bluuebunny/crossref_metadata_2025_split huggingface dataset:
Asymmetric Oxyselenenylation of Olefins Using Optically Active Selenobinaphthyls and d-Menthol as a Nucleophile
Authors: Fujita Ken-ichi , Iwaoka Michio , Tomoda Shuji 
Published: March 2006

Abstract
In order to improve the diastereomeric excess (d.e.) in asymmetric oxyselenenylation of symmetrical cis-olefins using bis [(R)-2′-acetylamino-1,1′-binaphthalene)-2-yl] diselenide, the use of d- and l-menthol was examined as nucleophiles. The d.e. was further enhanced for symmetrical cis-olefins as well as trans-β-methylstyrene by using d-menthol due to double stereodifferentiation between the (R)-binaphthyl and d-menthol.
Anti-Syn Isomerization of Carbazole-3-carbaldehyde Hydrazone Derivative. Isolation and Characteristics of Syn Isomer
Authors: Nakazawa Toru , Mizuta Yasufumi , Kawahara Akihiko , Miyamoto Eiichi , Muto Nariaki 
Published: March 2006

Abstract
9-Isopropylcarbazole-3-carbaldehyde diphenylhydrazone (anti-form) isomerized to syn-form upon UV light irradiation both in solution and in solid polymer film. The syn-form was successfully isolated in crystalline state by extracting with hexane and recrystallization.
Photochemical Conversion of anti-9-Methylcarbazole-3-carbaldehyde Diphenylhydrazone to Its syn-Isomer and an Indazole
Authors: Matsuda Eri , Aoto Mikiko , Takahashi Shichiro , Ono Hitoshi , Tokumaru Katsumi 
Published: March 2006

Abstract
Under irradiation, the compound in the title, which is frequently used as a charge transport material in electrophotography, undergoes reversible isomerization into its syn-isomer and cyclization to the corresponding indazole. These reactions will affect the characteristics in the practical electrophotographic process using this compound.
Diastereoselective Cyclocondensation Reaction of 3-Formyl-2-isoxazolines
Authors: Kamimura Akio , Kakehi Akikazu 
Published: March 2006

Abstract
The cyclocondensation reaction of 3-formyl-2-isoxazolines proceeds smoothly under the Lewis acid catalyzed conditions to give dihydropyran derivatives in moderate to high yields. Both diastereoisomers of the dihydropyrans, syn and anti, are prepared stereoselectively in the presence of an appropriate Lewis acid and solvent.
Iron(III) Complex Catalyzed Nitrosation of Terminal and 1,2-Disubstituted Olefins with Butyl Nitrite and Phenylsilane
Authors: Kato Koji , Mukaiyama Teruaki 
Published: March 2006

Abstract
In the presence of a catalytic amount of tris(1,3-diketonato)iron(III) complex, various terminal and 1,2-disubstituted olefins are converted into the corresponding nitroso alkane dimers in fairly good yields on treatment with phenylsilane and butyl nitrite at room temperature.
Transition Metal Catalyzed Acetic Acid Synthesis from Methane and CO
Authors: Nishiguchi Takahiro , Nakata Kazuyuki , Takaki Ken , Fujiwara Yuzo 
Published: March 2006

Abstract
Methane reacts with CO to give acetic acid in good yield by the CuSO4 and/or Pd(OCOEt)2 catalysts via C-H bond activation. This reaction has an advantage over the method which uses methanol and rhodium catalysts, in that cheap methane and copper catalysts can be used. Propane also reacts with CO to give butyric acids.
Promotion of V-P Oxide Catalyst for Butane Oxidation by Metal Additives
Authors: Tamaki Jun , Morishita Takehiro , Morishige Hidetaka , Miura Norio , Yamazoe Noboru 
Published: March 2006

Abstract
Mixed oxide catalyst V-P-O for the butane oxidation to maleic anhydride was significantly promoted by the addition of some metal cations. In particular, the addition of a small amount of Bi (Bi/V = 0.02) was the most effective. Over the Bi-added catalyst, the MA selectivity exceeded 70 mol% up to the butane conversion level of 88 mol%, attaining the maximum MA yield of 62 mol% at 395 °C.
Intermediates from Low-Temperature Photolysis of 4,4′-Diazidobiphenyl in Rigid Matrices
Authors: Ohana Tsuguyori , Kaise Masahiro , Yabe Akira 
Published: March 2006

Abstract
The photolysis of 4,4′-diazidobiphenyl (1) in an Ar matrix at low-temperatures (15–20 K) was investigated by UV-vis and IR spectroscopies. The dinitrene was identified as an intermediate by using 15N-labeled 1 and by trapping of the nitrene with CO. The presence of didehydroazepine and quinonoid structures was excluded.
Stereoselective Synthesis of 1,2-cis-Arabinofuranosides Using a New Titanium Catalyst
Authors: Mukaiyama Teruaki , Yamada Masaaki , Suda Shinji , Yokomizo Yoshihiro , Kobayashi Shu 
Published: March 2006

Abstract
In the presence of catalytic amounts of [1,2-benzenediolato(2-)-O,O′]oxotitanium and trimethylsilyl triflate, 1-O-trimethylsilyl-2,3,5-tri-O-benzyl-D-arabinofuranose stereoselectively reacts with various trimethylsilyl ethers to afford the corresponding 1,2-cis-arabinofuranosides in high yields.
Regioselective Photocyclodimerization of Cyclohexenones Intercalated on Clay Layers
Authors: Usami Hisanao , Takagi Katsuhiko , Sawaki Yasuhiko 
Published: March 2006

Abstract
UV light irradiation of 2-cyclohexenones (1) in the presence of saponite clay resulted in a regioselective photodimerization affording anti-head-to-head dimer. The directed intercalation of 1 was suggested by the regioselective dimerization, X-ray diffraction, IR and photoluminesence analyses.
Remarkable Stereochemical Features of Ene Reaction of 2-(Alkylthio)crotyl Silyl Ethers Proposal of a Six-Membered Chair-like Transition State
Authors: Nakamura Takashi , Tanino Keiji , Kuwajima Isao 
Published: March 2006

Abstract
In the presence of Lewis acid 2-(alkylthio)crotyl silyl ethers(1) react with aldehydes to give anti or syn adducts with high selectivity, depending on the geometry of 1. Further, on using TiCl4. E-adducts are produced, whereas Z selectivity is observed in the other Lewis acid promoted reactions.
First Evidence of the Effect of Chirality around the Octahedral Metal Center on the Aggregation Behavior of an Amphiphilic Cobalt(III) Complex
Authors: Yashiro Morio , Matsumoto Katsuya , Yoshikawa Sadao 
Published: March 2006

Abstract
Mixed ligand amphiphilic cobalt(III) complexes containing N-dodecylethylenediamine and a chiral tetraamine provide a novel example that the chirality around the octahedral metal center affects the aggregation behavior of the complexes.
ZnBr2-catalyzed Stereospecific 1,4-Elimination of 1-Methoxymethyl-2-(trimethylsilylmethyl)cyclobutanes. Stereoselective Preparation of 1,1,5-Trisubstituted (E)- and (Z)-1,5-Dienes
Authors: Fujiwara Tooru , Suda Atsushi , Takeda Takeshi 
Published: March 2006

Abstract
The stereoselective addition of alkylmetals to 2-(trimethylsilylmethyl)-1-cyclobutyl ketones and the ZnBr2-catalyzed stereospecific ring-opening reaction of resulting 1-methoxymethyl-2-(trimethylsilylmethyl)cyclobutanes gave 1,1,5-trisubstituted 1,5-dienes with high stereoselectivity.
A Novel Thermo-Sensitive Polymer. Poly(2-iso-propyl-2-oxazoline)
Authors: Uyama Hiroshi , Kobayashi Shiro 
Published: March 2006

Abstract
Poly(2-iso-propyl-2-oxazoline) (PiPrOZO), prepared by cationic ring-opening polymerization of iPrOZO, has been found to be a thermo-sensitive polymer. PiPrOZO possesses a cloud point (CP) around 36 °C. The CP changed by the addition of sodium chloride or a surfactant. For utilizing these characteristics, a new hydrogel was prepared by copolymerization of a PiPrOZO macromonomer with ethylene glycol dimethacrylate. The hydrogel swelled below the CP of PiPrOZO. Above the CP, on the other hand, the degree of swelling of the gel was very low.
Synthesis of Optically Active α-Alkylidene-β-hydroxy-γ-methylenebutyrolactones. Isoobtusilactones and Isomahubalactones (Isomahubanolide and Isomahubenolide)
Authors: Nokami Junzo , Ohtsuki Hirotoshi , Sakamoto Yasuhiko , Mitsuoka Masayuki , Kunieda Norio 
Published: March 2006

Abstract
The title compounds were prepared via stereoselective aldol reaction of α,β-unsaturated carboxylate α-anion equivalent, derived from optically active α-(arylsulfinyl)carboxylate and bromomagnesium diisopropylamide, with propargyl aldehyde as a key step.
The Effect of Cation on Kinetic Properties of Chloroaluminate Anions. 27Al NMR in Dialkylimidazolium Chloride-AlCl3 and LiCl-AlCl3 Melts
Authors: Ichikawa Kazuhiko , Izumi Mitsunori , Jin Takashi , Matsumoto Toshiyuki 
Published: March 2006

Abstract
We have carried out the 27Al NMR measurements of spectra and logitudinal magnetization recovery curves for 1-methyl-3-butylimidzolium chloride (DIMCl)-AlCl3 at 65 ± 1 mol% AlCl3 and LiCl-AlCl3 melt at 63 ± 1 mol% AlCl3. The lifetime of Al2Cl7−, τA, increases with increasing the size of cations from Li+, Py+ (butylpyridinium cation) to DIM+.
A Novel Synthesis of 3-Thietanols by Reactions of 2-(1-Haloalkyl)oxiranes with Monothiocarbamic Acid Salts
Authors: Karikomi Michinori , Narabu Shin-ichi , Yoshida Masaaki , Toda Takashi 
Published: March 2006

Abstract
Several 3-thietanol derivatives were synthesized in good yields by stereospecific reactions of 2-(1-haloalkyl)oxiranes with monothiocarbamic acid salts.
Preparation of Surface-modified CdS Microcrystallites. Enhancement of Solubility in Alcohols by Capping with Pentafluorothiophenol
Authors: Ogata Tomoyuki , Hosokawa Hiroji , Oshiro Tatsuhiko , Wada Yuji , Sakata Takao , Mori Hirotaro , Yanagida Shozo 
Published: March 2006

Abstract
Pentafluorophenyl-capped CdS microcrystallites (av. 3–6 nm in diameter) are prepared and characterized by TEM and 19F NMR spectroscopy. Although the similarly prepared phenyl-capped CdS microcrystallites is insoluble in alcohols, the capping with perfluorinated phenyl groups induces high solubility in methanol and ethanol.
Transient Resonance Raman Spectra of Michler’s Ketone in the Lowest Excited Triplet State
Authors: Tahara Tahei , Hamaguchi Hiro-o 
Published: March 2006

Abstract
Transient resonance Raman spectra of Michler’s ketone in the lowest excited triplet state were measured in ethanol and benzene. The spectral features of the T1 state in these solvents were similar to each other although some frequency shifts were observed. This result suggests that Michler’s ketone retains a charge transfer T1 state in nonpolar solvents as well as in polar solvents.
Synthesis of [d-Pyrenylalanine4,4′]gramicidin S by Solid-Phase-Synthesis and Cyclization-Cleavage Method with Oxime Resin
Authors: Xu Ming , Nishino Norikazu , Mihara Hisakazu , Fujimoto Tsutomu , Izumiya Nobuo 
Published: March 2006

Abstract
Cyclic decapeptide [d-pyrenylalanine4,4′]gramicidin S has been efficiently synthesized via stepwise solid-phase-synthesis and cyclization-cleavage with the Kaiser’s oxime resin in 45% total yield. This analog showed the similar conformation to the natural gramicidin S in MeOH. The pyrene ring introduced into the peptide is a useful fluorescent probe for the study of the mechanism of the antimicrobial activity.
A New Stereocontrolled Route to trans-2,5-Disubstituted Tetrahydrofurans
Authors: Chikashita Hidenori , Yasuda Hiroyuki , Kimura Yasunori , Itoh Kazuyoshi 
Published: March 2006

Abstract
An effective new route for the stereocontrolled synthesis of trans-2,5-disubstituted tetrahydrofurans was described, which involved a new type of 1,4-asymmetric induction based on the addition of originally designed dithianyl anion to aldehydes and a stereocontrolled cyclodehydration of the resulting 1,4-diols.
Mechanochemical Reaction of Poly(Vinyl Alcohol) Gels Due to Cooperative Effects of Crosslinks – Respondences to pH and Glucose
Authors: Yonese Masakatsu , Baba Kazuhiko , Kondo Masatoshi , Kishimoto Hiroshi 
Published: March 2006

Abstract
In aqueous solution of borates, poly(vinyl alcohol) (PVA) hydrogels prepared by a freeze-drying method showed reversible changes of tensile forces responding to pH and the concentra tions of glucose Cglu. Linear relationships between the stress changes and Cglu were confirmed in the region Cglu &gt; 0.2 mmol/dm3.
Group 5A Metal Oxides as Promoters for Oxidative Coupling of Methane
Authors: Yamamura Masami , Okado Hideo , Tsuzuki Naohide 
Published: March 2006

Abstract
Group 5A metal oxides were tested as promoters for oxidative coupling of methane. They were effective promoters for the coupling reaction, when mixed with 1A, 1A/2A, and 1A/3A oxide catalysts, respectively. Addition of Group 5A metal increased the activity of these catalysts.
The Reaction of Nitrogen Dioxide with N-Benzylidene-t-butylamine N-Oxide. Formation of a White Solid Adduct and Its Properties
Authors: Sonokawa Koji , Machida Hidenori , Sakakibara Kazuhisa , Hirota Minoru 
Published: March 2006

Abstract
The reaction of N-benzylidene-t-butylamine N-oxide (PBN) with NO2 gave white diamagnetic solid C11H16N2O4 in addition to greenish blue free radical species. The white solid was shown to decompose quantitatively into the starting PBN and nitric acid when it was dissolved in water.
Silica-Supported MoO3 Catalyst Prepared by Alkoxide Method
Authors: Kobayashi Junya , Shimizu Takashi , Inamura Kazuhiro 
Published: March 2006

Abstract
Highly dispersed silica-supported molybdenum catalysts were prepared by an alkoxide method, using ethylsilicate and ammonium paramolybdate dissolved in ethylene glycol. By comparing temperature-programmed sulfiding(TPS) spectra of the catalysts with those of alumina or silica-supported catalysts formed by an impregnation method, the structures and the dispersion states of molybdenum oxide in the catalysts prepared by the alkoxide method were discussed.
The Energy Aspects of Oil/Water Partition. Proposition of Novel Hydrophobia Parameters for the Treatment of Quantitative Structure-Activity Relationships
Authors: Fujiwara Hideaki , Da Yong-Zhong , Ito Katsuhiko 
Published: March 2006

Abstract
Conventional hydrophobia parameter logP, decimal logarithm of partition coefficient, has been separated into the corresponding terms of enthalpy and entropy. These novel terms are determined for various alcohols and benzoic acids, and shown to give promising results in the analysis of quantitative structure-activity relationships.
Determination of the Mode of Hydrolysis of Chitooligosaccharides by Chitosanase Derived from Aspergillus Orvzae by Thin Layer Chromatography
Authors: Kimura Kumi , Murota Akihiko , Yoshihiro Yoshiro 
Published: March 2006

Abstract
We found that the enzyme from rice-koji of Aspergillus oryzae removed single glucosamine residue from a sequence of β-(1-4)-linked glucosamine chain, such as chitosan and glucosamine oligosaccharides. It became clear that the N-acetyl-β-d-glucosaminidase of Aspergillus orvzae was characterized as an exo-β-d-glucosaminidase.
Convenient Preparation of (Chlorodifluoromethyl)arenes. Useful Precursors for Aryldifluoromethyl Radicals
Authors: Yoshida Masato , Morinaga Yoshihiro , Ueda Masaaki , Kamigata Nobumasa , Iyoda Masahiko 
Published: March 2006

Abstract
Chlorodifluoromethyl group was introduced into aromatic rings using bis(chlorodifluoroacetyl) peroxide which was readily prepared from corresponding acid anhydride with 30% hydrogen peroxide, and the chlorine was successively replaced by hydrogen or allyl group in excellent yields under radical conditions.
Ready Preparation of Trialkoxyboranes and Dialkoxyboranes by LiBEt3H-Promoted Reaction of BH3 in Tetrahydrofuran with Alcohols
Authors: Masuda Yuzuru , Nunokawa Yutaka , Hoshi Masayuki , Arase Akira 
Published: March 2006

Abstract
A catalytic amount of LiBEt3H (1%) promoted markedly the reactions of BH3 in tetrahydrofuran (THF) with stoichiometric amounts of alcohols (1:2 and 1:3) to provide corresponding trialkoxyboranes and dialkoxyboranes quantitatively under mild reaction conditions.
Directed ortho Lithiation in the Reactions of 3,5-Dimethyl- and 5-Trifluoromethyl-1-phenylpyrazoles with Butyllithium
Authors: Iwata Satoru , Qian Cheng-Ping , Tanaka Kiyoshi 
Published: March 2006

Abstract
Lithiation of 3,5-dimethyl- and 5-trifluoromethyl-1-phenylpyrazoles with butyllithium is found to be directed to an ortho position. The ortho direction is ascribed to coordination of lithium with pyrazole 2-nitrogen or 5-trifluoromethyl group, respectively.
Photochemistry of 1,2,3-Benzotriazin-4-one in Matrices. A New Photochromic System Including Triazinone-Azoazetinone Photointerconvertion
Authors: Tomioka Hideo , Komatsu Kazunori 
Published: March 2006

Abstract
Irradiation (λ &gt; 300 nm) of 3-methoxy-1,2,3-benzotriazin-4-one (3) matrix isolated in Ar at 10 K resulted in the formation of E- and Z-1-(methoxyazo)benzazetinones which reproduced 3 upon irradiation of light of λ &gt; 350 nm, thus constituting a new photochromic system consisting of ternary components.
Electron Spin Resonance of the Quartet State of 1,3,5-Tris(diphenylamino)benzene
Authors: Yoshizawa Kazunari , Chano Akihisa , Ito Akihiro , Tanaka Kazuyoshi , Yamabe Tokio , Fujita Hideo , Yamauchi Jun 
Published: March 2006

Abstract
The electron spin resonance (ESR) of the quartet state of 1,3,5-tris(diphenylamino)benzene (TDAB) is reported. The orange-colored cationic radical is prepared by oxidation of TDAB with trifluoroacetic anhydride in a tetrabutylammonium tetrafluoroborate-CH2Cl2 solution. The ESR spectrum reveals that the cationic radical shows a typical quartet signal and that it is extremely stable at room temperature.
A New Picket-Fence Porphyrin Precursor. Synthesis and Atropisomerism of Free Base and Zinc Complex of meso-Tetra(o-methoxycarbonylphenyl)porphyrin
Authors: Fujimoto Tsutomu , Umekawa Hideki , Nishino Norikazu 
Published: March 2006

Abstract
A new “picket-fence” porphyrin precursor with carboxy terminal groups has been prepared. Four atropisomers of meso-tetra(o-methoxycarbonylphenyl)porphyrin have been separated by chromatography. The conformational stability of the αααα-isomer was examined to the prolonged heating for both free base and zinc complex. The usefulness of meso-tetra(o-carbonylphenyl)porphyrin appeared to be not at all inferior to well-known meso-tetra(o-aminophenyl)porphyrin.
An Efficient Method for the Preparation of Chiral Synthons Starting from Racemic Compounds by Way of Asymmetric Synthesis
Authors: Kobayashi Shu , Shiina Isamu , Izumi Jun , Mukaiyama Teruaki 
Published: March 2006

Abstract
Optically active α-alkoxy-α-methyl-β-hydroxy ester derivatives are prepared starting from racemic α-alkoxy propionic acid ester derivatives by way of asymmetric aldol reaction of the corresponding achiral intermediates. (−)-2-C-Methyl-D-threono-1,4-lactone is conveniently synthesized by using this methodology.
1H NMR Study of the Reaction of Iron(III) Porphyrins with NaBH4 in the Presence of Alkenes. Formation of Organoiron(III) Porphyrins
Authors: Setsune Jun-ichiro , Ishimaru Yoshihiro , Sera Akira 
Published: March 2006

Abstract
The treatment of [(tpp)FeIIICl] [tpp = tetraphenylporphyrin dianion] with NaBH4 in the presence of alkenes afforded σ-type organoiron(III) porphyrins, the structure of which was analyzed by paramagnetic 1H NMR. While 1-alkenes were hydrometallated to give σ-(1-methylalkyl)FeIII(tpp) along with a small amount of σ-(alkyl)FeIII(tpp), 2- and 3-alkenes yielded σ-(1-methylalkyl)FeIII(tpp) complexes without any regioisomers.
Lithium-Chlorine Exchange Reaction of α-Chloro α-Sulfonyl Ketones
Authors: Satoh Tsuyoshi , Shishikura Jun-ichi , Hayashi Yasumasa , Yamakawa Koji 
Published: March 2006

Abstract
Lithium-chlorine exchange of α-chloro α-sulfonyl ketones, easily prepared from 1-chloroalkyl aryl sulfoxides and aldehydes in good yields, with n-butyllithium gave α-sulfonyl ketones in high yields. Some trials to trap the enolate intermediate were carried out.
CO2 Hydrogenation over Carbide Catalysts
Authors: Dubois Jean-Luc , Sayama Kazuhiro , Arakawa Hironori 
Published: March 2006

Abstract
Carbides such as Mo2C, Fe3C, and WC have proved to be effective catalysts for hydrogenation of CO2. Mo2C and Fe3C showed high CO2 conversion and good methanol selectivity at 220 °C. A considerable amount of dimethylether was produced over WC. TaC and SiC were almost inactive. Copper promoted carbide catalysts were also tested for CO2 hydrogenation.
Mutual Separation Characteristics for Lanthanoid Elements via Gas Phase Complexes with Alkaline Chlorides
Authors: Adachi Gin-ya , Murase Kuniaki , Shinozaki Kiyoshi , Machida Ken-ichi 
Published: March 2006

Abstract
Mutual separation characteristics of lanthanoid chlorides LnCl3 (Ln = Pr, Nd) using a chemical vapor transporting method via gaseous complexes were investigated. Compared with AlCl3 as the transporting agent, alkaline chlorides can transport more amounts of LnCl3, and enhance the separation efficiency between PrCl3 and NdCl3.
Theoretical Consideration on Photochromism of an Oxide Doped with Transition-Metal Ions in Strong Electric Field
Authors: Kobayashi Kenkichiro , Matsushima Shigenori , Okada Genji 
Published: March 2006

Abstract
We propose a new principle of an optical memory using photoionization of transition-metal ions doped into an oxide which is kept in strong electric field. Several conditions required to realize an optical memory are present.
Synthesis of Medium Ring 1,5-Dienes
Authors: Usui Shuji , Haino Takeharu , Hayashibara Tatsuhiko , Hirai Yoshimasa , Fukazawa Yoshimasa , Kodama Mitsuaki 
Published: March 2006

Abstract
Medium ring compounds (9 to 11 membered rings) having endo (E or Z) and exo double bonds at 1,5-positions were synthesized by intramolecular cyclization of the ω-functionalyzed allylic anion stabilized by a sulfur atom. The yields of cyclization were related not only with the cyclization enthalpy (steric strain of the resultant cyclic compounds) but also with entropy factor.
Synthesis and Surface Properties of Perfluoro-oxa-alkylated Oligomers
Authors: Sawada Hideo , Gong Yue-Fa , Matsumoto Takeo , Kosugi Masanori , Migita Toshihiko 
Published: March 2006

Abstract
New perfluoro-oxa-alkylated oligomers were obtained by the reactions of methacrylate monomers with perfluoro-oxa-alkanoyl peroxides under very mild conditions, and the perfluoro-oxa-alkylated oligomers containing hydroxyl ethylene oxide units were found to indicate surface properties typical of the amphipathic compounds.
Reaction of Chalcone Derivatives with Aromatic Aldehydes Promoted by Ytterbium Metal
Authors: Takaki Ken , Beppu Fumikazu , Nakagawa Ikuko , Fujiwara Yuzo 
Published: March 2006

Abstract
Ytterbium metal promoted reaction of chalcone with equimolar amount of benzaldehyde gave 2-benzoyl-5-phenylhydroxymethyl-1,3,4-triphenylcyclopentanol, whereas 2,5-bis(benzoyl)cyclopentanol was obtained by the reaction with excess amount of the aldehyde. In addition, similar reaction of 3-anisyl-1-phenyl-2-propen-1-one with anisaldehyde afforded 2:2 adduct, 5-[anisyl(anisylmethoxy)methyl]cyclopentanol, irrespective of amount of the aldehyde.
Acid Dissociation and Activation Parameters for Ring Inversion of Diaminocalix[4]arene
Authors: Araki Koji , Murakami Hiroto , Ohseto Fumio , Shinkai Seiji 
Published: March 2006

Abstract
pKa Values and activation parameters for ring inversion of 25,27-diamino-5,11,17,23-tetra-t-butylcalix[4]arene-26,28-diol were estimated. It was found that in the OH groups of this compound the “super-acidic” proton, observed for conventional calix[4]arene-25,26,27,28-tetrols, no longer exists and ring inversion occurs more easily.
α-Hydrazono-β-keto Esters as Command Molecules
Authors: Yamamura Shigeo , Tamaki Takashi , Seki Takahiro , Sakuragi Masako , Kawanishi Yuji , Ichimura Kunihiro 
Published: March 2006

Abstract
The nematic director alignment in the liquid crystal cell was reversibly regulated by geometrical isomerization of α-hydrazono-β-keto ester derivatives directly linked on the substrate surface. The reversible change in the shape of the photochromic molecules may be responsible for regulating the alignment of the nematic liquid crystals.
A Novel Type of Chiral Diphosphine Ligand, trans-2,3-Bis(diphenylphosphino)-1-methyl-1-cyclopropanecarboxylic Acid and Asymmetric Allylic Alkylation by the Use of Its Palladium Complex
Authors: Okada Yoshiharu , Minami Toru , Yamamoto Tsutomu , Ichikawa Junji 
Published: March 2006

Abstract
Optically active trans-2,3-bis(diphenylphosphino)-1-methyl-1-cyclopropanecarboxylic acid was synthesized from trans-1,2-bis(diphenylphosphinyl)ethene via resolution of the racemic diphosphine oxide. Asymmetric allylic alkylation of 2-cyclohexenyl acetate with l-menthyl sodiodiethylphosphonoacetate was achieved in good optical yields by the use of its palladium complex.