Bulletin of the Chemical Society of Japan
Online ISSN : 1348-0634
Print ISSN : 0009-2673
ISSN-L : 0009-2673
Volume 48 , Issue 2
Showing 1-50 articles out of 95 articles from the selected issue
  • Katsuhiro Tamura, Tatsuya Imoto
    1975 Volume 48 Issue 2 Pages 369-374
    Published: 1975
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    The ET-value was determined for eight solvents at 25 °C over the pressure range 1–1,960 kg/cm2. They increase with pressure; the pressure dependence is affected by the nature of the solvents. It was also found that there is a linear relationship between the pressure coefficient of ET and that of the logarithm of the rate constant of a Menschutkin reaction: In k=a+bET On the basis of this relationship, an equation was derived in which the volume of activation ΔV\ eweq is represented by the pressure coefficient of ET; the effect of solvents on ΔV\ eweq is discussed by making use of this equation.
  • Kazuaki Harata, Hisashi Uedaira
    1975 Volume 48 Issue 2 Pages 375-378
    Published: 1975
    Released: March 27, 2006
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    The circular dichroism spectra of β-cyclodextrin complexes with naphthalene derivatives were investigated. A remarkable difference in the spectra was observed between the 1-substituted naphthalene complex and the 2-substituted naphthalene complex, indicating that the steric effect of substituents on the formation of the complex is so strong that the structures may be different for these complexes. The calculation of the rotational strength by the method of Kirkwood-Tinoco revealed that the structure of the 2-substituted naphthalene complex is an axial inclusion.
  • Masaharu Oguni, Takasuke Matsuo, Hiroshi Suga, Syûzô Seki
    1975 Volume 48 Issue 2 Pages 379-391
    Published: 1975
    Released: March 27, 2006
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    Phase transitions of K4Fe(CN)6·3H2O and its deuterate were studied through the measurements of differential thermal analysis curves, heat capacity, volume expansion and Raman spectra. Samples prepared by recrystallization from the aqueous solution were found to be in the metastable phase. The ferroelectric transition temperature between two stable monoclinic phases was determined to be 247.8 K and 252.7 K for the hydrate and deuterate, respectively. The enthalpy and entropy changes of the transition were estimated to be 2592 J mol−1 and 12.41 JK−1 mol−1, respectively, for the hydrate, and 3017 J mol−1 and 14.36 JK−1 mol−1, respectively, for the deuterate. The molecular mechanism of the transition was discussed in terms of entropy change. The transition was also concluded to be of the second order according to Ehrenfest’s criterion. Irreversible transformation of tetragonal to monoclinic phase was observed for the first time for the deuterate as a new type of phase change having a Martensitic nature. These irreversible transformations took place in the temperature region covering 20 K below ca. 232 K and ca. 237 K for the hydrate and deuterate, respectively. The anhydrous salt showed no transformation in the temperature region between 13 K and room temperature.
  • Tsutomu Okuda, Koji Yamada, Yoshihiro Furukawa, Hisao Negita
    1975 Volume 48 Issue 2 Pages 392-395
    Published: 1975
    Released: March 27, 2006
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    The nuclear quadrupole resonances (NQR) due to 35Cl and 81Br in TeCl4 and TeBr4 have been observed and their Zeeman effects have been examined. Each spectrum consists of six resonance lines with equal intensities, which are assigned to the two species of TeCl3+ ions or TeBr3+ ions. The asymmetry parameter of the electric-field gradient is, at most, 5% in each case. The relative orientation among the zero-splitting patterns of six resonance lines is consistent with the crystal structure of TeCl4, which consists of the tetramers of (TeCl3+Cl-)4, as was recently determined by X-ray diffraction analysis. The zero-splitting patterns of the TeBr4 crystal are so similar to those of TeCl4 that the former crystal seems likely to consist of tetramers of (TeBr3+Br-)4 as well. The average ∠X–Te–X bond angles in TeX3+ ions were found to be 95.9° for the chloride and 96.7° for the bromide. The values for the chloride are in good agreement with those obtained by the X-ray analysis. On the other hand, the bond character of the TeX3+ ions in TeX4AlX3 (X=C1, Br) was compared with that of TeX4 from NQR.
  • Noboru Furusho, Tsuyoshi Komatsu, Tsurutaro Nakagawa
    1975 Volume 48 Issue 2 Pages 396-402
    Published: 1975
    Released: March 27, 2006
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    The torsional braid analysis (TBA), thermogravimetry, and IR spectroscopy of polymethacrylates, polyacrylate, poly(vinyl alcohol), and their related polymers were carried out in air. The chemorheological properties of these polymers are markedly dependent on their chemical structures. First, the α-hydrogen atom plays an important role. In poly(methyl acrylate), the chemorheological behavior is similar to that of the polymers which have tendency to crosslink, whereas poly(methyl methacrylate) does not show any such behavior. A similar situation was found when comparing poly(acrylic acid) with poly(methacrylic acid). At the same time, the influence of the functional groups was examined. Second, the change in the mechanical properties due to crosslinking becomes more noticeable with an increase in the side-chain length of the methacrylate polymers. Furthermore, in addition to procedures used in the previous work, a new method of kinetic analysis of the heating-rate dependence was carried out in the case of poly(acrylic acid). The apparent activation energies estimated by this treatment are in good agreement with those estimated by other procedures.
  • Yoji Hara, Ichimin Shirotani, Yukako Ohashi, Katsuyuki Asaumi, Shigeru ...
    1975 Volume 48 Issue 2 Pages 403-407
    Published: 1975
    Released: March 27, 2006
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    The absorption and luminescence spectra of the polycrystalline magnesium, barium, and potassium salts of tetracyano platinate (II) were measured at hydrostatic pressures up to 5.4 kbar. These three salts showed an anomalously large red shift with pressure in both the absorption and luminescence spectra. The X-ray powder diffraction measurement was carried out for the magnesium salt up to 70 kbar. At 70 kbar the Pt–Pt distance decreased from 3.16 Å to 2.93 Å, 7.3% in linear compressibility. In the low pressure region up to ∼20 kbar, the Pt–Pt distance was observed to decrease greatly. The intramolecular transition 5dz2→6pz energy was calculated as a function of the Pt–Pt distance. By comparing the calculated and observed values, such a large red shift in the absorption spectra was tentatively explained in terms of electrostatic stabilization of the intramolecular transition 5dz2→6pz due to the decrease of the intermolecular distance and due to the consequent increase of the 5dz2→6pz intermolecular CT character.
  • Toshiko Seimiya, Mary E. Purchase
    1975 Volume 48 Issue 2 Pages 408-411
    Published: 1975
    Released: March 27, 2006
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    The minute amount of hydrophobic substances 10−8∼10−7 mol/cm2 (geometric area) on cotton fabric surface can effectively be detected by fluorescent probe using magnesium-8-anilino-1-naphthalenesulfonate (ANS). The cotton fabrics were dyed in aqueous ANS solution (1×10−4 mol/1), before and after the staining with stearic acid, palmitic acid, tristearin, oleic acid, and squalene, and the intensities of fluorescence from the cotton surface was measured by reflectance spectrophotometer under the varying wavelength of ultra-violet (200–300 mμ). The intensity of fluorescence increased with the increase of fatty stain on the surface, but showed the tendency of saturation by exceeding the closest packing of the fatty acid monolayers. Correlation was also found between the fluorescent intensity and the yellowness (b-value) of naturally soiled cotton fabrics. The bleaching of the yellowed fabrics by sodium hypochlorite effectively reduced the b- value but did not change the fluorescence appreciably, and suggested that the hydrophobic substances still remained on the fabric surfaces in spite of their white appearance.
  • Tsunetoshi Kobayashi, Katsuyuki Yokota, Saburo Nagakura
    1975 Volume 48 Issue 2 Pages 412-415
    Published: 1975
    Released: March 27, 2006
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    The photoelectron spectra of cis- and trans-stilbenes, fumaric acid, dimethyl maleate, and dimethyl fumarate were measured and interpreted, special attention being paid upon their difference between the corresponding trans- and cis-isomers. The two characteristics were found for the photoelectron spectra of cis- and trans-stilbenes: (1) the splitting between the first and fifth bands is smaller for the cis-isomer (steric-hindrance effect); (2) the splitting between the second and third bands is larger for the cis-isomer (through-space interaction). The difference in the carbonyl n orbital ionization potentials between dimethyl maleate and fumarate was interpreted in terms of through-bond interaction.
  • Toyoharu Hayashi, Noboru Mataga, Yoshiteru Sakata, Soichi Misumi
    1975 Volume 48 Issue 2 Pages 416-419
    Published: 1975
    Released: March 27, 2006
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    ESR spectra of anion radicals of some triptycene and [2.2]paracyclophane derivatives were observed and analyzed in order to study the delocalization interactions between composite aromatic rings.
  • Hiroshi Morita, Satoru Matsumoto, Saburo Nagakura
    1975 Volume 48 Issue 2 Pages 420-423
    Published: 1975
    Released: March 27, 2006
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    Triplet-triplet (T–T) absorption bands were observed at 300, 297, and 320 nm for m- and p-dicyanobenzenes, and 1,3,5-tricyanobenzene, respectively. The nature of the observed spectra was investigated by calculating the wave functions of the triplet states and by analyzing them by the configuration analysis method. It was concluded that the T–T absorption bands of m- and p-dicyanobenzenes, and 1,3,5-tricyanobenzene correspond essentially to the transition from the locally (within the benzene ring) excited state to the intramolecular charge-transfer state.
  • Genkichi Nakagawa, Hiroko Wada, Tomohiko Hayakawa
    1975 Volume 48 Issue 2 Pages 424-427
    Published: 1975
    Released: March 27, 2006
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    In the determination of stability constants of metal complexes, usually the measurements of the activities of free metal ions at very low levels are required. The electrode response of an Orion Model 94–29 copper(II) ion selective electrode at very low activity levels was studied in the various metal buffers composed of copper(II) ions and an excess of ligand. Usually the linear calibration range of the copper(II) ion selective electrode was extended to very low activity levels in the presence of a strong complexing agent. The stability constants of copper(II) complexes with acetate, ammonia, ethylenediamine, glycine, iminodiacetic acid, 1,10-phenanthroline, etc. were determined successfully. In the cases of EDTA and NTA, however, the lower limit of the linear calibration range was abnormally high and the stability constant of copper–EDTA or –NTA chelate could not be obtained. Some experimental results on the potentiometric titration of copper(II) ion with EDTA were also presented.
  • Jun-ichiro Mizusaki, Kazuo Fueki, Takashi Mukaibo
    1975 Volume 48 Issue 2 Pages 428-431
    Published: 1975
    Released: March 27, 2006
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    Using an electrochemical cell, Ag/AgX (X=Br or I)/C, the steady-state chemical potential profiles of silver in AgX were determined under d-c polarization conditions. Several Pt probes were attached to the AgX specimens, and the potential differences between the Ag electrode and the Pt probes were measured. It was found that, in order to obtain the correct chemical potential profiles, the Pt probes must be embedded in the specimen to avoid influences of the degradation of AgX at the surface of the specimen. The results obtained by the cell with carefully assembled probes revealed that Wagner’s theory holds for AgX.
  • Mitsuru Tanaka, Shoji Kaneshina, Seiji Kuramoto, Ryohei Matuura
    1975 Volume 48 Issue 2 Pages 432-434
    Published: 1975
    Released: March 27, 2006
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    The critical micelle concentrations (CMC) of dodecyltrimethylammonium bromide (DTAB) in aqueous urea solutions have been determined over a range of pressures up to 2500 atm at 25 and 35 °C. The partial molal volumes of DTAB in micellar (\barVm) and singly-dispersed states (\barVs) have also been determined in aqueous urea solutions at 25 °C. \barVs increases with the addition of urea, while \barVm remains approximately constant. The partial molal entropy change of micellization (Δ\barSm) in water increases with an increase in the pressure up to about 1500 atm, while Δ\barSm in 3-m urea solution remains virtually unaltered in the low-pressure region. The results suggest that the “iceberg” structure of water around the hydrocarbon chain of the monomeric surfactant is effectively broken down by urea.
  • Toshio Yao, S\={o}ichir\={o} Musha
    1975 Volume 48 Issue 2 Pages 435-438
    Published: 1975
    Released: March 27, 2006
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    The polarographic behavior of orotic acid at the dropping mercury electrode was studied in the Britton-Robinson buffer solution; it was found to be a complex function of the pH. Three polarographic waves were observed over the pH range from 2 to 12. In the 1M HClO4 electrolyte, orotic acid showed a very well-defined, diffusion-controlled, two-electron polarographic reduction wave which enabled us to determine orotic acid polarographically. A polarographic method for the determination of orotic acid in milk was proposed, and the effect of the presence of surface-active substances like proteins was investigated. The proposed method is very simple and rapid, and permits the accurate determination of 4–1000 μg/g of orotic acid in milk.
  • Kenzo Nagase, Katsuya Sato, Nobuyuki Tanaka
    1975 Volume 48 Issue 2 Pages 439-442
    Published: 1975
    Released: March 27, 2006
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    The thermal dehydration and decomposition of the oxalates of Mg(II), Ca(II), Sr(II), Ba(II), Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) were investigated by means of TG, DTA, DSC, EGA, X-ray powder diffraction analysis, and reflectance and infrared spectroscopies. In general, the temperature at which the oxalates were dehydrated increased with 1/r, where r denotes the radius of metal ion. The heats of dehydration (ΔHH2O) of the alkaline earth metal oxalates increased with 1/r, but those of transition metal oxalates decreased as 1/r increased. By considering the decomposition products, the reactions of anhydrous oxalates were classified into three groups and the relations between the decomposition temperatures and 1/r were discussed for each group.
  • Toshio Ishiyama
    1975 Volume 48 Issue 2 Pages 443-447
    Published: 1975
    Released: March 27, 2006
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    The geometrical isomers, cis-dichlovo-trans-(methanol) (hydroquinone) (2,2′-bipyridine)ruthenium(II) and cis-dichlovo-cis-(methanol)(hydroquinone)(2,2′-bipyridine)ruthenium(II), [RuCl2(MeOH)(QH2)bipy] (complex I and II), were synthesized by reduction and substitution reactions of [RuO4bipy] and [RuO2(OH)2bipy] with hydroquinone in hydrochloric acid solution, and methanol. cis-Chloro(hydroquinonato)bis(2,2′-bipyridine)-ruthenium(II), cis-[RuCl(QH)(bipy)2], was obtained from the substitution reaction of complex I or II with 2,2′-bipyridine in methanol, and cis-chloro(hydroquinone)bis(2,2′-bipyridine)ruthenium(II) chloride, cis-[RuCl(QH2)-(bipy)2]Cl, was also obtained from the substitution of cis-trans-[RuCl2(MeOH)(QH2)bipy] in methanol containing hydrochloric acid. cis-Dihydroxobis(2,2′-bipyridine)ruthenium(II),cis-[Ru(OH)2(bipy)2], was obtained by heating an aqueous solution of cis-[RuCl (QH) (bipy) 2]. Trihydroxoaquo (1,10-phenanthroline) ruthenium (III), [Ru(OH)3(H2O)phen] was also synthesized from [RuO3phen]2O and [Ru(OH)3phen]2O by reduction reactions similar to those used for [RuCl2(MeOH)(QH2)bipy]. These complexes were characterized by the infrared, visible and ultraviolet absorption spectra, and also by polarographic and magnetic measurements. The structures are discussed.
  • Hiroshi Kobayashi, Ken Eguchi, Youkoh Kaizu
    1975 Volume 48 Issue 2 Pages 448-453
    Published: 1975
    Released: March 27, 2006
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    Magnetic circular dichroism (MCD) was observed in the region of the 22000 cm−1 band of [Cr(CN)5NO]3−. The absorption band was assigned to a charge-transfer transition linearly polarized in the direction of Cr–NO, while the MCD observed in the same region was assigned to B term extrema of the (d, d*) transitions hidden beneath the charge-transfer band. The charge-transfer transition gives rise to an absorption peak but no MCD, since the transition is polarized in the direction of the orbital angular momentum, even in the case where a degenerate excited state is involved.
  • Takaji Yasui
    1975 Volume 48 Issue 2 Pages 454-457
    Published: 1975
    Released: March 27, 2006
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    Fourteen complexes of the type [Co(aa)2phen]X and [Co(aa)2dipy]X (where aa is the anion of glycine, β-alanine, L-serine, or L-proline) were newly prepared. Two geometrical isomers (trans(N) and cis(O)cis(N)) for the glycinato and β-alaninato complexes, four geometrical and/or diastereomeric isomers ((+)D- and (−)D-trans(N) and -cis(O)cis(N)) for the L-serinato complexes, and two diastereomers ((+)D- and (−)D-trans(N)) for the L-prolinato complex were separated. These complexes were characterized by absorption, circular dichroism spectra, and 1H and 13C NMR spectra. The absolute configurations of the L-serinato and L-prolinato complexes were assigned as Λ and Δ for the (+)D- and (−)D- isomers, respectively.
  • Nobuko Matsuoka, Jinsai Hidaka, Yoichi Shimura
    1975 Volume 48 Issue 2 Pages 458-464
    Published: 1975
    Released: March 27, 2006
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    Three isomers of cis(O)-bis(L-alaninato)ethylenediaminecobalt(III) perchlorate, four isomers of potassium cis(N)-bis(L-alaninato)oxalatocobaltate(III) and two isomers of potassium trans(N)-bis(L-prolinato)oxalatocobaltate(III) have been prepared, and their configurations have been assigned by absorption and circular dichroism spectra. From analysis of the circular dichroism spectra of about 25 complexes of these types (the aminoacidato ligands are glycinato, L-alaninato, L-serinato and L-prolinato), the configurational and the vicinal circular dichroism curves have been separated and discussed. The vicinal circular dichroism curve shows a pattern characteristic of the absolute configuration of α-aminoacidato ligand and of the geometrical structure of the complex.
  • Hiroshi Kobayashi, Badri Vishal Agarwala, Youkoh Kaizu
    1975 Volume 48 Issue 2 Pages 465-468
    Published: 1975
    Released: March 27, 2006
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    Magnetic circular dichroism (MCD) of cis-dicyanobis(2,2′-bipyridine) iron(II) was measured for a variety of solvents. The visible absorption band is assigned to the lowest “iron(II) to bipyridine” charge-transfer transition. The complex exhibits a significant MCD in its lowest charge-transfer absorption band. The transition shows a shift to higher wave number with an increase in the proton-donating power of solvent. This spectral shift is attributed to hydrogen-bonding interactions of protolytic solvent molecules. In H2SO4 this dibasic complex is subjected to stepwise protonations. The complex is diamagnetic in protolytic solvents, and even in cone H2SO4 the diprotonated complex formed is mostly present in the diamagnetic state.
  • Takashi Okamura, Kunio Ohzeki, Tomihito Kambara
    1975 Volume 48 Issue 2 Pages 469-471
    Published: 1975
    Released: March 27, 2006
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    It was found that the cupric ions fixed on the resin are removed by acetylacetone(Hacac) to form bisacetylacetonatocopper(II), Cu(acac)2. By the addition of a small amount of pyridine-water mixture to the copper-(II) form resin in acetylacetone milieu, the cupric ions are quantitatively removed from the resin in the form of pyridine adduct, and the pyridinium ions are adsorbed on to the resin in place of the cupric ions. The reaction was successfully applied to the synthesis of Cu(acac)2.
  • Fujio Mizukami
    1975 Volume 48 Issue 2 Pages 472-475
    Published: 1975
    Released: March 27, 2006
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    The syntheses, resolution and structure of three oxalato complexes of cobalt(III) with tetramine ligand, R(4), R(6)- and R(4), S(6)-4,6-dimethyl-1,9-nonanediamine (RR- and RS-2,3″, 2-tet), and R(6), S(8)-6,8-dimethyl-2,5,9,12-tetraazatridecane (N,N′-Me2-RS-2,3″,2-tet) are reported. Only one geometrical isomer (cisβ) was isolated for each complex, [Co(ox)(N,N′-Me2-RS-2,3,″,2-tet)]+, [Co(ox)RS-2,3″,2-tet]+ and [Co(ox)RR-2,3″,2-tet]+· The central six-membered chelate rings of (−)546-cis β-[Co(ox)(N,N′-Me2-RS-2,3″,2-tet]+ and (−)546-cis β-[Co(ox)(RS-2,3″,2-tet)]+ take a chair conformation with two equatorial methyl groups, and that of (−)546-cis β-[Co-(ox)(RR-2,3″,2-tet)]+ a chair conformation with an axial and equatorial methyl group.
  • Masaru Saeki, Naoki Toshima, Hidefumi Hirai
    1975 Volume 48 Issue 2 Pages 476-479
    Published: 1975
    Released: March 27, 2006
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    The alkyl hydrogens of N-(2-alkyldiphenylmethylene)acetamides were found to be readily replaced with deuterium on irradiation in deuteriomethanol (CH3OD). It is proposed that the deuteration proceeds via an enamide isomer produced by intramolecular hydrogen transfer from the o-alkyl group to the excited C=N double bond. An intermolecular hydrogen atom abstraction pathway was excluded because neither N-(4-methyldiphenylmethylene)acetamide in deuteriomethanol(CH3OD) nor diphenylmethane in deuteriomethanol(CH3OD) in the presence of N-(diphenylmethylene)acetamide was deuterated. Intramolecular hydrogen abstraction is essential for the deuteration, because no deuteration occurs on irradiation of 2-methylbenzophenone semicarbazone which undergoes no photoreduction. The difference in reactivities of the ortho-substituted imines between in solution and in a rigid matrix is discussed from the viewpoint of syn-anti isomerization.
  • Tetsuo Hiraoka, Takeo Kobayashi
    1975 Volume 48 Issue 2 Pages 480-483
    Published: 1975
    Released: March 27, 2006
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    Phenylsulfene (II) generated from benzylsulfonyl chloride (I) and triethylamine, reacted with N-(p-Substituted)-benzylidene-methylamine to give 2-methyl-4-phenyl-3-(p-substituted-phenyl)-1,2-thiazetidine 1,1-dioxide whose cis and trans isomers were separated. Both cis and trans 3,4-diphenyl-2-methyl-1,2-thiazetidine 1,1-dioxide (IV and V) afforded trans stilbene and benzaldehyde on pyrolysis. This new fragmentation reaction could be explained by a stepwise decomposition because of its non-stereospecificity.
  • Yoshiki Okamoto, Toshihiro Okada, Hiroshi Sakurai
    1975 Volume 48 Issue 2 Pages 484-487
    Published: 1975
    Released: March 27, 2006
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    In addition to phosphonyl dichlorides, a significant amount of phosphoryl dichlorides was obtained by the reaction of propyl and allyl halides with phosphorus trichloride in oxygen atmosphere. Formation of the P–O–C bond can be explained by a scheme involving a preferential reaction of the bridged intermediate radical with oxygen.
  • Takaaki Horaguchi, Takahachi Shimizu
    1975 Volume 48 Issue 2 Pages 488-490
    Published: 1975
    Released: March 27, 2006
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    3-Hydroxy-5-methoxyphenanthro[4,5-bcd]furan (Ia) was synthesized by the dehydrogenation of 5-methoxy-3-oxo-1,2,3,8,9,9a-hexahydrophenanthro(4,5-bcd)furan (IVa), starting from 8-hydroxy-7-methoxy-1-tetralone (IIb).
  • Tadashi Masamune, Mitsunori Ono, Hajime Matsue
    1975 Volume 48 Issue 2 Pages 491-496
    Published: 1975
    Released: March 27, 2006
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    Nine 5-alkyl- and 5-aryl-2-furoic acids were reduced under controlled Birch conditions and then esterified with acidic methanol. 2-Furoic acids with 5-alkyl groups gave good yields of methyl 5-alkyl-2,5-dihydro-2-furoates, which were obtained as mixtures of cis- and trans-diastereoisomers. These 2,5-dihydrofuroates revealed interesting spectroscopic properties; (1) large long-range coupling constants, 5–7 and 3–4 Hz, between protons at C2 and C5 were observed in the NMR spectra of cis- and trans-diastereoisomers, respectively, and (2) two high absorption maxima due to the ester carbonyl group of each furoate appeared near 1750 and 1730 cm−1 in the IR spectrum. On the other hand, the furoic acids with 5-aryl substituents afforded 5-arylpentanoate or 5-arylpent-3-enoate as main products. These esters would be produced as a result of reductive cleavage at C5 of 5-aryl-2,5-dihydrofuroates formed as intermediates.
  • Kazuhiko Sakamoto, Michinori Oki
    1975 Volume 48 Issue 2 Pages 497-504
    Published: 1975
    Released: March 27, 2006
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    A series of diazadioxo[n]paracyclophane derivatives with two alkoxy groups at the benzene ring were prepared. The conformation of amide groups in these compounds were studied by infrared, PMR, and 13C NMR spectra to draw a conclusion that both amide groups are s-trans. Thus the infrared absorptions at 3430 and 3405 cm−1 are attributed to N–H···π interacting and N–H···O bonded trans forms, respectively. NCH2 protons, which are separated by 5 bonds from the asymmetric center, as well as benzylic protons, were found to be non-equivalent when the rotation of the aromatic ring was slow. PMR spectra of the compounds studied at various temperatures indicate that introducing alkoxy groups in place of methyls at the benzene ring increases the barrier to rotation of the aromatic ring to a great extent.
  • Tsuneo Sowa, Kozo Tsunoda
    1975 Volume 48 Issue 2 Pages 505-507
    Published: 1975
    Released: March 27, 2006
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    The synthesis of 2,2′-O-anhydro(1-β-D-arabinofuranosyl) cytosine (3a) and 2,2′-O-anhydro(1-β-D-arabinofuranosyl) uracil (3b) is described. The active intermediates, 2′,3′-O-sulfinyl cytidine (2a) and 2′,3′-O-sulfinyl uridine (2b), were prepared from the corresponding nucleosides (1a or 1b) by successive treatment with thionyl chloride in acetonitrile and with water. The 2,2′-O-anhydropyrimidine nucleosides were formed quantitatively by heating the intermediates in an acidic aqueous solution or in N,N-dimethylformamide in the presence of sodium acetate. The treatment of the anhydronucleosides with alkali gave the corresponding arabinonucleosides.
  • Makoto Yamamoto, Noboru Sugiyama
    1975 Volume 48 Issue 2 Pages 508-511
    Published: 1975
    Released: March 27, 2006
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    2-Methyl-4H-pyran-4-ones formed metalated products in the presence of sodium amide in liquid ammonia, and the metalated product reacted with alkyl and aralkyl halides or carbonyl compounds to give alkylated or condensed products. Self condensation reactions of 2-methyl-4H-pyran-4-ones also occurred in liquid ammonia to give flavone and the γ-pyrone dimer.
  • Hiizu Iwamura, Hiroshi Kihara
    1975 Volume 48 Issue 2 Pages 512-516
    Published: 1975
    Released: March 27, 2006
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    Tetracyclo[4.2.0.02,805,7]oct-3-ene (1) is estimated by a MINDO MO calculation to be moderately strained. Interaction between the ethylenic π orbital and the Walsh orbitals of the two cyclopropane rings is extensive in the ground state structure of 1. The third highest occupied MO is an out-of-phase combination of the ethylenic 2pπ AO’s on C3 and C4, while the corresponding in-phase combination appears in the lower unoccupied MO’s. The interconversion between 1 and bicyclo[4.2.0]octa-2,4,7-triene (2) is a typical symmetryallowed reaction as revealed by a smooth change in bond indices along the reaction coordinates. The isomerization of substituted cyclooctatetraenes via 1 and 2 (Eq. (2)) is predicted to be possible at elevated temperatures. The symmetry-allowed degenerate valence isomerization of 1 (Eq. (3)) is energetically less favorable due to skeletal constraint.
  • Jun-ichi Aihara
    1975 Volume 48 Issue 2 Pages 517-520
    Published: 1975
    Released: March 27, 2006
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    Resonance energies of annulenes and radialenes were estimated on the basis of the π-bond energies of infinitely large annulene and radialene, respectively. The widely accepted Hückel’s (4n+2)π rule was verified for annulenes, whereas radialenes were substantially nonaromatic regardless of the number of π-electrons.
  • Nobuo Adachi, Kiyoshi Kikukawa, Makoto Takagi, Tsutomu Matsuda
    1975 Volume 48 Issue 2 Pages 521-525
    Published: 1975
    Released: March 27, 2006
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    The reaction of open-chain unconjugated dienes with palladium acetate in acetic acid was investigated with particular reference to the behavior of the two double bonds in the course of the acetoxylation. 1,5-Hexadiene produced 3-acetoxymethylenecyclopentane (64%), but 2,6-octadiene bearing two terminal methyl groups gave open-chain acetoxylated products: 3-acetoxy-1,6-octadiene (46%) and 7-acetoxy-2,5-octadiene (47%). The reactions of 1,6-heptadiene and diallyl ether are found to proceed via abnormal anti-Markovnikov addition to afford cis and trans 1-acetoxy-1,6-heptadienes (63%) and γ-acetoxyallyl allyl ethers (84%), respectively. No participation of the second double bond has been observed in the reaction of 1,7-octadiene. The behaviors of these dienes to palladium acetate can be reasonably explained by assuming the formation of π,σ-palladium species possessing a stable pseudo-six membered ring.
  • Shingo Miyajima, Osamu Simamura
    1975 Volume 48 Issue 2 Pages 526-530
    Published: 1975
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    Autoxidation of 1, c-3, c-5- or 1, c-3, t-5-trimethylcyclohexane with oxygen in the presence of azobisisobutyronitrile at 60°C and subsequent reduction with lithium aluminium hydride gave 1, t-3, t-5- and 1, c-3, c-5-trimethyl-r-1-cyclohexanol in the same ratio of 1/0.85. Such an almost random attack of oxygen on both sides of intermediate methylcyclohexyl radicals was also observed in autoxidation of 1,2-dimethyl-, 1,4-dimethyl-, and 1,1,3,5-tetramethylcyclohexanes. Approximate relative reactivities of tertiary hydrogens in various steric environments in methylcyclohexanes towards abstraction were determined. Steric effects on the attack of oxygen and the abstraction of hydrogen are discussed.
  • Shingo Miyajima, Sadao Ichihara, Osamu Simamura
    1975 Volume 48 Issue 2 Pages 531-532
    Published: 1975
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    The reaction of hydrogen bromide with cyclohexene or 1-methylcyclohexene in the presence of oxygen, followed by reduction with lithium aluminium hydride afforded trans-2-bromocyclohexanol or t-2-bromo-1-methyl-r-1-cyclohexanol. These findings show that oxygen attacks intermediate bromocyclohexyl radicals formed by addition of a bromine atom to a double bond exclusively on the side opposite to the bromine substituent. Mechanistic implications are discussed.
  • Shingo Miyajima, Osamu Simamura
    1975 Volume 48 Issue 2 Pages 533-535
    Published: 1975
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    Autoxidation of cis-2-bromo-1-methylcyclohexane and subsequent reduction of the resulting hydroperoxide with lithium aluminium hydride gave only t-2-bromo-1-methyl-r-1-cyclohexanol to the exclusion of the c-2-bromoisomer. The reactivity ratio of the C–1 hydrogen in cis-2-bromo-1-methylcyclohexane to that in 1, c-3, c-5-trimethylcyclohexane towards abstraction was estimated to be about 4 by competitive oxidation experiments. An explanation for the acceleration of hydrogen abstraction and the stereospecific oxygen attack on the intermediate radical is given in terms of a bromine bridged radical. Autoxidation of a sample of 2-bromo-1-methylcyclohexane, containing about 90% of the trans isomer, took place very slowly as compared with the cis isomer.
  • Toshimasa Sakaki, Akio Wakahara, Takaji Fujiwara, Ken-ichi Tomita
    1975 Volume 48 Issue 2 Pages 536-540
    Published: 1975
    Released: March 27, 2006
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    The crystal structure of 5-methoxyindole-3-acetic acid (5-MIAA) has been solved by application of the direct method with symbolic addition procedure. 5-MIAA, colorless transparent prism, is monoclinic, space group C2/c, with lattice parameters: a=34.461(9) Å, b=6.150(5) Å, c=9.480(5) Å, β=96.14(2)°, Z=8. The molecules are hydrogen-bonded into dimers related by the center of symmetry, which are held together in an infinite double-layered sheet structure perpendicular to the a-axis with N–H···O hydrogen bond between indole nitrogen and carboxyl oxygen atoms. The methyl groups of adjacent molecules contact to each other by van der Waals forces. The conformation of the side-chain is quite distinguishable from that of indole-3-acetic acid. The dihedral angle between carboxyl and indole planes is 59.5° in this molecule, whereas that is 90.0° in indole-3-acetic acid, and the carboxyl group sticks out to be perpendicular to the indole plane.
  • Yukito Murakami, Hiroki Kondo
    1975 Volume 48 Issue 2 Pages 541-545
    Published: 1975
    Released: March 27, 2006
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    The effects of metal ions and detergents on the pyridoxal-catalyzed α,β-elimination reaction of S-phenylcysteine have been investigated in 0.01 M borate buffer at 50 °C (the copper ion catalysis at 40 °C in the presence of CTAB micelles). Both copper(II) and nickel(II) ions markedly accelerated the elimination reaction of S-phenylcysteine. Since the catalytic efficiency of nickel(II) seems to be obtained due to the poor coordination ability of the leaving group in the present reaction, the previous working hypothesis which was provided for the elucidation of catalytic roles of metal ions in the α,β-elimination of O-phosphothreonine has now been approved. Among cationic, anionic, and non-ionic detergents employed in this work as apoenzyme models, only CTAB of cationic nature showed a considerable rate acceleration even in the absence of metal ions. The micellar binding constant was evaluated from the saturation-type correlation between reaction rate and CTAB concentration. The surfactant micelles demonstrated some enzyme-like features of catalysis in the pyridoxal-promoted α,β-elimination reaction, where the reaction is controlled by the entropy term. The CTAB catalysis was greatly inhibited by organic and inorganic anions due to the electrostatic nature of the micellar surface. The catalytic mechanisms for the micellar reactions and their significance as an enzyme model system are discussed.
  • Shigenobu Nakayama, Masaaki Yoshifuji, Renji Okazaki, Naoki Inamoto
    1975 Volume 48 Issue 2 Pages 546-548
    Published: 1975
    Released: March 27, 2006
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    Phenylphosphonic and phenylphosphonothioic dichlorides were dechlorinated with magnesium to generate phenylphosphinylidene and phenylphosphinothioylidene, respectively, in the presence of several 1,3-dienes. Reactions of phenylphosphinothioylidene with 2,3-dimethylbutadiene and 1,3-cyclohexadiene gave Diels-Alder type reaction products, that is, 3,6-dihydro-1,2-thiaphosphorin derivatives (5 and 6) and 6-phenyl-5,6-thiaphosphabicyclo[2.2.2]oct-2-ene 6-sulfide (14), respectively. Reaction of 2,3-diphenylbutadiene with phenylphosphinothioylidene afforded 1,2,4,5-tetraphenyl-1,2,3,6-tetrahydro-1,2-diphosphorin 1,2-disulfide (10), whereas that with phenylphosphinylidene gave 1,3,4-triphenyl-3-phospholene 1-oxide (12). The differences of these reactions have been discussed.
  • Masahiro Tada, Yoshihiko Moriyama, Yoshiaki Tanahashi, Takeyoshi Takah ...
    1975 Volume 48 Issue 2 Pages 549-552
    Published: 1975
    Released: March 27, 2006
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    4,6-Dimethylcoumarin (3) was converted to an enantiomer (1b) of farfugin A, via a levorotatory carboxylic acid (5b). This led to the absolute configuration (1a) for farfugin A.
  • Hisao Nishihara, Koji Nishihara, Tamio Uefuji, Naokazu Sakota
    1975 Volume 48 Issue 2 Pages 553-555
    Published: 1975
    Released: March 27, 2006
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    NMR and CD studies were carried out for acetyl-L-proline, isovaleroyl-L-proline, isobutyroyl-L-proline, pivaloyl-L-proline and benzoyl-L-proline. It was found that N-acetyl-L-proline has two rotational isomers about the amide bond, S-trans and S-cis conformers even at room temperature, and that the population of the former is greater than that of the latter except for pivaloyl-L-proline, which consists only of the S-trans conformer. The two isomeric N-acyl-L-prolines showed different CD peaks of opposite sign associated with the n→π* transition of the amide group.
  • Sumio Umezawa, Hiroshi Sano, Tsutomu Tsughiya
    1975 Volume 48 Issue 2 Pages 556-559
    Published: 1975
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    The isopropylidene derivative (4) of benzyl dihydrostreptoside and 3,4,6-tri-O-acetyl-2-amino-N-anisylidene-2-deoxy-α-L-glucopyranosyl bromide (7) were prepared, and they were coupled by a modified Koenigs-Knorr condensation. After hydrolysis of the N-ankylidene group of the product, N-methoxycarbonylation followed by N-methylation was accomplished to afford the fully protected derivative (9) of dihydrostreptobiosamine, which was, after deblocking, led to benzyl dihydrostreptobiosaminide and dihydrostreptobiosamine.
  • Sumio Umezawa, Yoshikazu Takahashi, Tsutomu Tsuchiya
    1975 Volume 48 Issue 2 Pages 560-562
    Published: 1975
    Released: March 27, 2006
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    Reaction of streptidine with excess benzyloxycarbonyl chloride, followed by partial alkaline hydrolysis, gave di-N-benzyloxycarbonylstreptidine (1), which, by treatment with 3,4-dihydro-2H-pyran, gave a tetra-O-tetra-hydropyranyl derivative (3). Acetylation of 3 then gave a di-N-acetyl derivative (4), which was, after removal of the tetrahydropyranyl groups, allowed to react with 1,1-dimethoxycyclohexane to furnish di-N-acetyl-di-N-benzyloxycarbonyl-O-cyclohexylidenestreptidine (6). This is the first preparation of a useful intermediate for the synthesis of streptidine glycosides.
  • Sumio Umezawa, Tetsuro Yamasaki, Yutaka Kubota, Tsutomu Tsuchiya
    1975 Volume 48 Issue 2 Pages 563-569
    Published: 1975
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    Dihydrostreptomycin has been synthesized from dihydrostreptobiosamine and streptidine. A glycosyl chloride derivative (10) of the former was coupled with a protected derivative (26) of the latter to give a mixture of four isomeric glycosides, which were separated by chromatography. Deblocking of the desired glycoside led to dihydrostreptomycin. Several other protected derivatives of dihydrostreptobiosamine have also been described.
  • Mitsuhiro Kinoshita, Akito Hagiwara, Shinpei Aburaki
    1975 Volume 48 Issue 2 Pages 570-575
    Published: 1975
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    Natural (−)(3S,4S)-4-amino-3-hydroxy-6-inethylheptanoic acid (10a) present in pepstatins, specific inhibitors of acid proteases, and its (+) (3S,4R) diastereomer (10b) were synthesized starting from 3-deoxy-1,2-O-isopropylidene-α-D-erythro-pentodialdo-1,4-furanose (1) through highly stereoselective and stereospecific routes. The partial pep tide of pepstatin Ac, N-(acetyl-L-valyl-L-valyl)-(3S,4S)-4-amino-3-hydroxy-6-methylheptanoic acid (15a) and its (3S,4R) diastereomer (15b) were synthesized via azide-coupling of the t-butyl esters of 10a and 10b with acetyl-L-valyl-L-valine azide, respectively. Compound 15a inhibited proteolysis by pepsin, however, the diastereomer 15b showed no inhibition against pepsin.
  • Hiroshi Suginome, Hajime Takahashi
    1975 Volume 48 Issue 2 Pages 576-582
    Published: 1975
    Released: March 27, 2006
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    The Beckmann rearrangement of either syn-5β-cholestan-6-one oxime or anti-5β-cholestan-6-one oxime with polyphosphoric acid at 90° takes place prior to the syn-anti equilibration of these isomers. In the photo-Beckmann rearrangement a pair of lactams, in both of which the original configurations of Cα with respect to the oximino-group of the starting oximes were retained, was produced irrespective of the configuration of the oximino-group of the starting oxime. The difference of the amounts between two isomeric lactams formed in each photolysis is small but the lactams due to the migration of the more substituted carbon are produced always in a slightly larger amount than those due to the migration of the less substituted carbon. Oxygen does not affect the formation of lactams. All these results indicate a concerted reorganization of an excited singlet oxaziridine intermediate, hydrogen-bonded with protic solvent molecule (s), into the corresponding lactams. During these studies, the photochemical epimerization of 5β-steroid-6-one into the 5α-isomer by α-cleavage-recombination sequence was observed.
  • Fumio Toda, Eishiro Todo
    1975 Volume 48 Issue 2 Pages 583-585
    Published: 1975
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    The photolysis of 3,4-bis(hydroxydiphenylmethyl)cyclobut-3-ene-1,2-dione (1) in benzene afforded 4,4,8,8-tetraphenyl-3,7-dioxabicyclo[3.3.0]octane-2,6-dione (3) in an 80% yield. The photolysis of 1 in MeOH afforded 4,4,8,8-tetraphenyl-3,7-dioxabicyclo[3.3.0]oct-1(5)-ene-2,6-dione (4), 4-methoxycarbonyl-3,3-diphenyl-5-diphenylmethylene-2-oxacyclopentan-1-one (5), and 4-carboxy-3,3-diphenyl-5-diphenylmethyl-2-oxacyclopent-4-en-1-one (6), in 3, 8, and 22% yields respectively. The mechanisms of the formation of the 5 and 6 are discussed. The photolysis of 3-hydroxydiphenylmethyl-4-diphenylmethoxymethylcyclobut-3-ene-1,2-dione (14) and 3,4-bis(diphenylmethyl)cyclobut-3-ene-1,2-dione (18) was also investigated.
  • Masahiro Minabe, Kazuo Suzuki
    1975 Volume 48 Issue 2 Pages 586-590
    Published: 1975
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    The Michael reactions of 2-chloro- and 2,7-dichloro-9,9′-bifluorenylidenes with fluorenes were investigated. Structures of these products were confirmed by syntheses through the well-established reactions of 9-lithiofluorenes and 9-bromo-9,9′-bifluorenyls. The formation of some abnormal compounds is explained by intermediary formation of 2,7-dichloro-9,9′-bifluorenylidene from the reaction of 9,9′-bifluorenylidene with 2,7-dichlorofluorene as with the bromo-derivatives. The corresponding fluoro- and iodo-series gave predominantly normal addition products. These differences are explained in terms of the inductive and steric effects of the halogen substituents.
  • Yasukazu Yokoyama, Katsuya Shibata, Osamu Fujii, Eiji Iwamoto
    1975 Volume 48 Issue 2 Pages 591-595
    Published: 1975
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    The reaction of 1,4-bis(ethoxycarbonyl)-2,5-diamino-1,4-cyclohexadiene(Ia) with aniline in aprotic solvents gave N,N′-diphenylurea, whereas in the presence of a proton acid this reaction gave an amine-exchanged product,14-bis(ethoxycarbonyl)-2,5-dianilino-1,4-cyclohexadiene(Ib). However, when 2-aminopyridine was used in place of aniline for this reaction, 1,4-bis(ethoxycarbonyl)-2,5-bis(2-pyridylamino)-1,4-cyclohexadiene(Ic) was not isolated but its cyclyzed analogue, 6,7,14,15-tetrahydropyrido[2,1-b]pyrido[1′,2′:1,2]pyrimido[4,5-g]quinazoline-7,15-dione(IIa), was obtained. The reaction of 2-amino-6-methylpyridine with la also gave a quinazoline derivative without producing a 1,8-naphthyridine derivative. Since this reaction took place easily in a weak acid, AcOH, this cyclization could proceed by an intramolecular proton-transfer mechanism.
  • Fumio Suzuki, Michinori Oki
    1975 Volume 48 Issue 2 Pages 596-604
    Published: 1975
    Released: March 27, 2006
    JOURNALS FREE ACCESS
    Several 9-benzyltriptycene derivatives were prepared by addition of benzynes to 9-benzylanthracenes. Rotation about the C9–Cbenzyl bond of compounds with a substituent at a peri-position to the benzyl group was found to be frozen at low temperatures on the NMR time scale but not at room temperature. In contrast, compounds with two substituents at two peri-positions to the benzyl group showed a frozen rotation about the C9–Cbenzyl bond at room temperature. Distribution of the conformers, as judged from the PMR intensities, showed preference to the dl-isomers in spite of the fact that they are the ones which are highly disfavored by steric effects. Interpretation of the phenomenon was based on the fact that attractive interactions, mainly charge-transfer type, exist between the substituted benzo group in the triptycene skeleton and the benzene ring in the benzyl group.
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