Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 51 , Issue 10
Showing 1-50 articles out of 85 articles from the selected issue
  • Takuya Yamashita, Akira Shibata, Shinsuke Yamashita
    1978 Volume 51 Issue 10 Pages 2751-2756
    Published: 1978
    Released: April 19, 2006
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    The interaction of polypeptide (benzyloxycarbonyl derivatives of basic poly(γ-amino acid), benzyl esters of acidic poly(α-amino acid), and poly(L-leucine)) and lipid (fatty acids, fatty alcohols and cholesterol) at the air–water interface was investigated. From the additivity rule of mean molecular areas and the work of collapse of the monolayers, it was found that the characteristic interaction occurs in the polymer rich region (less than 0.2 lipid mol fraction), and that the interaction is stronger for the polymer with higher helical content. The interaction was found to take place between side chains of polypeptides and lipids, and to be mainly of hydrophobic nature. The components in mixed polypeptide–cholesterol monolayers exhibit characteristic miscibilities depending upon the chemical composition of polymer side chains. The polarized infrared spectra of collapsed films consisting of single or mixed components indicate that the polymer component is aligned in a direction parallel to the compressing barrier.
  • Akira Shibata, Shinsuke Yamashita, Takuya Yamashita
    1978 Volume 51 Issue 10 Pages 2757-2761
    Published: 1978
    Released: April 19, 2006
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    The effect of water structure on the interaction of synthetic polypeptides with fatty acids in monolayers at the air-water interface was investigated. It was found that SCN, F, and urea exert a remarkable effect upon the hydrophobic interaction in monolayers. SCN and urea disrupt the hydrated structure biult up around the hydrocarbon moieties of polypeptides and lipids at the interface. On the other hand, the presence of F as a structure maker tends to stabilize the hydrophobic bonding. The infrared spectra of polymer components were practically identical for the collapsed films in the absence and presence of SCN, F, and urea.
  • Masaaki Ogasawara, Larry Kevan
    1978 Volume 51 Issue 10 Pages 2762-2764
    Published: 1978
    Released: April 19, 2006
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    N,N,N′,N′-Tetramethyl-p-phenylenediamine (TMPD) fluorescence lifetimes in 2-methyltetrahydrofuran (MTHF) glass at 77 K (13.5 ns) and in ethanol glass at 77 K (12.3 ns) and 4 K (11.5 ns) were measured using 347 nm excitation from a frequency doubled ruby laser. Trapped electrons and TMPD+ were generated in these matrices by photoionization and the recombination fluorescence stimulated by 694 nm laser light was found, within an experimental limit of 1 ns, to occur with the same lifetime as the directly excited fluorescence. A convolution analysis indicates that the electron-cation recombination lifetimes are ≤1 ns in all these matrices at the temperatures given. It is also suggested that a lower limit for the electron mobility of 0.005 cm2 V−1 s−1 is implied by these data.
  • Masakazu Iwamoto, Yukihiro Yoda, Noboru Yamazoe, Tetsuro Seiyama
    1978 Volume 51 Issue 10 Pages 2765-2770
    Published: 1978
    Released: April 19, 2006
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    Formation and reactivity of oxygen adsorbates on the surface of α-Fe2O3 were investigated in the temperature range 0–600 °C by means of a temperature programmed desorption (TPD) technique. At least four different states of adsorbed oxygen were indicated by four TPD peaks, the maxima of which appeared at 50–300 (α), 350–360 (β), 480–490 (γ), and >600 °C (δ), respectively. Mode of preparation hardly affected the essential nature of oxygen adsorption (or desorption) except the relative amounts of respective desorptions. Of these adsorbates, α, whose desorption peak shifts over a wide temperature range depending upon adsorption conditions, was interpreted to be molecular oxygen (O2 or O2) bonded to the oxide surface with an extraordinarily broad heterogeneity, while β and γ species were tentatively assigned to O2 and O, respectively, adsorbed on different sites. The activation energies of desorption were 23.8 and 54.6 kcal/mol for β and γ, respectively. On exposure to gaseous hydrogen, β species as well as α turned more reactive than γ, though γ was also reactive at higher temperatures. The reaction of β and α species with hydrogen at lower temperatures gave rise to an increase in γ adsorption. This is accounted for by assuming a reaction in which the molecular adsorbates (α and β) react with hydrogen to leave the atomic adsorbates (γ) behind.
  • Akira Kuboyama
    1978 Volume 51 Issue 10 Pages 2771-2775
    Published: 1978
    Released: April 19, 2006
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    The phosphorescence spectra of 1,4-naphthoquinone (NQ), 2-methyl-, 2,6-dimethyl-, 2,6-diisopropyl-, and 2,6-di-t-butyl-NQ’s in various kinds of solutions at 77 K were studied. The phosphorescence bands of NQ and 2,6-di-t-butyl-NQ in all the solutions and those of the other NQ’s in saturated hydrocarbon solutions are assigned to the n,π* band. In the ethanol solution, 2-methyl-NQ shows a dual phosphorescence, the lifetimes of which are different and which depends on the excitation wavelength. In the Daifloil solutions, 2-methyl- and 2,6-dimethyl-NQ’s also show a dual phosphorescence. In the toluene solutions, these two NQ’s show remarkably broad phosphorescence bands. These facts are discussed on the basis of the electronic structures at the excited states of these NQ’s.
  • Masao Nakamura, Shinichi Takeuchi
    1978 Volume 51 Issue 10 Pages 2776-2780
    Published: 1978
    Released: April 19, 2006
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    The relaxations were observed after suddenly dilating or compressing the equilibrium surfaces of aqueous solutions of poly(oxyethylene) dodecyl ethers, C12H25(OC2H4)nOH (n= 5 and 7), at 303 K. The relaxation is expressed as the Maxwell model, with a Hookean surface-area modulus and a Newtonian surface-area viscosity, if the absolute value of an area strain is less than 0.3. The surface-area modulus is dependent upon the amount of surfactant molecules adsorbed in the surface, Γ, regardless of the sign of the area strain. The relaxation time, τc, in the case of compression is dependent on Γ, and τd in the case of dilation depends on the monodispersed concentration of the surfactant in the bulk solution, C. The surface dilational viscosity, ηbA, has a maximum around the concentration at which the surface reaches the saturated adsorption. The rate constants for the adsorption and desorption were estimated by determining empirically the functions of 1/τd and 1/τc with respect to C and Γ respectively.
  • Akira Fujimoto, Kozo Inuzuka
    1978 Volume 51 Issue 10 Pages 2781-2785
    Published: 1978
    Released: April 19, 2006
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    The hydrogen bond between 4-amino-5H-[1]benzopyrano[3,4-c]-pyridin-5-one (benzopyranopyridine) derivatives including their related compounds (pyridine, aniline, and coumarin) and alcohols (methanol and ethanol) is discussed experimentally in detail. The formation of a hydrogen bond between the nitrogen atom of the benzopyranopyridine ring and the hydroxyl group of methanol was investigated by IR spectral measurements. The equilibrium constants for the formation of hydrogen-bonded 1 : 1 complexes were determined from the UV spectral data. The enthalpy changes accompanying complex formation were obtained from a knowledge of the temperature dependence of the equilibrium constants. The values of the enthalpy changes range approximately from 4.5 to 5.2 kcal/mol in the benzopyranopyridine–ethanol systems. It may be concluded that the hydrogen bond of the benzopyranopyridine–ethanol system occurs mainly at the nitrogen atom of benzopyranopyridine ring, because the thermodynamic properties for hydrogen bond formation between benzopyranopyridine and ethanol showed a striking resemblance to those of the pyridine–ethanol system. In addition, the presence of an intramolecular hydrogen bond between the amino and carbonyl groups of benzopyranopyridine derivatives was confirmed by means of IR spectra.
  • Kozo Inuzuka, Akira Fujimoto
    1978 Volume 51 Issue 10 Pages 2786-2790
    Published: 1978
    Released: April 19, 2006
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    In a previous paper the experimental considerations on the hydrogen bonding between benzopyranopyridine derivatives including related compounds (pyridine, coumarin, and aniline) and alcohols were made, and the thermodynamic constants for the formation of the hydrogen-bonded complexes were obtained from UV spectroscopic studies. In this paper the molecular orbital calculation by the CNDO/2 method was conducted to further clarify the experimental results. Several conclusions were drawn from the present calculation: (1) Benzopyranopyridine has an intramolecular hydrogen bond between its amino and carbonyl groups. (2) The hydrogen bond energy of 2-alkyl benzopyranopyridines with alcohol is larger than that of the 1-alkyl compounds. (3) Benzopyranopyridine has four positions for hydrogen bond formation with alcohol, that is, the ring nitrogen atom, the carbonyl group, the ring oxygen atom, and the amino group. The ring nitrogen atom gave rise to the largest hydrogen bond energy among the four positions. Therefore, the corresponding hydrogen-bonded complex plays an important role in the benzopyranopyridine–alcohol system. (4) The hydrogen bond energy depended on the charge density of the atom which gave rise to the hydrogen bond with alcohol. Especially, substitution of the electron donating group such as amino and methyl groups at the position which increases the charge density of the atom giving rise to a hydrogen bond with alcohol increases the hydrogen bond energy.
  • Akira Yamauchi, Takuma Kunisaki, Toshiaki Minematsu, Yukiko Tomokiyo, ...
    1978 Volume 51 Issue 10 Pages 2791-2794
    Published: 1978
    Released: April 19, 2006
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    Liquid membrane electrodes selective to alkyl sulfate ions were devised for octyl, decyl, and dodecyl sulfate ions, and employed in the study of micellar solutions. A nitrobenzene solution of hexadecyltrimethylammonium—alkyl sulfate complex was used as the liquid membrane. The membrane potential-logarithmic concentration showed a maximum at the critical micelle concentration (CMC), an increase with the Nernstian slope at the lower concentrations and a decrease at the higher concentrations. Below CMC, the presence of excess inorganic salt did not alter the Nernstian slope, i.e., the liquid membrane was more highly permselective to alkyl sulfate ions than to inorganic anions. From a simple thermodynamic consideration of a micellar solution based on the pseudo phase model of the micelle, the change in the activity of alkyl sulfate ions and the dissociation of the micelle were discussed. It has been deduced that the concentration of the singly dispersed surfactant ions above CMC is reduced with concentration, except for the presence of a large excess of added electrolyte, and that the degree of dissociation of the micelle is unaltered even when the excess electrolyte is added.
  • Shinichi Nagata, Tokio Yamabe, Kenichi Fukui
    1978 Volume 51 Issue 10 Pages 2795-2799
    Published: 1978
    Released: April 19, 2006
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    The electronic structure of the H2S anion radical has been investigated by means of the non-empirical unrestricted Hartree-Fock method. The most stable conformation of this radical has been obtained at bond length R(S–H)=1.550 Å and bond angle θ (<HSH)=160°. These values are relatively larger in comparison with observed values of the neutral molecule (R=1.335 Å and θ=92.2°). ESR hyperfine coupling constants and excitation energies have also been examined through analyses of the electronic structure of the most stable conformation of this radical. Furthermore, the dissociation process, H2S→H2+S or HS+H, has been discussed.
  • Norihiro Matubayasi, Kinsi Motomura, Makoto Aratono, Ryohei Matuura
    1978 Volume 51 Issue 10 Pages 2800-2803
    Published: 1978
    Released: April 19, 2006
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    The interfacial tension α between water and hexane solution of 1-octadecanol has been measured as functions of temperature T, pressure p, and mole fraction of 1-octadecanol in hexane x10 by the pendant drop method. The curves of γ vs. T, γ vs. p, and γ vs. x10 show noticeable break points. Calculated thermodynamic quantities such as energy changes, entropy changes, and volume changes associated with the adsorption show the points of discontinuity at a certain temperature, pressure, and composition, corresponding to the above breaking points. It has been clarified that the first order phase transition between the expanded and condensed states takes place at the interface like that of monomolecular films spread on water surfaces. The expanded state is characterized by a relatively high energy, high entropy, and large volume, while the condensed state by low energy, low entropy, and small volume.
  • Kiyoshi Ichimura, Nobuo Nakamura, Hideaki Chihara
    1978 Volume 51 Issue 10 Pages 2804-2806
    Published: 1978
    Released: April 19, 2006
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    35Cl nuclear quadrupole resonance frequencies have been measured in powders of β-chlorocrotonic acid, and β-chloroisocrotonic acid to be 34.966 and 34.261 MHz, respectively, at 78 K. Zeeman effect experiments were conducted on a single crystal of β-chloroisocrotonic acid and the asymmetry parameter of the electric field gradient has been determined to be 0.174±0.016 at 78 K. The π-electron density on the chlorine site has been estimated from the asymmetry parameter according to Bersohn and discussed on the basis of the semi-empirical Pariser-Parr-Pople molecular orbital treatment.
  • Katsutoshi Ohkubo, Ikuhiro Terada, Kohji Yoshinaga
    1978 Volume 51 Issue 10 Pages 2807-2812
    Published: 1978
    Released: April 19, 2006
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    The asymmetric dehydrogenation of racemic alcohols by an effective Ru2Cl4((−)-diop)3 (diop=2,3-O-isopropylidene-1,4-bis(diphenylphosphino)butane) was investigated with and without unsaturated hydrogen acceptors at 120–195 °C, with particular reference to the enantioselective factors and the reaction mechanism. The magnitude of enantioselectivity was substantially affected by the structures of the alcohols and of the hydrogen acceptors and by the reaction temperature; the hydrogen acceptors (R1CH=CHR2: R1\ eweqH and R2\ eweqH) contributed to the enhancement of the selectivity through the newly formed asymmetric centers which result from their coordination to the chiral Ru(II) complex. The activation parameters (ΔH\ eweq and ΔS\ eweq) obtained from the linear Arrhenius dependence of the rate constants of each enantiomer (R- or S-alcohol) established an isokinetic relationship, and the defference in the parameters of the each enantiomer (ΔΔH\ eweq and ΔΔS\ eweq) also showed a satisfactorily linear correlationship between them. It is deduced from the present study that the enantioselection of R- and S-alcohols occurs at different coordination distances toward the chiral Ru(II) complex between the enantiomers under asymmetric circumstances.
  • Tamotsu Inabe, Yoshio Matsunaga
    1978 Volume 51 Issue 10 Pages 2813-2816
    Published: 1978
    Released: April 19, 2006
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    The electrical resistivity of the 5,6 : 11,12-bis(epidithio)naphthacene(TTT)–iodine system was examined using poly crystalline compactions. The room-temperature resistivity reaches a minimum of 0.3 ohm cm at the composition of the well-studied metallic phase, TTT–I1.5, and a shoulder as large as 200 ohm cm occurs at the composition of the other metallic phase, TTT–I2.7. The apparent activation energy for semiconduction at the latter composition is as much as 0.13 eV, indicating some semiconductor behavior in directions other than the needle axis. The appearance of the latter phase is also manifested by a drastic increase in the Seebeck coefficient near this composition, which corresponds to a change in the amount of charge per TTT molecule from 0.68 to 0.85. The diffuse reflection spectra were recorded for TTT–I1.53 and TTT–I2.79. The resemblance between the spectrum of the iodine-rich complex and that of TTT–Br is noted.
  • Takashi Tamaki
    1978 Volume 51 Issue 10 Pages 2817-2821
    Published: 1978
    Released: April 19, 2006
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    The absorption and emission spectra of 1- and 2-aroyl- and acetylanthracenes were measured in various solvents. The emission spectra moved to longer wavelengths and their forms changed from the structured ones to the structureless ones with increasing solvent polarity, while the absorption spectra showed no appreciable changes under the same conditions. These emissive features became more distinguished with increasing electronwithdrawing ability of the aroyl group. The dipole moments of the fluorescent state as estimated from the Lippert-Mataga formula were 7–16 D for these compounds. The assignments of the low-lying excited states are described in terms of the electronic transitions of the parent anthracene, 1La and 1Lb, which undergo perturbation by the substitution.
  • Hiroki Imoto, Kazuo Ueno, Nobuatsu Watanabe
    1978 Volume 51 Issue 10 Pages 2822-2825
    Published: 1978
    Released: April 19, 2006
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    The decomposition reaction of the graphite fluoride film formed on the edge plane of pyrolytic graphite, carbon, and graphite electrodes was faster in a KF·HF bath (250 °C) than in a KF·2HF bath (100 °C) due to the higher temperature of KF·HF bath. The critical current densities (CCD’s) were about 0.1 A/cm2 for the layer and edge planes of pyrolytic graphite, carbon, and graphite electrodes in the KF·HF bath, and the CCD for each electrode was larger in the KF·HF bath than in the KF·2HF bath. The anode effect took place easily on the glassy carbon electrode in the KF·2HF bath. However, the anode effect did not take place in liquid hydrogen fluoride due to its very low surface tension, although the graphite fluoride film was formed on the electrode surface. The zeta-potential of aluminum fluoride particles in liquid hydrogen fluoride containing 0–20 mol of potassium fluoride/1 and that of magnesium fluoride particles in liquid hydrogen fluoride were almost zero at 0 °C. From the results it is not proper that the effect of the addition of dispersed particles upon the anode effect is explained by the view of electrostatic force of the particles proposed so far.
  • Koichiro Miyajima, Hiromitsu Yoshida, Masayuki Nakagaki
    1978 Volume 51 Issue 10 Pages 2826-2832
    Published: 1978
    Released: April 19, 2006
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    Osmotic and activity coefficients have been determined by the isopiestic comparison method on the water–guanidinium bromide–tetrabutylammonium bromide system at 25 °C. The values of the excess free energy change of mixing and the interaction parameter g0 on Friedman’s formalism were large and negative in magnitude. These results have been discussed in terms of the mixed ion pairing and structural change of water.
  • Hiroshi Sato, Koichi Itoh, Hiroaki Takahashi
    1978 Volume 51 Issue 10 Pages 2833-2835
    Published: 1978
    Released: April 19, 2006
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    A new multiple transmission method of time domain spectroscopy was developed. A small amount of the sample (0.6 cm3) is needed in this measurement. The dielectric dispersion and absorption curves of 1-propanol, 1-butanol, and 1-pentanol have been obtained as recorder traces of the spectra stored in the minicomputer. Three dielectric parameters, ε, ε0, and τ, are estimated for these alcohols.
  • Norio Murase, Teruyuki Fujita, Naotake Morikawa, Shozo Koga
    1978 Volume 51 Issue 10 Pages 2836-2837
    Published: 1978
    Released: April 19, 2006
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    Proton diffusion in the α-phase of polycrystalline 1-hexadecanol was studied using C16H33O3H and C15H3114CH2OH. It was found that hydroxyl proton diffuses translationally more easily than the whole molecule. A value of (7±5)×10−7 cm2/s was obtained for the diffusion coefficient of the hydroxyl proton in the α-phase. This fast diffusion is ascribed to the presence of molecular rotation involving hydrogen-bond networks in the α-phase of the crystal. Since the mechanism for the proton diffusion seems to be the same as that for the protonic conduction in this α-phase, proton mobility can be calculated from the diffusion coefficient, assuming that molecular rotation makes the rate determining step in both processes.
  • Akihiko Matsumoto, Rei Yugeta, Hidetoshi Karasawa, Shin Sato
    1978 Volume 51 Issue 10 Pages 2838-2840
    Published: 1978
    Released: April 19, 2006
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    The γ-radiolyses of liquid nitrogen solutions of nitrogen oxide and of oxygen gave nitrogen dioxide and ozone, respectively, as the main products. Over the solute concentrations from 0.01 to 0.1 mol l−1, the G-values of both products were constants: G(NO2)=3.3 and G(O3)≈7. The G-value of nitrogen dioxide in the former solution probably corresponds to the G-value of nitrogen atoms from liquid nitrogen. For the formation of ozone in the latter solution, a possible reaction mechanism is discussed. Dinitrogen oxide was found as a minor product, the G-value being about 0.1 for both solutions.
  • Takao Itoh, Hiroaki Baba, Takeshi Takemura
    1978 Volume 51 Issue 10 Pages 2841-2846
    Published: 1978
    Released: April 19, 2006
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    The phosphorescence quantum yields of benzaldehyde, acetophenone, p-fluorobenzaldehyde, p-chlorobenzal-dehyde, and benzophenone vapors, measured at low pressure down to the order of 10−3 Torr as a function of excitation wavelength, are essentially constant in the region of excitation energy corresponding to the S1(n, π*) state, whereas the yields decrease very sharply as the excitation energy is raised to the value corresponding to the S2(π, π*) state. This indicates that the nonradiative pathway in the carbonyl compound varies according to the type of the singlet state to which the molecule is initially excited. When excited to the S1 and S2 states, the molecule passes to the phosphorescent triplet state and a decomposing state, respectively. Two mechanisms are suggested and examined for understanding the nonradiative properties of the carbonyl compound vapors: (I) The internal conversion S2→S1 is slow compared with the conversion from S2 to the decomposing state; (II) the vibrational energy redistribution in S1 between the vibrational mode populated through S2→S1 and the mode to be populated optically is slow compared with the conversion from the former mode to the decomposing state.
  • Tadaaki Kakutani, Yoshikazu Morihiro, Mitsugi Senda, Reiji Takahashi, ...
    1978 Volume 51 Issue 10 Pages 2847-2854
    Published: 1978
    Released: April 19, 2006
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    The standard redox potentials of five R/R+ redox couples that can be considered as candidates for the reference redox couple, i.e., the anion/cation couples of tris(2,2′-bipyridine)iron(II), tris(2,2′-bipyridine)ruthenium(II), cobaltocene, perylene, and 9,10-diphenylanthracene, have been determined in acetonitrile, dimethyl sulfoxide, N,N-dimethylformamide and propylene carbonate by means of polarography and voltammetry. The results confirmed that the standard potentials of these redox couples are independent of the solvents studied so that they can be used as solvent-independent reference points for potential comparisons. The solvent activity coefficients of the silver ion have been estimated on the basis of these reference redox couples.
  • Harumasa Sugino, Isao Tanaka, Tamaichi Ashida
    1978 Volume 51 Issue 10 Pages 2855-2861
    Published: 1978
    Released: April 19, 2006
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    The molecular structures of N-(benzyloxycarbonyl)prolylleucine ethyl ester and N-(t-butoxycarbonyl)prolylleucine benzyl ester, were determined by the X-ray method. The former belongs to the orthorhombic system P212121 with Z=4, a=9.917(3), b=21.960(3), and c=9.956(1) Å; the latter belongs to the monoclinic system P21 with Z=2, a=10.475(1), b=17.910(1), c=6.303(1) Å, and β=90.213(7)°. Both structures were determined by the direct method; the final R indexes are 0.062 for the former and 0.072 for the latter. An extended conformation found in both dipeptides shows that in terms of the Pro–Leu unit alone this conformation is preferable to the folded β-turn conformation such as is found in longer peptides. The leucyl side chain conformations found in peptides or amino acids were also studied. For the residues occurring in the peptides the C′–Cα–Cβ–Cγ–Cδ1 transzigzag conformation was found overwhelmingly, without any obvious relationships to the main chain torsion angles. On the other hand, for the C-termini leucyl residues and leucines the N–Cα–Cβ–Cγ–Cδ2 trans-zigzag conformation was rather preferred and the ψ values were restricted to a narrow range.
  • Hisaharu Hayashi, Saburo Nagakura
    1978 Volume 51 Issue 10 Pages 2862-2866
    Published: 1978
    Released: April 19, 2006
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    External magnetic field effects on chemical reactions in solution are studied theoretically and consequently reactions through radical pairs are shown to be controlled by a magnetic field. Some conditions necessary for the occurrence of the magnetic field effects are discussed, the effects being classified into three types: (1) the electronic Zeeman effect (ΔgβH), (2) the hyperfine interaction effect, and (3) the mixed effect.
  • Ryoichi Nakagaki, Saburo Nagakura, Takayoshi Kobayasm, Suehiro Iwata
    1978 Volume 51 Issue 10 Pages 2867-2872
    Published: 1978
    Released: April 19, 2006
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    The Sn←S0 and Sn←S1 transition bands were measured with m- and p-dimethylaminoacetophenones and related compounds in order to clarify the characters of the excited singlet states. The observed spectra were reasonably interpreted by the use of the theoretical results based on the composite molecule method. The longest wavelength band (S1←S0) of the meta isomer has mainly the local excitation (LE) character of aniline (1B21A1), while that of the para isomer is ragarded as the intramolecular charge-transfer band. In the para isomer the LE transition corresponding to 1B21A1 is covered by the intense CT band. The Sn←S1 transitions of the meta isomer are almost of LE character, whereas those of the para isomer are of back CT nature. This is mainly attributed to the difference in the character of S1.
  • Hisao Kawamura
    1978 Volume 51 Issue 10 Pages 2873-2878
    Published: 1978
    Released: April 19, 2006
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    The interference effects of calcium on barium in atomic absorption spectroscopy, i.e., background absorption and noise effect having been attributed to the CaOH green band were further studied. The behavior of the interfering calcium hydroxide radical and the barium atom itself was studied in relation to the distribution of natural species, OH and CN, using conventional and nitrogen-shielded nitrous oxide–acetylene flames. A remarkable reduction in the calcium interference was demonstrated using a nitrogen-shielded version of moderately fuel-rich flames. This effect was attributed to the suppression of CaOH formation which was brought about by an improvement in the reducing nature of the flame with shielding.
  • Hisanobu Wakita
    1978 Volume 51 Issue 10 Pages 2879-2881
    Published: 1978
    Released: April 19, 2006
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    Hydrated rare earth carbonate single crystals were obtained in metasilicate gels. The formulas of the crystals were determined to be (RE)2(CO3)3·8H2O (RE=La, Pr) and (RE)2(CO3)3·4.54H2O (RE=Nd), and the crystal structures were determined to be of the lanthanit type.
  • Hiroshi Kawazoe, Masaru Nishino, Hideo Hosono, Kei Isozaki, Kazuo Amet ...
    1978 Volume 51 Issue 10 Pages 2882-2885
    Published: 1978
    Released: April 19, 2006
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    Radical formation was found in the thermal dehydration-condensation process of hydrated hydrogenorthophosphates (HHP). It was considered that the intermediate radical reacted with lattice defects, thus resulting in the generation of trapped electrons. The gray coloration and the ESR sensitivity of the heated HHP were assigned to the formation of the trapped electron.
  • Hiroshi Kawazoe, Kazuo Ametani, Masahiko Imai, Takafumi Kanazawa
    1978 Volume 51 Issue 10 Pages 2886-2889
    Published: 1978
    Released: April 19, 2006
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    On the thermal reaction of H3PO4 or NH4H2PO4 with metal salts, such as Na2CO3 or Mg(OH)2, the “overcondensation” of the phosphate anions and the conjugate formation of metal oxide were observed. The “overcondensation” was defined as a formation reaction of the phosphate with a larger polymerization degree than that of the product to be expected from the [MO or M2O]/[P2O5] mole ratio of the starting mixtures. The “overcondensed” tetrametaphosphate and the conjugate oxide, magnesium oxide, were detected on the thermal condensation of MgHPO4·3H2O and of a mixture of NH4H2PO4 or H3PO4 and Mg(OH)2. The “overcondensed” tripoly- and trimeta-phosphate were found in the course of the formation reaction of Na pyrophosphate from a mixture of Na2CO3 and NH4H2PO4.
  • Yoshiyuki Hirashima, Yasuhiro Yamamoto, Shigeru Takagi, Taisuke Amano, ...
    1978 Volume 51 Issue 10 Pages 2890-2893
    Published: 1978
    Released: April 19, 2006
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    Di(2-ethylhexyl) phosphoric acid+ (D2EHPA or HX) extracts lanthanoids (Ln) from a moderately acidic solution by cation exchange reaction: Ln3++m(HX)n\ ightleftarrowsLnX3·3HX+3H+. From the mode of extraction m is estimated to be 3 in benzene diluent, and smaller than 3 in heptane diluent. The change of the relative extractability with the atomic number of lanthanoids is in line with what is expected from the concept of the tetrad effect proposed by Peppard et al. When the hydrogen ion concentration is very high, the main reaction is solvation: Ln3++3A+q(HX)n\ ightleftarrowsLnA3·4HX. In benzene diluent q is 2 and n is 2, while q is 1.6–1.7 in heptane diluent. It can be attributed to the difference in the association degree of D2EHPA that m or q is smaller in heptane than in benzene.
  • Yoshihisa Yamamoto
    1978 Volume 51 Issue 10 Pages 2894-2897
    Published: 1978
    Released: April 19, 2006
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    The 1H-NMR spectrum of the 5-nitrosalicylatotetraamminecobalt(IV) complex did not show the signals of phenyl protons of the salicylato ligand, but did show those of ammine protons at 3.7 (s, 6H) and 3.3 ppm (s, 6H). The 13C-NMR peaks could not be observed because of the paramagnetism. The 1H-NMR spectra of the salicylatotetraamminecobalt(III) complexes showed peaks at 3.96 (s, 6H), 3.65 (s, 3H), and 3.38 ppm (s, 3H) for the ammine protons and at 6.7–8.1 ppm (m, 4H) for the phenyl protons of the salicylato ligand. Their 13C-NMR spectra showed seven signals for the salicylato ligand. The IR peaks assignable to the rocking deformation vibration were observed at 830–855 cm−1 for the ammine ligands of 5-nitrosalicylatotetraamminecobalt(IV) complexes and at 820–840 cm−1 for those of salicylatotetraamminecobalt(III) complexes, in conformity with the view that the former complexes are actually cobalt(III) complexes of a free radical nature.
  • Yoshiaki Ito, Akira Terada, Shinichi Kawaguchi
    1978 Volume 51 Issue 10 Pages 2898-2904
    Published: 1978
    Released: April 19, 2006
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    Substitution reactions of the trans-CoSO3 (H2O or OH) (en or tn)2 complex with Cl, Br, CH3COO, N3, NO2, NCS, CN, and SO32− have been studied by the spectrophotometric method. The equilibrium constant of anation KH2OX spans many orders of magnitude, e.g. from 1.24 for bromide to 1.23×107 M−1 for cyanide in the case of the en complex, and is correlated to the electron donor constant En which was defined by Edwards. The kinetics of the substitution reactions is adequately interpreted by virtue of the reversible D mechanism via a five-coordinate intermediate CoSO3(AA)2+. Release of the ligand Xn from trans-CoSO3(X)(tn)2(1−n)+ proceeds 10–25 times faster than from the corresponding bis(ethylenediamine) complex, and the kinetic ring-size effect is attributed to the larger stability of the en complex as compared with the tn complex at the ground state.
  • Kosuke Izutsu, Toshio Nakamura, Taiji Murayama, Taitiro Fujinaga
    1978 Volume 51 Issue 10 Pages 2905-2908
    Published: 1978
    Released: April 19, 2006
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    As a part of potentiometric studies of the complexing of univalent cations in acetonitrile with other solvents by the use of a cation-sensitive glass electrode, investigations were carried out of the complexing of the ammonium ion in acetonitrile with such solvents as water, methanol, N-methylformamide, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, 1-methyl-2-pyrrolidone, and hexamethylphosphoric triamide, and also with dibenzo-18-crown-6. Prior to the study of the complexing, the cation-sensitive glass electrode was confirmed to respond in a Nernstian way to the change in the ammonium-ion activity which occurs due to the change of the solvent (solvent effect). The ammonium ion in acetonitrile formed complexes of mono- and di-solvated species with methanol and water. Formations of up to tri-solvated species were formed with DMF, DMA, and DMSO, and up to tetra-solvated species with 1-methyl-2-pyrrolidone and NMF. With HMPA, even penta-solvated species were formed. The complex formation constants of the mono-solvated ammonium ion, β1 (mol −1 dm3), were 1.7 with methanol, 5.6 with DMF, 14 with DMSO, 17 with DMA, 31 with 1-methyl-2-pyrrolidone, 3.0×102 with NMF, and 1.2×103 with HMPA. The association constant of ammonium perchlorate in acetonitrile was determined conductometrically to be 25 mol −1 dm3.
  • Minoru Kubota, Akio Yamamoto
    1978 Volume 51 Issue 10 Pages 2909-2915
    Published: 1978
    Released: April 19, 2006
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    A variety of new alkoxocopper and phenoxocopper(I) complexes containing triphenylphosphine ligands have been prepared by the reactions of methylbis(triphenylphosphine)copper(I) etherate (I) with the corresponding alcohols and phenols. The isolated complexes were characterized by elemental analysis, IR and NMR spectroscopy and chemical reactions. The reactions of the alkoxocopper and phenoxocopper complexes with alkyl halides and acyl halides or carboxylic anhydrides yield ethers and carboxylic esters, respectively. The stoichiometric exchange reactions of the alkoxo group in the alkoxocopper complexes with carboxylic esters proceed smoothly and the alkoxocopper complexes were found to act as excellent catalysts for the transesterifications between carboxylic esters and alcohols. The exchange reactions take place also between the alkoxocopper complexes and phenols or thiols producing phenoxocopper or alkylthiocopper complexes with the liberation of alcohols. Amides and nitromethane react with the alkoxocopper complexes releasing alcohols to give N-bonded amidocopper and O-bonded acinitrocopper complexes, respectively. The thermolysis of the alkoxocopper complexes in various solvents were studied and the mechanism and the factors influencing the course of thermolysis discussed.
  • Hiroko Wada, Kazuyoshi Ikuta, Genkichi Nakagawa
    1978 Volume 51 Issue 10 Pages 2916-2919
    Published: 1978
    Released: April 19, 2006
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    Formation constants of mixed ligand complexes of copper(II)-1-(2-pyridylazo)-2-naphthol chelate (Cu(pan)) with bidentate ligands, which accelerate the rate of color change of 1-(2-pyridylazo)-2-naphthol (PAN) indicator in copper(II)-EDTA titrations, were determined by the spectrophotometric method in 5 or 10% v/v dioxane–H2O at μ=0.1 (KNO3) and at 25 °C. The overall formation constants (logKCu(pan)Lpan.L=log ([Cu(pan)L]/[Cu][L][pan]) are 21.26 (5% dioxane) for 2,2′-bipyridine, 21.64 (10% dioxane) for ethylenediamine, 22.80 (5% dioxane) for 8-hydroxy-5-quinolinesulfonic acid, 19.39 (10% dioxane) for glycine, and 20.68 (10% dioxane) for iminodiacetic acid. These ligands coordinate with Cu(pan) chelate as bidentate ligands, and the mixed ligand complexes may have a distorted octahedron structure. Thus the Cu–pan bond in the mixed ligand complex is weakened.
  • Masahiro Mikuriya, Hisashi Okawa, Siego Kida, Ikuhiko Ueda
    1978 Volume 51 Issue 10 Pages 2920-2923
    Published: 1978
    Released: April 19, 2006
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    The crystal structure of hetero-metal binuclear complex, CuCo(fsaen)·3H2O, with N,N′-bis(3-carboxysalicylidene)ethylenediamine (H4fsaen) was determined by the single-crystal X-ray diffraction method. The crystals are trigonal, space group P3221, a=b=12.845(2), c=9.962(1) Å, V=1423.5(4) Å3, and Z=3. The structure was solved by the heavy atom method and refined by the block-diagonal least-squares method to an R factor of 0.028. The copper atom is coordinated by two nitrogen atoms and two phenolic oxygen atoms in a square-planar manner. The cobalt atom is coordinated by two equatorial carboxyl oxygen atoms, two equatorial phenolic oxygen atoms and two axial water oxygen atoms in a distorted octahedral geometry. The detailed structure determined is in conformity with the magnetic and spectral properties previously reported.
  • Tetsuro Majima, Yoshikane Kawasaki
    1978 Volume 51 Issue 10 Pages 2924-2927
    Published: 1978
    Released: April 19, 2006
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    From measurements of the molecular weights, dimethyllead(IV) complexes with ONO tridentate Schiff-base ligands, 2-(2-oxidobenzylideneamino)phenolatos, were found to have dimeric six-coordinate structure in CHCl3, in which either one of the two oxygen atoms in the ligands bridges the lead atoms. The 2J(207Pb–CH3) values increase and the δ(Pb–CH3) values shift to a higher magnetic field with an increase in the donor strength of the solvents. Linear relationships between the 2J(207Pb–CH3) and δ(Pb–CH3) values and Hammett’s σ values of the substituents on the Schiff-base ligands were obtained. These results suggest that the complexes form monomerically as a result of coordination with one and/or two solvent molecules in such donor solvents as DMSO and HMPA, and that the 2J(207Pb–CH3) values is dependent mainly on the change in the positive charge on the lead atom: the change in the mean excitation energy, ΔE, in the Fermi contact term.
  • Kiyoshi Tamura, Shoji Harada, Michinori Hiraissh, Tatsuya Yasunaga
    1978 Volume 51 Issue 10 Pages 2928-2931
    Published: 1978
    Released: April 19, 2006
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    An ultrasonic absorption study has been carried out on aqueous acidic solutions of mercury(II) acetate. The absorption data shows a single-relaxation phenomenon in the frequency range of 15–95 MHz. On the other hand, the results of the pH measurement indicate that the only mecury(II) acetate complexes conceivable in solution are of the HgL+ and HgL2 forms (L denotes the acetate ion); the succesive formation constants of these complexes, together with the mercury(II) hydrolysis constants, are also determined. The equilibrium constants reported are: 2.1×103 for K1, 4.9×103 for K2, 6×10−4 for Kh1, and 1.0×10−3 for Kh2, at 30 °C and I=1. On the basis of the above results, the ultrasonic relaxation absorption is ascribed to the complex formation reaction: HgL++L\leftrightharpoonsHgL2. The rate constants and the volume change of this reaction are determined to be: kfo=7.8×109 M−1 s−1, kbo=1.6×106 s−1, and ΔV=18 cm3 mol−1, at 30 °C.
  • Hidenori Shibuya, Hitoshi Watarai, Nobuo Suzuki
    1978 Volume 51 Issue 10 Pages 2932-2936
    Published: 1978
    Released: April 19, 2006
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    The solution behavior of thenoyltrifluoroacetone (TTA) has been investigated in a series of higher alcohols which are often used in solvent extraction by means of UV and NMR spectrometries. It was experimentally confirmed that TTA exists in the enol and hemiacetal forms in dehydrated alcohol, while in wet alcohol we should also take a hydrate form into consideration. The fractions of the species at equilibrium were determined, and their dependencies on the water concentration and on the solvent properties, i.e., the dielectric constant and the solubility parameter, were examined. The interconversion rate between the enol and hemiacetal forms were also observed as a function of the water concentration.
  • Toshio Yao, Yoichi Taniguchi, Tamotsu Wasa, Soichiro Musha
    1978 Volume 51 Issue 10 Pages 2937-2941
    Published: 1978
    Released: April 19, 2006
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    The voltammetric oxidation of hypoxanthine, xanthine, and uric acid was investigated by means of linearsweep voltammetry, cyclic voltammetry, and controlled-potential coulometry. Hypoxanthine, xanthine, and uric acid each gave a single oxidation peak at a different potential, with a stationary glassy carbon electrode, over the wide pH range of 0–13. Hypoxanthine was initially oxidized in a two-electron step to xanthine, which was then further oxidized in a two-electron step to uric acid, as well as the enzymatic oxidation. All three substances were strongly adsorbed on the surface of the glassy carbon electrode, so that the concentration vs .anodic peak current curves were not linear. The adsorption on the electrode was very dependent on the pH, and especially at pH values around neutrality the anodic peaks were ill-defined. However, in such acid solutions as H3PO4 and H2SO4, the voltammetric oxidation was a diffusion-controlled process and the differences between the peak potentials were most pronounced (ca. 400 mV). Consequently, it was possible to determine simultaneously three hydroxypurine bases by using 1 M H2SO4 or 1 M H3PO4 as a supporting electrolyte, without prior treatment or separation procedures.
  • Ryokichi Tsuchiya, Akira Uehara, Kazuhiko Noji, Hitoshi Yamamura
    1978 Volume 51 Issue 10 Pages 2942-2945
    Published: 1978
    Released: April 19, 2006
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    Heating of a mixture of CrCl3·6H2O and triethylenetetramine (trien) produced violet products which gave cis-α-[Cr2(OH)2trien2]X4·2H2O and cis-α-[Cr(OH)(H2O)trien]X2·H2O (X=Cl, Br or I) on treatment with aqueous NaX solutions. cis-α-[CrCl2trien]Cl·2H2O were obtained in the presence of a trace amount of water. Absolutely dry conditions are necessary for the preparation of cis-β-[CrCl2trien]Cl. The thermally induced reversible cis-α↔cis-β isomerization was detected in the complexes cis-α-[Cr(OH)(H2O)trien]Cl2·H2O and cis-β-[CrCl2-trien]Cl by means of derivatography and high-temperature IR spectroscopy. The former cis-α-hydroxoaqua complex was found to be converted irreversibly into cis-β-form above 225 °C in the solid-phase. The cis-β-form obtained readily isomerized to cis-α-form in aqueous media. The dimeric cis-α-[Cr2(OH)2trien2]4+ was converted gradually into the monomeric cis-α-[Cr(OH)(H2O)trien]2+ in water.
  • Katsuhiko Miyoshi, Chang Eon Oh, Hiroshi Nakazawa, Hayami Yoneda
    1978 Volume 51 Issue 10 Pages 2946-2950
    Published: 1978
    Released: April 19, 2006
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    The induced circular dichroism (ICD) spectra were measured in the first d-d transition region for the following cobalt(III)–amine complexes in aqueous solutions of (R,R)-tartrate and (R,R)-tartratoantimonate(III) anions; [Co(en)n(NH3)6−2n]3+ (n=0–3) and cis-[Co(en)2(RNH2)2]3+ (R=methyl and ethyl). It was found that a single negative CD band was induced for all the complexes in (R,R)-tartrate solution, while a single positive one was induced for most of them in (R,R)-tartratoantimonate(III) solution; the ICD developed in it was composed of a single negative band for [Co(en)3]3+ and of two bands with opposite sign for trans-[Co(en)2(NH3)2]3+ and cis-[Co(en)2(EtNH2)2]3+. The ICD spectra obtained for racemic complexes were interpreted in terms of differential interactions of Λ- and Δ-enantiomers with (R,R)-tartrate or (R,R)-tartratoantimonate(III), and an attempt was made to correlate the sign of their ICD spectra with their chromatographic behavior on an SP-Sephadex ion-exchanger with these chiral anions as an eluent.
  • Tadashi Hara, Kaoru Fujinaga, Katsuya Tsuji
    1978 Volume 51 Issue 10 Pages 2951-2956
    Published: 1978
    Released: April 19, 2006
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    Simultaneous determination of the atomic ratio between C, H, O, and N in a metallo-organic compound containing transition element is possible by the pyrolytic sulfurization gas chromatographic method, addition of reducing agent being unnecessary. Analytical results of metallo-organic compounds depend on the characteristics of their metal oxides. A few organophosphorus compounds were analyzed. The formation of water could be predicted from the atomic ratio of carbon to oxygen in a compound.
  • Seiichiro Ogawa, Yuji Hongo, Hitoshi Fujimori, Keiji Iwata, Akira Kasu ...
    1978 Volume 51 Issue 10 Pages 2957-2963
    Published: 1978
    Released: April 19, 2006
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    Chlorination of four aminocyclitol and six inositol derivatives with sulfuryl chloride gave the chloro substitution products, which were then dechlorinated by hydrogenolysis with Raney nickel or by treatment with tributyltin(IV) hydride giving the corresponding deoxy compounds. Several useful aminocyclitols, including 2,4-dideoxy- and 2,4,5-trideoxystreptamines, were prepared from 2-deoxystreptamine derivatives by these procedures.
  • Jun Niwa
    1978 Volume 51 Issue 10 Pages 2964-2969
    Published: 1978
    Released: April 19, 2006
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    The contributions to 13C shifts from the diamagnetic term of the neighboring carbon atom and from the “ring-current” have been estimated by means of the equations given in a previous paper (J. Niwa, Bull. Chem. Soc. Jpn., 48, 118 (1975)). A semi-empirical expression has been derived for the substituent-induced 13C chemical shift in an aromatic side chain by considering such contributions in addition to the local diamagnetic and paramagnetic terms of the carbon atom in question. The applicability of the expression has been examined for α-carbons of 4-substituted derivatives of styrenes and α-methylstyrenes, and for 1′-carbons of 4-substituted biphenyls.
  • Mutsuji Sakai, Sh\={u}ji Nishikawa, Haruo Koike, Yasumasa Sakakibara, ...
    1978 Volume 51 Issue 10 Pages 2970-2972
    Published: 1978
    Released: April 19, 2006
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    Dimethyl methylenesuccinate, dimethyl citraconate, and dimethyl mesaconate mutually rearranged in the presence of triethylamine at room temperature. The rearrangement was found dependent on the polarity of the solvent and the basicity of the amine, and the rate was found to be first-order in both ester and amine. A mechanism has been proposed from a kinetic study.
  • Michio Kondo
    1978 Volume 51 Issue 10 Pages 2973-2975
    Published: 1978
    Released: April 19, 2006
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    It has been found, from the 1H NMR spectra that two esters exist in an intramolecularly hydrogen bonded form (Z) in CDCl3 and DMSO solutions. Two amides, on the other hand, have been found to exist as a mixture of the Z and E isomers in DMSO solutions. H/D exchange at the olefinic site has been found to occur by the addition of D2O to the DMSO solutions of the amides, but not in the cases of the esters. The amide configurations are discussed. An interpretation of the 13C NMR spectra of these compounds is also given.
  • Tsutomu Nonaka, Mitsuo Asai
    1978 Volume 51 Issue 10 Pages 2976-2982
    Published: 1978
    Released: April 19, 2006
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    The electrolytic reductions of several 1-acyl-8-benzoylnaphthalenes were carried out by means of controlled potential electrolysis at a mercury cathode in various catholytes. The isomeric ratio of the cis- and trans-1,2-acenaphthenediols thus formed depended on the kind of acyl group, supporting electrolyte, organic solvent in the catholyte, and cathode potential applied. The mechanism of the reductive cyclization is discussed from the stereochemical point of view, and it is proposed that the cyclization may occur not only by the intramolecular coupling of the biradical intermediate, but also by the intramolecular nucleophilic addition of the anionic part of the carbanion intermediate to its unreacted carbonyl group.
  • Noboru Torimoto, Tadao Shingaki, Toshikazu Nagai
    1978 Volume 51 Issue 10 Pages 2983-2987
    Published: 1978
    Released: April 19, 2006
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    The reactions of N,N-dichlorourethane (1) with substrates, such as hydrocarbons and ethers, gave N-substituted urethanes (3) and urethane (4) in the presence of copper or copper(I) chloride. The reactions with aromatic hydrocarbons and cyclic ethers possessing an alkyl group at the α-position, however, gave no azepine and no alkoxyurethane respectively, in contrast to those of ethoxycarbonylnitrene generated from the azide. The reactions with the tertiary C–H bonds of cis- and trans-1,4-dimethylcyclohexanes proceeded non-stereospecifically, contrary to those of the nitrene. The reactions with alcohols led to high yields of 4, accompanied by the corresponding aldehydes, but afforded no O–H insertion product. The addition of a radical inhibitor, nitrobenzene, reduced the yield of 3, while it had no appreciable effect on the yield of 4. Furthermore, the reactions of N-chlorourethane with hydrocarbons also gave 3 and 4. These results suggest that the reaction of 1 with substrates proceeds not by a nitrene mechanism, but by a metal-radical mechanism.
  • Akio Iwama, Toshihiro Toyoda, Misaku Yoshida, Tetsuo Otsubo, Yoshiteru ...
    1978 Volume 51 Issue 10 Pages 2988-2994
    Published: 1978
    Released: April 19, 2006
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    A series of layered cyclophanes where an anthracene ring is stacked in different modes with the same or other π-systems has been synthesized by the Hofmann elimination method or photodesulfurization for studying the transannular π-electronic interaction. Photochemical and thermal interconversions have been observed between syn-(1,4)anthracenophane and its isomer and have been discussed with reference to the X-ray crystal data. From the electronic spectra it has been established that the transannular interaction increases with overlapping between the two faced aromatic rings and that when the overlap between the two chromophores is the same, the interaction increases relative to the dimension of the faced chromophore.
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