-
Yasutake Teraoka, Hisashi Fukuda, Shuichi Kagawa
1990 Volume 19 Issue 1 Pages
1-4
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Perovskite-type oxides showed the catalytic activity for NO decomposition above 773 K, which depended largely on constituent metal cations and their composition. Results obtained indicate that perovskite-type oxides such as La
0.8Sr
0.2CoO
3 are a promising NO decomposition catalyst having high activity and thermal stability at elevated temperatures.
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Kenji Takehara, Yasuhiko Oozono, Shigeru Oda, Kazuaki Isomura, Hiroshi ...
1990 Volume 19 Issue 1 Pages
5-8
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Surface pressure-area (π-A) isotherms of monolayers of amphiphilic compounds, in which one phenyl ring of 4′-dodecyloxybiphenyl-4-carboxylic acid was replaced by a pyrazine, pyridine, or pyrimidine nucleus, were measured. The difference of π-A isotherms depending on the structure of heterocycles can be understood in terms of interaction between chromophores.
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Tsugio Kitamura, Ichizo Nakamura, Takashi Kabashima, Shinjiro Kobayash ...
1990 Volume 19 Issue 1 Pages
9-12
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Photolysis of 1-bromo-2, 2-bis(
p-alkoxyphenyl)-1-phenylethenes in the presence of sodium ethoxide in ethanol gave ipso adducts bearing 1,2-aryl rearranged structure, indicating that ipso substitution proceeds via vinyl cations.
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Kazumasa Honda, Midori Goto, Masayasu Kurahashi
1990 Volume 19 Issue 1 Pages
13-16
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Crystal structure of 5-aminovaleric acid has been determined by synchrotron X-ray powder diffraction. Diffraction data of high angle-resolution and of accurate intensity were collected by a large-radius (28.65 cm) Weissenberg camera using monochromatic X-rays. The structure was successfully solved from these data by combination of Patterson synthesis and trial and error method, followed by Rietveld refinement.
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Zhong-Fan Liu, Boon H. Loo, Ryo Baba, Akira Fujishima
1990 Volume 19 Issue 1 Pages
17-20
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Ordered molecular structure has been observed by scanning tunneling microscopy (STM) in the disordered films of an azobenzene derivative on highly oriented pyrolytic graphite (HOPG) surfaces. The disordered films were formed by a direct deposition method. The present result gives the first report on the observation of tip-induced ordered molecular structure from disordered films by STM, and it demonstrates the possibility of orderly arranging molecules on surfaces through the action of an STM tip.
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Koji Kano, Kazuhiro Yoshiyasu, Shizunobu Hashimoto
1990 Volume 19 Issue 1 Pages
21-24
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Asymmetric complexation between bilirubin (BR) and nucleosides has been studied in water (pH 10.8) by UV-vis absorption and circular dichroism (CD) spectroscopy. The complexes of BR with ribo- and deoxyribonucleosides show the plus to minus bisignated CD signals, which indicate that BR in these complexes selectively takes the (R)-helix conformation. Thymine and uracil arabinosides exhibit the oppositely signed CD spectra. A multi-point attachment model may explain the asymmetric complexation.
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Yuichi Ishikawa, Taisei Nishimi, Toyoki Kunitake
1990 Volume 19 Issue 1 Pages
25-28
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The steric structures of helices and vesicles formed from bilayer membranes of ammonium amphiphiles were observed without metal coating by high-resolution scanning electron microscopy. These observations agreed with those made by transmission electron microscopy.
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Nobuo Kimizuka, Hiroyuki Ohira, Miho Tanaka, Toyoki Kunitake
1990 Volume 19 Issue 1 Pages
29-32
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Novel amphiphiles in which four long alkyl chains are connected to the single trimethylammonium head group via amino acid residues gave clear dispersions upon sonication. Formation of bilayer membranes was confirmed by electron microscopy, differential scanning calorimetry, and fluorescence depolarization.
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Robert Chênevert, Michel Desjardins, René Gagnon
1990 Volume 19 Issue 1 Pages
33-34
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Hydrolysis of racemic chloral acetyl methyl acetal using lipase from Candida cylindraceae, porcine pancreatic lipase or cholesterol esterase gives the optically pure (−)-enantiomer whereas hydrolysis using subtilisin gives the pure (+)-enantiomer.
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Yasuyuki Aratono, Chiaki Sagawa, Mikio Nakashima, Masakatsu Saeki, Tak ...
1990 Volume 19 Issue 1 Pages
35-38
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Chemical effects caused by the
6Li(n,α)
3H nuclear reaction in α-LiFeO
2 were studied with Mössbauer spectroscopy. Magnetite was observed on the irradiation. The amount of magnetite increased with irradiation fluence until about 10
22 m
−2 was reached. It then became a constant value of about 50% of the α-LiFeO
2 in the iron atom ratio. The G value for the formation of magnetite was initially 10
−2 and decreased to about 10
−3 at a fluence of 3 × 10
22 m
−2.
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Koji Chiba, Hideyuki Tagaya, Masa Karasu, Tsuyoyuki Ono, Masashi Kugiy ...
1990 Volume 19 Issue 1 Pages
39-42
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Active methylene compounds were carboxylated by employing the reagent system, diphenylcarbodiimide and potassium carbonate, in dimethyl sulfoxide at room temperature and atmospheric pressure. The reaction proceeded even in the absence of carbon dioxide, but the carboxylation easily proceeded in carbon dioxide atmosphere.
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Kazuhisa Hiratani, Masayo Nomoto, Hideki Sugihara, Tatsuhiro Okada
1990 Volume 19 Issue 1 Pages
43-46
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The fluorescence intensity of 2,9-di-
n-butyl-1,10-phenanthroline was drastically enhanced in the presence of lithium ion, but not sodium, potassium, and beryllium ions.
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Eiichi Suzuki, Yoshio Ono
1990 Volume 19 Issue 1 Pages
47-50
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Trimethoxysilane was obtained with a 98% selectivity and at an 82% silicon conversion in 5 h of reaction time, when methanol (99 kPa) was fed at 543 K into a fixed-bed reactor containing silicon powder preheated with copper(I) chloride at 623 K for 3 h.
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Hisanobu Ogoshi, Hitoshi Hatakeyama, Kazuo Yamamura, Yasuhisa Kuroda
1990 Volume 19 Issue 1 Pages
51-54
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Axial ligation behaviors of nucleobases to Rh(III)porphyrins were investigated. Except the case of TPP·Rh(III)-1-methylthymine system, tight 1:1 complexations were observed between Rh(III)porphyrins and nucleobases and their binding constants were determined by spectroscopic titration.
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Tsutomu Inoue, Seiichi Inoue, Kikumasa Sato
1990 Volume 19 Issue 1 Pages
55-58
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The treatment of
o-(1-(alkylthio)alkyl)phenols with Lewis acid resulted in the formation of
o-quinone methides by the novel 1,4-dethiolation process, which, being activated with Lewis acid, reacted
in situ with various dienophiles in the manner of Diels–Alder reaction in high efficiency.
o-Quinone allide, provided from
o-(1-(alkylthio)allyl)phenol, also behaved as heterodienes.
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Shuichi Ôi, Masayuki Shijo, Sotaro Miyano
1990 Volume 19 Issue 1 Pages
59-62
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A chiral stationaly phase (CSP) comprised of axially chiral 1,1′-bianthracene-2,2′-dicarboxylic acid chemically bonded to aminopropylsilanized silica gel was prepared for HPLC separation of enantiomers. This phase showed far better discrimination for a wide range of aromatic and aliphatic alcohols and diols as 3,5-dinitrophenylcarbamates than that which was prepared from 1,1′-binaphthalene-2,2′-dicarboxylic acid.
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Kanichiro Takamizawa, Yoshiko Urabe
1990 Volume 19 Issue 1 Pages
63-66
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Micro DSC measurement of solution-crystallized heptacosane was confirmed to be reliable down to a sample weight of 0.01 mg order. However, a close contact between the sample of such a slight amount and the sample pan resulted in a decrease in the transition enthalpy. This effect was interpreted from an entropic standpoint.
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Satoshi Inoki, Teruaki Mukaiyama
1990 Volume 19 Issue 1 Pages
67-70
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In the presence of a catalytic amount of bis(1-morpholinocarbamoyl-4,4-dimethyl-1,3-pentanedionato)cobalt(II), various 5-hydroxy-1-alkenes are converted to the corresponding 2-hydroxymethyltetrahydrofurans in good yields with extremely high trans selectivities by the oxidative cyclization with molecular oxygen. The yields of cyclization products are improved by addition of hydroperoxide.
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Makoto Ogawa, Tokuhiko Handa, Kazuyuki Kuroda, Chuzo Kato
1990 Volume 19 Issue 1 Pages
71-74
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Organoammonium-montmorillonites were formed from dehydrated sodium montmorillonite and organoammonium halides by solid-solid reactions. The formation depended on the sizes and counter anions of the ammonium ions used. The behavior was different from that observed in a conventional solution method.
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Tetsuo Osa, Yoshitomo Kashiwagi, Kenji Mukai, Akio Ohsawa, James M. Bo ...
1990 Volume 19 Issue 1 Pages
75-78
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The graphite felt electrode, coated with ca. 3 wt% polyacrylic acid, was modified by successive reactions with hexamethylenediamine (for cross-linking), 4-amino-2,2,6,6-tetramethylpiperydinyl-1-oxyl(4-amino-TEMPO) and diazomethane (for methylation). Properties of the electrode, were compared with a non-crosslinked and non-methylated one, a crosslinked and a non-methylated one, and a crosslinked and incompletely methylated one; the present electrode was stable and oxidized nerol to neral selectively with turnover number > 1560.
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Yong Hae Kim, Sang Chul Lim, Hyoung Rae Kim, Dae Chul Yoon
1990 Volume 19 Issue 1 Pages
79-82
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Various unsymmetrical and symmetrical diakyl sulfoxides or alkyl aryl sulfoxides reacted with
N,
N′-dichloro-
p-toluenesulfonamide to yield the corresponding α-chlorosulfoxide in excellent yields under mild and neutral conditions in high regioselectivity of monochlorination at α-position of sulfoxides.
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Masato Koreeda, Irene A. George
1990 Volume 19 Issue 1 Pages
83-86
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The synthesis of (22
R)-22-hydroxycholesterol, featuring formation of three contiguous chiral centers (C-17, 20, and 22) in a single step by the use of a 6-endo α-silyl radical-mediated cyclization is presented. Additionally, an interesting protiodesilylation used to activate a cyclic siloxane towards C–Si bond oxidation, and a modified, bulky aryl thionocaronate reagent for regioselective diol-monodeoxygenation are described.
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Zhuang Jin Zhong, Naohide Matsumoto, Hisashi Okawa, Sigeo Kida
1990 Volume 19 Issue 1 Pages
87-90
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Two types of hetero–metal assemblies {NBu
4CuCr(ox)
3]}
x (
1) and {[{Cu(bpy)}
2Cr(ox)
3]NO
3}
x (
2)(NBu
4 = tetrabutylammonium ion, ox = oxalate ion, bpy = 2,2′-bipyridine, x = infinite number) have been synthesized and their cryomagnetic properties (4.2–300 K) have been examined. The compound
1 has an oxalate-bridged three-dimensional lattice and show a ferromagnet-like property (Curie point 7 K): the moment (per CrCu) increases from 4.37 μ
B at 300 K to 14.80 μ
B at 9 K and diverges below 9 K. The compound
2 also shows a ferromagnetic interaction and its moment (per CrCu
2) increases from 4.82 μ
B at 300 K to 8.78 μ
B at 5 K.
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Tomoo Nakazawa, Mariko Ishihara, Masakazu Yamaguchi, Yoshikazu Sugihar ...
1990 Volume 19 Issue 1 Pages
91-92
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3-Substituted 8
H-3-azaheptalen-8-ones were synthsized in good yields by photoirradiation of corresponding 7-substituted 7-azanorbornadienes fused with tropone in ethanol with a 450-W Hg lamp through pyrex filter.
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Masao Ohashi, Koji Uyeoka, Shoji Yamanaka, Makoto Hattori
1990 Volume 19 Issue 1 Pages
93-96
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Tetrahydrofuran (THF) is co-intercalated with lithium in β-ZrNCl. Two highly crystalline co-intercalation phases were obtained as single phases by the reaction of the chemically transported β-ZrNCl and lithium-naphthalene in THF. The molecular arrangements in the interlayer spaces were estimated on the basis of the one-dimensional electron-density distribution maps.
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Kiyotaka Furusawa, Katsuhiko Ueno, Tatsuo Katsura
1990 Volume 19 Issue 1 Pages
97-100
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The reaction of ribonucleosides with di-
t-butylsilyl diester such as dinitrate, diperchlorate and ditriflate in DMF gave selectively 3′,5′-
O-(di-
t-butylsilanediyl)ribonucleosides in high yield. The conformation analysis by
1H NMR spectroscopy and X-ray crystallography showed that the product has a restricted conformation analogous to that observable in 3′,5′-cyclic nucleotides.
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Takeshi Yamamura, Hiroaki Kurihara, Nobuhumi Nakamura, Reiko Kuroda, K ...
1990 Volume 19 Issue 1 Pages
101-104
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Crystalline (Ph
3MeP)
2[Ni(edt)
2] was isolated and studied by X-ray analysis and X-ray absorption (EXAFS/XANES) methods, which revealed a square planar {NiS
−4} geometry for the chromophore. The results were discussed in terms of the nickel site of hydrogenases.
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Shuji Kanemasa, Osamu Uchida, Eiji Wada, Hidetoshi Yamamoto
1990 Volume 19 Issue 1 Pages
105-108
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Cycloadditions of the
N-titanated azomethine ylides, derived from
t-butyl (benzylideneamino)acetate, with α,β-unsaturated esters afford three different types of cycloadducts, depending upon the structure of dipolarophiles and the reaction temperature. In the reactions at room temperature, exo cycloadducts are exclusively produced, while either endo cycloadducts or regioisomeric ones are obtained in the reactions at a low temperature.
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Seiichi Takano, Minoru Moriya, Yoshiharu Iwabuchi, Kunio Ogasawara
1990 Volume 19 Issue 1 Pages
109-112
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A chiral route to both enantiomers of esermethol, the key synthetic precursor of physostigmine, has been established starting from (
S)-
O-benzylglycidol via separation of the diastereomeric intermediates. (−)-Physostigmine obtainable from the (−)-enantiomer has been first transformed into (−)-norphysostigmine, the only unsynthesized member of the alkaloid group ever determined.
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Masaru Hojo, Ryoichi Masuda, Etsuji Okada
1990 Volume 19 Issue 1 Pages
113-114
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(
E,
E)-4-Trifluoroacetyl-1,3-butadienyl sulfides are prepared from 2,4-diethoxy-6-trifluoromethyl-3,4-dihydro-2
H-pyran with thiols in the presence of acid catalysts.
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Teiichiro Ogawa, Toshifumi Yoshidome, Hirofumi Kawazumi
1990 Volume 19 Issue 1 Pages
115-118
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The electron energy-loss spectrum of methanol was measured at incident electron energies from 100 to threshold +2 eV. There were several intense bands assignable to the Rydberg transitions. Three singlet-triplet transitions were observed at 5.7–7.0, 7.3–7.6 and 8.8–9.5 eV at low incident electron energies.
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Masahiro Hiramoto, Yasuhisa Kishigami, Masaaki Yokoyama
1990 Volume 19 Issue 1 Pages
119-122
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Doping effect on an organic solar cell composed of two-layer thin pigment films of metal-free phthalocyanine (H
2Pc) and perylene tetracarboxylic derivative (Me-PTC) was investigated. When H
2 or NH
3 was doped to the Me-PTC film during vacuum deposition, the photocurrent density drastically increased and the power conversion efficiency of the cell reached about 1% even under 75 mW cm
−2 white light.
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Etsuo Hasegawa, Masaki Fukuzumi, Hiroyuki Nishide, Eishun Tsuchida
1990 Volume 19 Issue 1 Pages
123-126
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A new tetraphenylporphinatoiron(II) having only one amphiphilic chain with a phosphoserine group as a hydrophilic end group was synthesized. The complex with 1-dodecyl-2-methylimidazole embedded in phospholipid bilayer formed an oxygen adduct and the oxygen-binding rate constant was much smaller than that of the heme having four amphiphilic chains.
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Tatsuo Fujinami, Hitoshi Ishikawa, Hiromitsu Takaoka, Shin-ichi Fukuza ...
1990 Volume 19 Issue 1 Pages
127-128
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Anionic conductivity of poly(vinyl chloride)-tetrabutylammonium iodide composite film has been remarkably increased by the addition of organotin compounds. At a high content of tributyltin iodide, the conductivity has been enhanced up to the order of 10
−4 S/cm at 25 °C.
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Teruaki Mukaiyama, Shu Kobayashi, Hiromi Uchiro, Isamu Shiina
1990 Volume 19 Issue 1 Pages
129-132
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Highly enantioselective aldol reaction of silyl enol ethers with aldehydes is performed by the use of a catalytic amount of chiral diamine coordinated tin(II) triflate according to a slow addition procedure.
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Hisatoshi Nishimura, Hirotaka Nagao, F. Scott Howell, Masao Mukaida, H ...
1990 Volume 19 Issue 1 Pages
133-136
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Nitro–Nitrito isomerization occurs reversibly when a formal oxidation state of the central metal atom is changed; a nitro complex of Ru(II) gives a nitrito complex of Ru(IV), which is capable of being returned to the original complex by a moderate reduction.
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Tadao Kondo, Kaori Oki, Kumi Yoshida, Toshio Goto
1990 Volume 19 Issue 1 Pages
137-138
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Structure of violdelphin was determined. It is a delphinidin derivative containing two molecules of p-hydroxybenzoic acid.
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Ryu Sato, Shin-ichi Satoh, Minoru Saito
1990 Volume 19 Issue 1 Pages
139-142
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Many olefins trapped active sulfur species generated from 5
H-benzo[
f]-1,2,3,4-tetrathiepin (BTTP) or 6
H-benzo[
g]-1,2,3,4,5-pentathiocin (BPTC) in DMSO to give [2+3], [4+2], or [6+3] cycloadducts.
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Hiroki Hotta, Takatsugu Suzuki, Sotaro Miyano
1990 Volume 19 Issue 1 Pages
143-144
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Grignard reagents formed from 1-bromonaphthalenes smoothly displaced the 1-methoxyl group of 1-methoxy-2-naphthoic esters to provide a facile route to 1,1′-binaphthyl-2-carboxylic acids in excellent yields; the reaction of (
S)-1-phenylethyl esters caused asymmetric induction in the joining of the two naphthalene rings in up to 51% optical yield.
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Tatsuo Higa, Junichi Tanaka, Toshikatsu Kohagura, Tomoshige Wauke
1990 Volume 19 Issue 1 Pages
145-148
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Four new polyacetylenes have been isolated from three species of hermatypic corals,
Montipora sp,
M. mollis, and
Pectinia lactuca. These compounds, representing the first such metabolites of coelenterates, exhibited ichthyotoxicity and inhibited the growth of some bacteria and fungi.
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Masaki Ue, Yutaka Ohnishi, Kazuya Kobiro, Kiyomi Kakiuchi, Yoshito Tob ...
1990 Volume 19 Issue 1 Pages
149-150
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A total synthesis of (±)-3-oxosilphinene was achieved stereoselectively in five steps from the known enone.
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Michiharu Kato, Bernhard Vogler, Youichi Tooyama, Akira Yoshikoshi
1990 Volume 19 Issue 1 Pages
151-154
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(1
R,5
S)-3-Phenylsulfenyl-6,6-dimethylbicyclo[3.1.1]heptanone obtained from (+)-nopinone was transformed into (1
R,4
S,5
S)-4-methyl-4-vinylbicyclo[3.1.1]heptan-2-one, whose cyclobutane ring was cleaved with BF
3·EtO
2–Zn(OAc)
2 in acetic anhydride to provide (4
S,5
S)-1-acetoxy-4-isopropenyl-5-methyl-5-vinyl-1-cyclohexene (
5), the key intermediate, in a highly regio- and stereoselective manner. Regioselective introduction of a three-carbon unit to
5 with acetone followed by dehydration yielded (+)-β-elemenone.
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Satoshi Takeda, Yasuhiro Iimura, Kazunori Tanaka, Etsuro Kurosawa, Ter ...
1990 Volume 19 Issue 1 Pages
155-156
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A new sesquiterpene alcohol has been isolated as a racemate from the title alga. The absolute structure of each enantiomer resolved by means of HPLC using chiral supports, was determined by the correlation with the synthetic intermediate, whose absolute structure was established by X-ray crystallographic analysis.
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Yutaka Ukaji, Akifumi Yoshida, Tamotsu Fujisawa
1990 Volume 19 Issue 1 Pages
157-160
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Synchronous insertion of alkyl group and deoxygenation reaction were achieved from α,β-epoxy silanes by the treatment with organolithium or organolanthanoid reagents in a regio- and stereoselective manner, i.e., the reaction of (
Z)-α,β-epoxy silanes gave the corresponding alkylated (
Z)-vinylsilanes, and (
E)-α,β-epoxy silanes were transformed into desilylated alkylated (
E)-olefins.
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Koichi Homma, Teruaki Mukaiyama
1990 Volume 19 Issue 1 Pages
161-164
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In the presence of a catalytic amount of trityl hexachloroantimonate, 2-trichloromethyl-1,3-dioxan-4-ones (
1) , easily prepared from β-hydroxycarboxylic acids, are stereoselectively attacked by
t-butyldimethylsiloxy-1-ethoxyethene to afford 1,3-dioxan-4-acetic acid derivatives. The stereoselectivity is dependent on both the substituent at the 5-position of
1 and the amount of the catalyst.
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Yuichi Ishikawa, Taisei Nishimi, Toyoki Kunitake
1990 Volume 19 Issue 1 Pages
165-168
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Single-chain ammonium amphiphiles which contain the salicylideneaniline unit formed stable bilayer membranes in water. The component orientation is either parallel or tilted depending on the alkyl chain length, as inferred from X-ray diffraction patterns and absorption spectral shifts.
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Yasuhiro Ikeura, Yoshihiro Honda, Kazue Kurihara, Toyoki Kunitake
1990 Volume 19 Issue 1 Pages
169-172
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Monolayer formation of octadecyl derivatives of a cyclohexanetricarboxylic acid (Kemp’s acid) was examined. A symmetrically substituted double-chain derivative gave a stable monolayer in which carboxylic acids formed cyclic dimers at the air-water interface.
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