding diperoxoporphyrinato complex [MoVI(O2)2(tpp)] releasing dioxygen gas at 200 °C under 10−3–10−4 Torr (1 Torr≈133.3 Pa).
Synthesis and Magnetic Property of Binuclear Oxovanadium(IV) Complex of 2,6-Diformyl-4-methylphenol Bis(benzoylhydrazone)
Authors: Sakamoto Masatomi , Itose Shoichi , Ishimori Tomitaro , Matsumoto Naohide , Okawa Hisashi , Kida Sigeo
Published: July 2006

Binuclear oxovanadium(IV) complex, [(VO)2L(OCH3)], has been synthesized, where H3L denotes 2,6-diformyl-4-methylphenol bis(benzoylhydrazone). Two metal ions are bridged by the phenolic oxygen of L3 and a methoxide oxygen. Cryomagnetic measurements (80–300 K) indicated the operation of an antiferromagnetic spin-exchange interaction (J=−191.3 cm−1) between the oxovanadium(IV) ions.
Diastereoselective Catalytic Hydrogenation of Nα-Pyruvoyl-(S)-prolinamide
Authors: Munegumi Toratane , Maruyama Tetsuya , Takasaki Michiaki , Harada Kaoru
Published: July 2006

Catalytic hydrogenation of Nα-pyruvoyl-(S)-prolinamide over palladium on charcoal in several solvents resulted in the formation of Nα-[(S)-lactoyl]-(S)-prolinamide in good d.e. up to 77%. Usefulness of N-isopropyl-(S)-prolinamide as an asymmetric moiety is described in the catalytic hydrogenation.
Piezochromism of Acridinols
Authors: Matsui Masaki , Shibata Katsuyoshi , Muramatsu Hiroshige
Published: July 2006

Piezochromic properties of acridinols and phenazinols have been examined. Only 3-acridinols showed piezochromism. This phenomenon was found to correspond to the formation of lactam isomers of the hydroxy compounds in 20 % aqueous solution of ethanol.
Terminal–Terminal Types of Liquid Crystals. I. Synthesis and Electrooptical Properties of a Ferroelectric Liquid Crystal
Authors: Shiraishi Kohei , Kato Koichi , Sugiyama Kazuo
Published: July 2006

A novel ferroelectric liquid crystal, (S)-bis(2-methylbutyl) 3,3′-[1,2-ethanediylbis[oxy-4,1-phenylenemethylidyne nitrilo-4,1-phenylene]]bis[2-propenoate] (EBOPBP) was prepared, which are composed of two chiral mesogenic groups interconnected by a very short flexible spacer chain. EBOPBP exhibts a chiral smectic C phase (Sc*). From an electrooptical effect due to a deformation of helical structure in the Sc* state, the rise time (τr) was estimated to be 240 μs at 180 °C.
Structure Analysis of Metal(I) Halides Mixed Crystal by 63Cu MAS NMR and X-Ray Diffraction Methods. I. CuxAg1−xI Crystal
Authors: Endo Kazunaka , Fujito Teruaki
Published: July 2006

63Cu MAS NMR and X-ray diffraction methods have been used to perform a structure analysis of mixed crystals, CuxAg1−xI. The mixed crystals were prepared and analyzed as a complete solid-solution and a core-shell type of crystal by the X-ray diffraction method. 63Cu signals in the complete solid-solution shifted with broadening to a high field around 14–33 ppm relative to solid CuI, as the silver/copper ratio increased. The line width of the signal was 2-to 2.5-times as broad as that for solid CuI. On the othe hand, the signal in a core-shell type of crystal did not shift much and the line width was much the same as that for CuI. The shifts and broad line widths in the complete solid-solution can be explained by considering components which involve the second-order quadrupolar coupling tensors. The quadrupolar coupling tensors are seen to be caused by changing from Td of –(CuI4)–spcies to its C3v and C2v symmetries due to replacing Cu with Ag in the crystal.
The Effect of Very High Magnetic Fields on Cyclic Voltammetry
Authors: Mogi Iwao , Kido Giyuu , Nakagawa Yasuaki
Published: July 2006

The cyclic voltammetry of ferrocene and p-benzoquinone in N,N-dimethylformamide and acetonitrile was inverstigated under very high magnetic fields up to 140 kOe (1 kOe=(1⁄4π)×103 A m−1). Plateaus of limiting currents were observed on cyclic voltammograms, and the limiting currents were remarkably enhanced by magnetic fields. These results were explained as the enhancement of mass transfer, which is caused by a magnetohydrodynamic convection. This effect was found to be pronounced at the slow potential scan rate of 10 mV s−1 in a low viscosity solvent like acetonitrile, where the current is controlled by not only mass transfer but also the electron transfer rate. The current enhancement was also observed in anodic stripping on the cyclic voltammogram of Cu2+ above 100 kOe.
Stereocontrolled Addition Reaction of Organometallics to Chiral α-Keto Amides
Authors: Fujisawa Tamotsu , Ukaji Yutaka , Funabora Makoto , Yamashita Mikio , Sato Toshio
Published: July 2006

Complementary stereoselection in the addition reaction of several organometallics to chiral benzoylformamide, prepared from benzoylformic acid and (S)-2-(methoxymethyl)pyrrolidine, could be achieved using magnesium- and titanium-based reagents to give differeent diastereomers of atrolactamide. On the other hand, the reaction of phenyl metallics to the corresponding pyruvamide afforded (S)-atrolactamide.
Channel Forming Activity of an Anionic Amphiphilic Sequential Polypeptide in a Cationic Bilayer Membrane
Authors: Higuchi Masahiro , Kinoshita Takatoshi , Takizawa Akira , Tsujita Yoshiharu , Okochi Kiyomi
Published: July 2006

A channel forming activity of hydrophobic polypeptide, hydrophobic and anionic random copolypeptide, and anionic amphiphilic sequential copolypeptide, respectively, was investigated in a cationic bilayer membrane composed of dimethyldioctadecylammonium chloride (DOACl), and correlated with their location in the membrane estimated by fluorescence spectroscopic and microscopic measurements. A pure hydrophobic polypeptide, poly(γ-methyl l-glutamate) (PMG), was incorporated into DOACl bilayer membrane resulting from their hydrophobic interaction. The incorporation, however, allowed PMG to exhibit very little channel forming activity for sodium ion. A hydrophobic and anionic random copolypeptide, composed of γ-methyl l-glutamate and l-glutamic acid containing 30 mol% of l-glutamic acid (70/30 MG/GA) could hardly penetrate the bilayer membrane and was almost localized at the cationic membrane surface because of Coulombic interaction. 70/30 MG/GA did not effectively control the sodium ion permeability through the membrane. On the other hand, an anionic amphiphilic sequential polypeptide composed of γ-methyl l-glutamate and l-glutamic acid (am. -MG/GA) was incorporated into the cationic DOACl membrane to form the transmembrane bundle ca. 40 Å in diameter. This transmembrane bundle consisting of am. -MG/GA acted as a channel for sodium ion. However, lithium ion having larger hydration size than sodium ion could not penetrate through the channel.
Asymmetric Synthesis of Fluorophenylalanines and (Trifluoromethyl)phenylalanines; the Use of Chiral Pyridoxamine-Like Pyridinophane-Zinc Complex as an Enzyme Mimic
Authors: Ando Makoto , Kuzuhara Hiroyoshi
Published: July 2006

Transamination reactions in the presence of zinc(II) ion between (R)- or (S)-15-aminomethyl-14-hydroxy-5,5-dimethyl-2,8-dithia[9](2,5)pyridinophane, pyridoxamine analog with planar chirality, and o-, m-, and p-fluorophenylpyruvic acids or o-, m-, and p-(trifluoromethyl)phenylpyruvic acids gave the corresponding fluorophenylalanines or (trifluoromethyl)phenylalanines with 33–66% enantiomeric excess in moderate yields. The observed rate constants of these transaminations, kobsd, were determined with a concomitant observation of of a linear relationship between logkobsd and Hammett’s constant, σ0.
A Novel Formation of Phenyl-Substituted Pyridines by the Reaction of N-(Diphenylphosphinyl)-1-azaallyl Anions with α,β-Unsaturated Carbonyl Compounds. A New Synthetic Equivalent of Primary Vinylamines
Authors: Kobayashi Tomoshige , Kawate Hiroshi , Kakiuchi Hidetaka , Kato Hiroshi
Published: July 2006

The N-phosphinyl-1-azaallyl anions, which were derived from the corresponding imine or enamine, reacted with α,β-unsaturated carbonyl compounds to afford phenyl-substituted pyridines along with 1-propanone and 1,5-pentanedione derivatives. A plausible mechanism involving a sequence of Michael addition and intramolecular aza-Horner-Wittig reaction is described, and the 1-azaallyl anions were found to behave as a synthetic equivalent of primary vinylamines.
Carbometallation of 1,4-Bis(trimethylsilyl)butadiyne with Trimethylaluminium Using a Bis(cyclopentadienyl)metal Dichloride Catalyst
Authors: Kusumoto Tetsuo , Nishide Kiyoharu , Hiyama Tamejiro
Published: July 2006

Carbometallation of 1,4-bis(trimethylsilyl)-1,3-butadiyne with trimethylaluminium in the presence of a bis(cyclopentadienyl)zirconium dichloride or bis(cyclopentadienyl)titanium dichloride catalyst afforded (E)-2-methyl-1,4-bis(trimethylsilyl)-1-buten-3-yne selectively after aqueous workup. Treatment of the intermediate organoaluminium compound with an electrophile like D2O, N-bromosuccinimide, N-chlorosuccinimide, or acetyl chloride gave the same hydrocarbon possessing D, Br, Cl, or CH3CO at C-1. The reaction using a bis(cyclopentadienyl)vanadium dichloride catalyst gave rise to (Z)-1,2-dimethyl-1,4-bis(trimethylsilyl)-1-buten-3-yne in a single step.
Synthesis of Binuclear Palladium(I) and (II) Complexes Containing (Benzylthiomethyl)diphenylphosphine as Bridging Ligand. The X-Ray Crystal Structure and Reactions of [Pd2Cl2(μ-PhCH2SCH2PPh2)2]
Authors: Fuchita Yoshio , Hardcastle Kenneth I , Hiraki Katsuma , Kawatani Masanori
Published: July 2006

The side-by-side type palladium(I) complex [Pd2Cl2(μ-btmp)2] (2) was synthesized either by the reaction among [PdCl2(NCMe)2], [Pd(dba)2] (dba=dibenzylideneacetone), and (benzylthiomethyl)diphenylphosphine (btmp) or by the reaction of [PdCl2(btmp-P)2] (1) and [Pd(dba)2]. The structure of 2 was established by a single-crystal X-ray diffraction study; the crystals were monoclinic, space group P21/c, with a=13.537(3), b=19.550(3), c=17.240(4) Å, β=114.59(2)°, and Z=4; final R factor 0.049 for 5490 observed reflections. The structure showed that there is a metal-metal bond [Pd–Pd 2.590(2) Å]. Treatment of 2 with sodium iodide afforded the diiodo complex [Pd2I2(μ-btmp)2], whereas that with 4-methylpyridine (4-MePy) in the presence of AgClO4 gave [Pd2(μ-btmp)2(4-MePy)2][ClO4]2. Moreover, 2 reacted with substituted acetylenes (RC≡CR′: R=Ph, R′=H; R=CO2Me, R′=H; R=R′=CO2Me) to yield A-frame type complexes [Pd2Cl2(μ-RC=CR′)(μ-btmp)2]. All the complexes obtained in this study were characterized by means of elemental analysis, and IR and NMR spectroscopy.
Synthetic Inorganic Ion-Exchange Materials. LVIII. Hydrothermal Synthesis of a New Layered Lithium Titanate and Its Alkali Ion Exchange
Authors: Sugita Mitsuru , Tsuji Masamichi , Abe Mitsuo
Published: July 2006

A new crystalline hydrous lithium titanate, (Li1.81, H0.19)Ti2O5·2.2H2O, was synthesized hydrothermally at 190 °C by a reaction of hydrous titanium dioxide with LiOH solution. The compound has a layered structure and showed a C–base-centered orthorhombic system with the lattice constants, ao=16.66±0.02 Å, bo=3.797±0.002 Å, and co=3.007±0.003 Å. The lattice constants were changed to ao=18.08±0.03 Å, bo=3.784±0.003 Å, and co=2.998±0.002 Å upon conversion to the hydrogen form. The 8.5% increase in the ao value along the a axis suggests a layered structure. A hypothetical structure was proposed. The H+ form showed the ion-exchange selectivity at an ionic strength of 0.1 in the order of K+<Na+6 and Li+<K+<Na+ at pH<6.
The Effects of the Reaction Variables on the Yields of Acrylic Acid and Methyl Acrylate in the Reaction of Acetic Acid with Methanol in the Presence of Oxygen
Authors: Ai Mamoru
Published: July 2006

The effects of the reaction variables on the yields of the aldol condensation products, i.e., acrylic acid and methyl acrylate, in the reaction of acetic acid with methanol in the presence of gaseous oxygen was studied using a V–Ti–P ternary oxide catalyst with an atomic ratio of 1:2:6, respectively. The best catalyst performance was obtained with an oxygen/methanol molar ratio of between 0.5 to 0.75. The yield of acrylic acid decreased with increasing the methanol concentration, while that of methyl acrylate increased; the sum of the two yields increased with methanol concentration above 360°C. The feed rate did not have much effect on the yield, except at high conversions. Better catalytic performance was observed with longer contact times at lower temperatures than with shorter contact times at higher temperatures.
Preparation and Characterization of Cobalt(III)-Dimethyldithiocarbamato Complexes Containing R2P(CH2)nPR2 (R=CH3, C6H5; n=1,2,3,4) and PR3 (R=C2H5, C6H5). Crystal Structure of [Co{(CH3)2NCS2}{(CH3)2PCH2P(CH3)2}2](BF4)2
Authors: Kita Masakazu , Okuyama Akiyoshi , Kashiwabara Kazuo , Fujita Junnosuke
Published: July 2006

Twelve new cobalt(III)-phosphine complexes, [Co(dtc)x{(CH3)2P(CH2)nP(CH3)}2}3−x](3−x)+ (x=1, 2; n=1,2,3), [Co(dtc)2{(C6H5)2P(CH2)nP(C6H5)2}]+ (n=1,2,3,4), and trans-[Co(dtc)2(PR3)2]+ (R=C2H5, C6H5) were prepared, where dtc denotes dimethyldithiocarbamate(1–). The molecular structure of [Co(dtc){(CH3)2PCH2P(CH3)2}2](BF4)2 was determined by X-ray analysis. Crystal data are: monoclinic, space group Cc, a=15.927(4), b=11.726(2), c=14.422(7) Å, β=91.38(3)°, V=2692.6(15) Å3, Z=4, R=0.058 for 2251 reflections. The complex ion forms a distorted octahedron with the small P–Co–P (73.1(2) and 75.5(2)°) and S–Co–S (75.97(9)°) chelate angles. The mean Co–P and Co–S distances are 2.238(5) and 2.285(3) Å, respectively. On the basis of the angular overlap model(AOM) treatment, the ligand field bands were assigned and the effect of ring size of diphosphine chelates on these bands were examined. Positive eπ(P) values were necessary to satisfy the observed data, and the result indicates that the Co-dπ orbitals are destabilized by coordination of the phosphine ligand.
Systematic Enumeration of High Symmetry Molecules by Means of Unit Subduced Cycle Indices with and without Chirality Fittingness
Authors: Fujita Shinsaku
Published: July 2006

A novel method of enumerating isomers is presented by using adamantane as a parent skeleton. This method is based on unit subduced cycle indices with and without chirality fittingness, the indices being derived from the subduction of coset representations. The chirality fittingness, which is determined by examining the relationship between a point group and its subgroup, controls the mode of substitution by achiral and chiral substituents. The method provides detailed enumerations concerning symmetries and molecular formulas, whereas Pólya’s theorem takes only the latter into consideration.