bluuebunny/crossref_metadata_2025_split huggingface dataset:
Addition Reaction of Carboxylic Anhydrides to the Carbon-Nitrogen Double Bond of Unsubstituted Cyclic Imidates
Authors: Kobayashi Shiro , Isobe Michihisa , Saegusa Takeo 
Published: July 2006

Abstract
Acyclic and cyclic (SAn and GAn) carboxylic anhydrides were added at room temperature to the C=N bond of unsubstituted cyclic imidates of 2-oxazoline (OZO) and 5,6-dihydro-4H-1,3-oxazine (OZI) to give addition products quantitatively. In contrast to these findings, the reactions of acetyl halides with OZO and OZI yielded ringopened products and the reactions of carboxylic anhydrides with 2-benzyl-2-oxazoline (BzOZO) afforded also the ring-opened products. The bicyclic addition product of OZO with SAn is equilibrated with a mixture of starting materials. The stereochemistry of addition products having a six-membered ring system is discussed.
Effects of Chelating Agents on the Preparation of Benzenediols by Oxidation of Phenol with Peracetic Acid
Authors: Tsuchiya Tohru , Ikehira Kazuhiro , Imamura Juichi 
Published: July 2006

Abstract
The oxidation of phenol with peracetic acid has been investigated in connection with the industrial preparation of benzenediols. The effects of 25 additives, such as derivatives of monomeric and condensed phosphoric acid, chelating agents, and salts of polybasic carboxylic acids, were examined; derivatives of condensed phosphoric acid were found to be most effective. The oxidation of phenol (213 mmol) with peracetic acid (21 mmol) in the absence of the additives gave 1,2- and 1,4-benzenediols in only 5.8% and 7.6% yields, respectively. But in the presence of 2.0×10−7 mol of potassium diphosphate the yields of 1,2- and 1,4-benzenediol were 47% and 31%, respectively. The improvement in the yields by the additives is attributable to the masking of a trace of metals, especially iron and cobalt, present in the reaction mixture. These metals tend to catalyze the further oxidation of the benzenediols formed.
Liquid-phase Oxidation of Anthracene in Acetic Acid by Use of Copper(II) Chlorocomplexes. II. Kinetic Study
Authors: Koshitani Jinya , Kado Toshio , Ueno Yoshio , Yoshida Takatoshi 
Published: July 2006

Abstract
A kinetic study was performed on the oxidation of anthracene by use of copper(II) chlorocomplexes, which were produced in reactions of copper(II) acetate with lithium chloride in acetic acid. When the pressure of oxygen was high enough that the rate of oxidation was not affected, the result was as follows:
−\fracdO2dt∝[RH]1[Cu2(OAc)4]01⁄2[LiCl]01⁄2−0.
Akineticapproximationtotheexperimentalresultwasattempted.
Application of Regular Solution Theory to Extraction of Salicylaldehyde Oxime Chelates
Authors: Narayanan S , Rao G N 
Published: July 2006

Abstract
The distribution coefficients of salicylaldehyde oxime and its metal chelates, namely of Co(II), Cu(II), and Zn(II) were determined between aqueous acetate phase (μ=0.1) and eight ‘inert’ organic solvents at 25 °C. On the basis of regular solution theory, the correlation between the distribution coefficients of the ligand (PHA) and that of the metal chelates (PM) expressed by logPM=nlogPHA+ const, was shown to be valid satisfactorily in most of the systems. Hexane and cyclohexane showed abnormal behaviour in extraction with Cu(II), while with Zn(II) extraction to the desired level was not possible with these two solvents. A good correlation was also observed between the distribution coefficient of salicylaldehyde oxime and the ‘solubility parameter’ of the solvents and the solutions are shown to be regular.
The Gibbs Free Energy of the Formation of the Al(OH)4− Ion at Elevated Temperatures
Authors: Chang Byong-Tae 
Published: July 2006

Abstract
The Gibbs free energy of the formation of the Al(OH)4− ion, ΔGf°[Al(OH)4−], has been determined from the solubility data of alumina hydrates at temperatures up to 300 °C. According to the results of thermodynamical calculations, ΔGf°[Al(OH)4−] is −1305.3 kJ/mol at 25 °C, and it decreases almost linearly with an increase in the temperature. Its temperature dependence between 25 and 300 °C can be expressed as follows: ΔGf°[Al(OH)4−]=−1152.7–3.318T−5.64×10−4T2+1.202TlogT.
Isotope Effect on Hydrogen Atom Abstraction Reaction by Recoil T Atoms in Solid n-C10D22–n-C10H22 Mixtures. Comparison of Recoil T Atoms with D Atoms in γ-Radiolysis
Authors: Aratono Yasuyuki , Taghikawa Enzo , Miyazaki Tetsuo , Fueki Kenji 
Published: July 2006

Abstract
An isotope effect on the hydrogen atom abstraction reaction by recoil T atoms in the n-C10D22–n-C10H22 mixtures in the solid phase is compared with the reaction by D atoms in the γ-radiolysis. A small isotope effect for the recoil T atoms is explained by a track model.
Selective Transport of Potassium Ions against Their Concentration Gradient by Pentaethylene Glycol Derivative Containing Both 8-Quinolyl and o-Carboxylphenyl Terminal Groups
Authors: Hiratani Kazuhisa 
Published: July 2006

Abstract
A pentaethylene glycol derivative containing both 8-quinolyl and o-carboxylphenyl terminal groups can transport potassium ions selectively against the concentration gradient in liquid membrane systems containing more than one alkali ion species in aqueous solution. Uptake of cations by this synthetic ionophore from the aqueous solution into the organic layer is confirmed to be important for exhibiting this excellent selectivity toward potassium ions.
Extraction of Lead(II) in Aqueous Halide-Perchlorate Solutions with Trioctylphosphine Oxide in Hexane
Authors: Kusakabe Satoshi , Sekine Tatsuya 
Published: July 2006

Abstract
The stability and the extractability with trioctylphosphine oxide(L) in hexane of lead(II) halide complexes in 1 mol dm−3 Na(ClO4) were studied. The complexes were stable and more extractable in the following order of the ligands: Cl−&lt;Br−&lt;I−. The maximum numbers of the ligand (n) in the complexes PbXn2−n were 2(Cl−), 3 (Br−), and 4 (I−). The chemical forms of the extracted species with L were in all cases Pb(ClO4)2L2, PbX(ClO4)L3, and PbX2L2.
Preparation and Molecular Structure of cis-Diaqua[(7S, 14S)-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclo-tetradecane]nickel(II) Chloride
Authors: Ito Haruko , Sugimoto Masako , Ito Tasuku 
Published: July 2006

Abstract
A six-coordinate diaqua nickel(II) complex with the title macrocyclic ligand, [Ni(H2O)2(S,S-L)]Cl2, has been synthesized and its structure has been determined by the X-ray analysis. Coordination geometry about the Ni is of cis-NiO2N4 type with the macrocyclic ligand folded.
Application of the Water-gas Shift Reaction. III. Reduction of Oxidized Nitrogen Compounds with CO and H2O Catalyzed by [Ru(cod)py4](BPh4)2
Authors: Okano Tamon , Fujiwara Kensuke , Konishi Hisatoshi , Kiji Jitsuo 
Published: July 2006

Abstract
The ruthenium(II) complex, [Ru(cod)py4](BPh4)2 (cod=1,5-cyclooctadiene, py=pyridine) has been shown to catalyze the reduction of oxidized nitrogen compounds with CO and H2O. In this reaction, primary, secondary, and tertiary nitroalkanes are converted into amides, ketones, and amines, respectively. Nitrosobenzene and picoline N-oxides are also reduciable to amines in good yields.
Stereoselective Micellar Catalysis. II. Kinetic Properties of Optically Active Micellar Catalysts for Cleavage of Amino Acid Ester Derivatives
Authors: Ihara Yasuji , Hosako Reiko 
Published: July 2006

Abstract
Stereoselective reactions of the enantiomers of N-acylamino acid p-nitrophenyl esters with N-decanoyl-(d or l)-histidine (DecHis) in an optically active surfactant (DMEBr) derived from (l)-ephedrine were studied at 25 °C and pH 7.30 in comparison with those of simple surfactant, hexadecyltrimethylammonium bromide (CTABr). The mixed micelles of DecHis and DMEBr are effective stereoselective catalysts and the catalytic effects are determined mainly by the nucleophilic reactivity of the optically active histidine residue of DecHis.
Adsorption of Ethylene Oxide on Cab–O–Sil Silica, Reactive Silica, and Oxygen-treated Reactive Silica
Authors: Sotani Noriyuki 
Published: July 2006

Abstract
Ethylene oxide reacted with surface Si–OH of Cab–O–Sil silica to form Si–O–CH2–CH2–OH, while ethylene oxide was adsorbed on the silicon radicals of the reactive silica, and the oxygen radicals of the oxygen-treated reactive silica on which the adsorbed species polymerized to form (–CH2–O–CH2–)n.
Molecular Structure of [2](2,5)(7,7,8,8-Tetracyanoquinodimethano)[2](1,4)naphthalenophane
Authors: Mizuma Takashi , Miki Kunio , Kai Yasushi , Tanaka Nobuo , Kasai Nobutami 
Published: July 2006

Abstract
Molecular structure of [2.2](1,4)naphthalenophane containing 7,7,8,8-tetracyanoquinodimethan moiety as an electron acceptor has been determined by means of X-ray diffraction. Crystals belong to monoclinic system, space group Cc with four molecules per unit-cell; a=9.770(1), b=15.176(2), c=13.299(2) Å, β=98.43(1)°. The structure was established by the direct method and refined by the full-matrix least-squares to R=0.035 for 1217 non-zero reflections. The [2.2]paracyclophane skeleton has the usual structure; a half of the naphthalene moiety has a boat-form, the six-membered ring of the TCNQ, moiety also has a boat-form, and two C(CN)2 portions in the TCNQ, moiety are bent out and slightly twisted from the six-membered ring. The other half of the naphthalene ring free from the bridging is planar and are slightly bent out from the [2.2]paracyclophane skeleton.
The Discrimination of the Oxidation States of Neptunium in Sodium Hydroxide Solutions by Means of Chromatography on Alumina
Authors: Shiokawa Yoshinobu , Yamana Hajimu , Sat\={o} Akiko , Suzuki Shin 
Published: July 2006

Abstract
A method of discriminating the oxidation states of Np in a NaOH solution by means of chromatography on alumina is proposed. In a NaOH solution of 0.5–1.7 M(1 M=1 mol dm−3), the separation of Np(VI) from Np(VII) can be made effectively by means of chromatography on alumina. Only a little Np(VI) is adsorbed on alumina the Np(VII) adsorbed to some extent, and the Np(V), strongly, under the same conditions. By applying this chromatographic method, the method of preparing Np(VI) and Np(VII) of a tracer quantity in 1 M NaOH is established.
Voltammetric Studies of the Use of the Rotated Oxide Electrode as an Indicator Electrode and as a View to the Determination of EDTA and Other Complexanes
Authors: Yoshimura Tadayosi 
Published: July 2006

Abstract
The accessible potential ranges of rotated lead dioxide (PbO2) and manganese dioxide (MnO2) electrodes were investigated in supporting electrolyte solutions of 0.1 mol/1 (mol/dm3) KNO3 at various pH values, by measuring the base currents of these oxide electrodes. The anodic and cathodic ascending potentials of both the oxide electrodes are pH-independent in a neutral solution. In each neutral system of KNO3, KClO4, K2SO4, and KCl, the accessible potential range of the PbO2 electrode was from +1.4 to +0.2 V vs. SCE, while that of the MnO2 electrode was from +1.2 to +0.3 V, and the lower manganese oxide electrode from +0.3 to −0.9 V. Furthermore, the applications of these electrodes to the determination of EDTA and other complexanes were examined. Both the oxide electrodes gave a good calibration curve which could establish a linear relationship to the EDTA concentration, passing through the point of origin. The rotated PbO2 and MnO2 electrodes seem to be useful for determining depolarizers such as the EDTA-type complxanes.
Kinetic Studies of the Oxidation of l-Ascorbic Acid by the Peroxodisulfate Ion, and of Copper(II)-catalysis
Authors: Kimura Masaru , Kobayashi Akiko , Boku Keiko 
Published: July 2006

Abstract
Kinetic studies of the oxidation reaction of l-ascorbic acid by the peroxodisulfate ion(S2O82−) are carried out in an aqueous solution over the pH range of 3.4–4.6 at various ionic-strengths from 0.071 to 1.07 M (1 M= 1 mol dm−3) with NaClO4, and at four temperatures between 15 and 30 °C, at an ionic-strength of 1.07 M. The variations in the rate of the oxidation with the hydrogen-ion concentrations are consistent with the reaction schemes involving two pH-related species; ascorbic acid H2A (k1=0.032 M−1 s−1 at 25 °C, ΔH1\eweq=17 kJ mol−1, ΔS1\eweq=−220 J deg−1 mol−1) and the ascorbic anion HA− (k2=0.43 M−1 s−1 at 25 °C, ΔH2\eweq=45 kJ mol−1, ΔS2\eweq=−102 J deg−1 mol−1). A relationship of logk2=−1.47+2.17I1⁄2⁄(1+I1⁄2) is found with the ionic-strength (I) at 25 °C. The reaction rate is greatly catalyzed by the presence of trace amounts of the copper(II) ion; the mechanisms of the copper(II)-catalyzed reaction are discussed.
Spectrophotometric Determination of Iron(III) after Separation by Adsorption of Its 5-Chloro-7-iodo-8-quinolinol Complex on Microcrystalline Naphthalene
Authors: Satake Masatada , Mehra Mool C , Fujinaga Taitiro 
Published: July 2006

Abstract
A procedure is described for the spectrophotometric determination of iron(III) at ppm levels with 5-chloro-7-iodo-8-quinolinol. Iron(III) reacts with the reagent in an acidic solution to form a water-insoluble blue-black complex, which can be quantitatively adsorbed on the surface of freshly precipitated microcrystalline naphthalene at room temperature. The separated iron(III) complex is dissolved in N,N-dimethylformamide, together with the naphthalene, and the absorbance of the resulting solution is measured at 480 nm. Beer’s law is obeyed over the range of 5–88 μg of iron in 10 ml of the solvent. The molar absorptivity of the complex was found to be 6.3×103 l mol−1 cm−1 at 480 nm. The effects of various factors, such as the pH, the amounts of the reagent and naphthalene, and diverse ions, were also examined. The proposed method was satisfactorily applied to the determination of iron in several selected samples, including standard reference materials, aluminum metal, and natural water.
Synthesis of dl-3-Hydroxycuparene by a Claisen Rearrangement of Allyl Aryl Ether
Authors: Inouye Yoshinobu , Inomata Satoru , Ishihara Yasumasa , Kakisawa Hiroshi 
Published: July 2006

Abstract
The Claisen rearrangement of 1-methyl-2-[(3-methylphenoxy)methyl]cyclopentene in N,N-dimethylformamide gave 5-methyl-2-(1-methyl-2-methylenecyclopentyl)phenol(5) via its trimethylsilyl ether. The methylation of 5, followed by a Simmons-Smith reaction and by the catalytic hydrogenolysis, afforded 3-hydroxycuparene.
Studies on the High-pressure Reaction of Rare-earth Sesquioxides with Vanadium Dioxide
Authors: Shin-ike Tsutomu , Adachi Gin-ya , Shiokawa Jiro , Shimada Masahiko , Koizumi Mitsue 
Published: July 2006

Abstract
The reaction of rare-earth sesquioxides (Ln2O3 with vanadium dioxide (VO2) at 1400 °C and 50 kbar and 30 kbar was studied. Quadrivalent vanadium ions were reduced to the trivalent state, rare-earth vanadates(III) (LnVO3) being obtained. For LnVO3 a typical transformation of the ABO3-type compounds, one from the aragonite-type to the perovskite-type via the vaterite- or calcite-type structure was observed with a decrease in the ionic radius of the rare-earth ions. The magnetic properties of the vaterite-type LnVO3 were studied.
A Kinetic Study of the Anation Reactions of Some Cobalt(III) Complexes Containing Macrocyclic Quadridentate Amine Ligands
Authors: Tsukahara Keiichi , Oshita Hiroshi , Emoto Yasunobu , Yamamoto Yasuo 
Published: July 2006

Abstract
The kinetics of the anation of trans-[Co(OH)(N4)(H2O)]2+ by acetate ions (OAc−) have been studied at 25 °C and at an ionic strength of 0.10 mol dm−3 (LiClO4), and over the pH range from 3.62 to 5.17; N4 represents a macrocyclic ligand. The reaction is considered to proceed through a dissociative mechanism. The rate constants of the loss of the coordinated water of [Co(OH)(N4)(H2O)]2+ are estimated to be (1.4±0.2)×10−2 s−1, (8.9±1.6)×10−2 s−1, (1.0±0.1)×10−1 s−1, and (4.0±0.1)×10−1 s−1 for [14]aneN4, Me6[14]4,11-dieneN4, ms-Me6[14]aneN4, and rac-Me6[14]aneN4 complexes respectively. These represent the steric acceleration by the methyl groups of the macrocyclic ligands. The anation of the [14]aneN4 complex by chloride and bromide ions in acetate-buffer solutions has also been investigated. The relative effectiveness of entering groups for the coordination to the pentacoordinate intermediate follows the order: H2O&lt;OAc−&lt;Cl−&lt;Br−. The substitution reaction of [Co(OH)(N4)(H2O)]2+ is slower than the ascorbate reduction of this complex reported previously. It is concluded that the electron-transfer reaction does not proceed through an inner-sphere mechanism, but through an OH-bridged mechanism.
Binuclear Metal Complexes. XLV. Synthesis and Magnetic, Spectral, and Electrochemical Studies of Strati-bis Copper(II) Complexes of Some Schiff Bases Derived from Primary Tetraamines and Salicylaldehydes
Authors: Izumitani Tatsuo , Nakamura Masaaki , Okawa Hisashi , Kida Sigeo 
Published: July 2006

Abstract
New Schiff base ligands, 1,2,3,4-tetrakis(R-salicylideneamino)-2,3-dimethylbutane (abbreviated as H4(R-sata); R (substituent on the ring)=H, 5-Me, 5-But) and 1,2-bis(R-salicylideneamino)-1,2-bis(salicylideneaminomethyl)cyclohexane (H4(R-sacta)), which are capable of forming “strati-bis” type binuclear copper(II) complexes, have been synthesized. Magnetic, spectral and electrochemical properties of the binuclear copper(II) complexes, Cu2(R-sata) and Cu2(R-sacta), were investigated in comparison with those of mononuclear copper(II) complexes Cu(R-salpn) and Cu(R-sacda), where H2(R-salpn) is N,N′-bis(R-salicylidene)-1,2-propanediamine and H2(R-sacda) 1-(R-salicylideneamino)-1-(R-salicylideneaminomethyl)cyclohexane. ESR spectra of Cu2(sata), Cu2(sacta) and Cu2(5-Me-sacta) showed a seven-lined hyperfine structure whose hyperfine coupling constant (A||≈85 G, 1 G=10−4 T) was about one half of that of the corresponding mononuclear copper(II) complex. Each electronic spectrum of these binuclear complexes showed the π-π* transition originated from the azomethine group at a low frequency compared with that of the corresponding mononuclear complex. Cyclic voltammograms of these three complexes involved two redox couples. The first redox couple attributable to the Cu(II, II)/Cu(II,I) process is higher in potential than the Cu(II)/Cu(I) process of the corresponding mononuclear complex. These characteristics were discussed in terms of the electron-delocalization through the π-π interaction between the two [CuN2O2]-chromophores.
C,O-Chelates of the Trifluoroacetylacetonate Dianion with Palladium(II). Molecular Structure of [Pd(tfac(2–)-C,O)(PPh3)(2,6-Me2-py)]
Authors: Okeya Seichi , Kawakita Yasuo , Matsumoto Shinichi , Nakamura Yukio , Kawaguchi Shinichi , Kanehisa Nobuko , Miki Kunio , Kasai Nobutami 
Published: July 2006

Abstract
Reactions of bis(trifluoroacetylacetonato)palladium(II), [Pd(tfac)2], with tertiary phosphines followed by pyridine or its derivatives afforded a series of the [Pd(tfac(2–)-C,O)LL′]-type complexes which contain a C,O-chelating trifluoroacetylacetonate dianion and a couple of tertiary phosphine and/or heterocyclic nitrogen base ligands (L and L′). Their structures in solution were studied by 1H, 13C, 19F, and 31P NMR spectroscopy and the molecular structure in a crystal of [Pd(tfac(2–)-C,O)(PPh3)(2,6-Me2-py)]·C6H6 containing triphenylphosphine and 2,6-dimethylpyridine as L and L′ was determined by means of X-ray diffraction.
Preferential Introduction of a Pyridylmethyl Group into Sulfonamides as an Approach to an Intramolecular Transimination
Authors: Iwata Masaaki , Kuzuhara Hiroyoshi 
Published: July 2006

Abstract
N,N′-Bis(p-tolylsulfonyl)-α-ω-alkanediamine disodium salts (n=3, 4, 5, 6, 7, 8, 9, 10) were subjected to monopyridylmethylation by the reaction with 5′-deoxy-5′-chloro- or 5′-deoxy-2′-chloro-3,4′-O-isopropylidenepyridoxine hydrochloride, accompanied by the corresponding bispyridylmethylation. Monopyridylmethylation became remarkable for longer methylene chains of the diamine. Thus, introduction of an amino group protected by a sulfonyl group at the end of either the C2- or the C5-side chains of pyridoxine derivatives was achieved.
The Reaction of 2,4,6-Triphenyl-1,3,5-thiadiazin-1-ium Salt with Active Methylene Compounds
Authors: Shibuya Isao 
Published: July 2006

Abstract
The reaction of 2,4,6-triphenyl-1,3,5-thiadiazin-1-ium tetrafluoroborate with several active methylene compounds was studied. Nitromethane and nitroethane gave 2H-1,3,5-thiadiazines. The compounds possessing a benzoyl group reacted with this salt to give 5-substituted 2,4,6-triphenylpyrimidines, while those possessing a carbamoyl group afforded 5-substituted 4-hydroxy-2,6-diphenylpyrimidines or 4(3H)-pyrimidinone. On the other hand, malononitrile and ethyl cyanoacetate gave 5-substituted 4-mercapto-2,6-diphenylpyrimidines, with the liberation of benzonitrile. It was thus found that 2,4,6-triphenyl-1,3,5-thiadiazin-1-ium tetrafluoroborate reacts with active methylene compounds in fashions similar to that of 2,4,6-triphenyl-1,3-thiazin-1-ium salt.
Oxidizing Action of Hydroperoxides. Oxidation of Alkyl Aryl Ketones by Hydroperoxides
Authors: Maruyama Kazuhiro , Iwamoto Hidetoshi , Soga Osamu , Takuwa Akio 
Published: July 2006

Abstract
The oxidation of alkyl aryl ketones by t-butyl hydroperoxide under basic conditions gave products which resulted from the fission of the carbon-carbon bond between carbonyl carbon and alkyl carbon. The reaction was investigated using chiral alkyl aryl ketones. On the basis of the results, a probable reaction mechanism is proposed.
The Synthesis of Highly Strained Buttaflanes with Aromatic Rings
Authors: Kimura Koji , Ohno Hideki , Morikawa Kiyoshi , Hiramatsu Yasuhiro , Odaira Yoshinobu 
Published: July 2006

Abstract
Dibenzo[4.4.2.2]buttaflanes, syn-13,14:15,16-dibenzopentacyclo[6.4.2.22,7.01,8.02,7]hexadeca-13,15-diene, and syn-13,14:15,16-dibenzohexacyclo[6.4.2.22,7.01,8.02,7.03,12]hexadeca-13,15-diene were synthesized by the intramolecular photocycloaddition of the dibenzo[a,e]cyclooctene derivatives, syn-13,14:15,16-dibenzotricyclo[6.4.2.22,7]hexadeca-1,7,13,15-tetraene and syn-13,14:15,16-dibenzotetracyclo[6.4.2.22,7.03,12]hexadeca-1,7,13,15-tetraene, which had themselves been derived by the catalytic hydrogenation of the biphenylene photodimer, syn-13,14:15,16-dibenzotricyclo[6.4.2.22,7]hexadeca-1,3,5,7,9,11,13,15-octaene, and the pentacyclic compound, syn-13,14:15,16-dibenzopentacyclo[6.4.2.22,7.03,12.04,11]hexadeca-1,5,7,9,13,15-hexaene, respectively.
Applications of Homogeneous Water-gas Shift Reaction. IV. Hydrocarbonylation and Dimerization of Methyl Acrylate with CO and H2O
Authors: Murata Kazuhisa , Matsuda Akio 
Published: July 2006

Abstract
Hydrocarbonylation of methyl acrylate with CO and H2O forms dimethyl 4-oxopimelate in 94% yield based on H2O, the Co2(CO)8-1,2-bis(diphenylphosphino)ethane (diphos) catalyst system being used as in the case of ethylene or propylene. Increasing temperature tends to promote the dimerization and/or hydrodimerization of methyl acrylate to give 1,3-bis(methoxycarbonyl)-1-butene and/or dimethyl 2-methylglutarate. Effects of CO pressure and H2O concentration on the hydrocarbonylation and dimerization were examined at 135 and 165 °C. Catalytically active intermediates for the hydrocarbonylation take part in the dimerization of methyl acrylate.
Photosensitized cis-trans Isomerization of β-Alkylstyrenes
Authors: Arai Tatsuo , Sakuragi Hirochika , Tokumaru Katsumi 
Published: July 2006

Abstract
Triplet sensitized isomerization of a series of β-alkylstyrenes has been investigated with the use of various sensitizers. Among the olefins employed β-t-butyl- and β-t-pentylstyrene were found to give remarkably high ratios of the cis-isomers (&gt;80%) at the photostationary state. This fact is reasonably attributed to lower rate constants for energy transfer from the triplet sensitizers to the cis-isomers than to the trans-isomers.
Bitter Diterpenoids from Rabdosia shikokiana (Makino) Hara
Authors: Ochi Masamitsu , Okamura Mitsuyuki , Kotsuki Hiyoshizo , Miura Iwao , Kubo Isao , Kubota Takashi 
Published: July 2006

Abstract
Three new bitter diterpenoids, shikokianoic acid, shikokianal acetate, and 16,17-epoxyshikokianal acetate, have been isolated from the leaves of Rabdosia shikokiana (Makino) Hara. Their structures were established on the basis of spectral and chemical evidence.