bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanochemical Change in the Solid State and the Solubility of Amobarbital
Authors: Ikekawa Akiko , Hayakawa Sohachiro
Published: July 2006

Influence of ball-milling on the X-ray diffraction pattern, the thermal properties, the IR spectra, the particle size distribution and the solubility of amobarbital was investigated. The fraction of crystal I decreased, and the fraction of crystal III and the amorphous part increased at the first stage of ball-milling. The heat of fusion decreased slightly by ball-milling, which was considered to be due to the increase in the fraction of the amorphous part. The melting point lowered by 1–3 °C and the NH and CO absorptions in the IR spectra were influenced by ball-milling, which was considered to be due to the transformation of crystal I into crystal III. The particle size decreased at the first stage of ball-milling. It was considered that the transformation of crystal I into crystal III was remarkable when the particles were broken. The solubility of amobarbital in the KH2PO4–Na2HPO4 buffer solution with pH of 6.0 increased by ball-milling, which was considered to be due to the increase in the fraction of the amorphous part and crystal III.
Pressure Effect on Rate Constants of Proton-transfer Reactions from 2,4,6-Trinitrotoluene to N,N,N′,N′-Tetramethylguanidine and 1,8-Diazabicyclo[5.4.0]undec-7-ene in Acetonitrile and Dichloromethane
Authors: Sugimoto Naoki , Sasaki Muneo , Osugi Jiro
Published: July 2006

Influence of pressure on the rate constants of the proton-transfer reactions between title compounds was studied in acetonitrile and dichloromethane at 25 °C up to 1000 bar by means of a high-pressure stopped-flow method. In the reaction of 2,4,6-trinitrotoluene (TNT) with N,N,N′,N′-tetramethylguanidine, the volume of activation for the forward reaction ΔVf\eweq is −12.7±1.0 cm3 mol−1 in acetonitrile and −19.0±1.5 cm3 mol−1 in dichloromethane. In the reaction of TNT with 1,8-diazabicyclo[5.4.0]undec-7-ene, ΔVf\eweq is −9.0±1.0 cm3 mol−1 in acetonitrile and −10.8±1.0 cm3 mol−1 in dichloromethane. These results are discussed in comparison with other proton-transfer reactions.
Pressure Dependence and Cationic Radius Effect of the Glass Transition Temperature in Aqueous Alkali Acetate Solutions
Authors: Kanno Hitoshi , Shirotani Ichimin , Minomura Shigeru
Published: July 2006

The glass transition temperature (Tg) is measured as a function of pressure up to 200 MPa for the aqueous Li, Na, K, Rb, and Cs acetate solutions. The effects of cation radius on the glass transition of these solutions are discussed and some attempts are made to correlate Tg (and associated properties) with r (cation radius).
Kinetics for Micelle-Monomer Association-Dissociation Reaction of Surfactants with Hydrophobic Counterions
Authors: Inoue Tohru , Ikeuchi Masaru , Kuroda Takemi , Shimozawa Ryosuke
Published: July 2006

A pressure-jump technique and a spin label technique were applied to the kinetic investigation of the association-dissociation reactions between monomer and micelle in surfactant solutions of STS, TMTS, TETS, and TPTS. The rate constants for the reactions were determined at several temperatures by the pressure-jump experiment. The ESR spectra of a spin probe, 5-SAL, solubilized in the micelles were analyzed in terms of the rotational correlation time, τc. A linear relationship was found between kd, the dissociation rate constant, and τc−1. This indicates that the dissociation rate depends on the fluidity of the micellar interior, and is in accord with the picture drawn by Aniansson et al. for the dissociation process. A qualitative discussion is presented on the activation parameters estimated from the present results according to the scheme presented by Aniansson et al.
The Electronic Structures of Bis(cis-1,2-dicyano-1,2-ethenedithiolato)nickel Complexes
Authors: Sano Mitsuru , Adachi Hirohiko , Yamatera Hideo
Published: July 2006

The core binding energies of N1s and S2s in cis-1,2-dicyano-1,2-ethanedithiolate (maleonitriledithiolate, mnt) complexes were measured by means of X-ray photoelectron spectroscopy (XPS), and the energy differences between N1s and S2s, ΔE, were found to be 171.7–172.6 eV throughout the complexes studied. The lowest ΔE value, 171.7 eV, was shown by [Ni(mnt)2]−. The electronic structures of [Ni(mnt)2]− and [Ni(mnt)2]2− were calculated by the discrete variational Xα method. The XPS measurements and the molecular orbital (MO) calculations provide consistent results that the oxidation state of the nickel atom is +2 for both nickel mnt complexes and that the highest occupied MO is 5b3g, which is mainly localized on ligands and which holds an unpaired electron in [Ni(mnt)2]−.
A Kinetic Study of the Reactions of Several Cobalt(III) Complexes with Ascorbic Acid
Authors: Tsukahara Keiichi , Yamamoto Yasuo
Published: July 2006

The kinetics of the reactions of [Co(phen)3]3+, [Co(bpy)3]3+, and [Co(en)(phen)2]3+ (phen=1,10-phenanthroline, bpy=2,2′-bipyridine, and en=ethylenediamine) with ascorbic acid (H2A) have been studied over the temperature range from 17.0 to 35.0 °C, at an ionic strength of 0.10 mol dm−3 (LiClO4), and over the pH range from 3.60 to 5.04 (acetate buffer). The [Co(phen)3]3+ and [Co(bpy)3]3+ ions were reduced by both HA− (k1 path) and A2− (k2 path) ions: the second-order rate constants at 25.0 °C are (0.40±0.07) dm3 mol−1 s−1 and (5.8±1.1)×106 dm3 mol−1s−1 for the [Co(phen)3]3+ ion, and (0.13±0.02) dm3 mol−1 s−1 and (2.1±0.5) ×106 dm3 mol−1 s−1 for the [Co(bpy)3]3+ ion. The [Co(en)(phen)2]3+ ion was reduced only by the A2− ion; k2=(1.0±0.2) ×106 dm3 mol−1 s−1 (25.0 °C). The [Co(phen)3]3+, [Co(bpy)3]3+, and [Co(en)(phen)2]3+ ions were not reduced by H2A. The activation parameters (ΔH\eweq and ΔS\eweq) for the ascorbate reduction of the [Co(phen)3]3+ ion were larger than those of the [Co(bpy)3]3+ ion. This is in contrast to the results of the self-exchange reactions of the [Co(phen)3]3+⁄2+ and [Co(bpy)3]3+⁄2+ couples. The mechanisms will be discussed in terms of the activation parameters and the Marcus cross relationships.
The Preparation and Characterization of Dichloromanganese(IV) Schiff Base Complexes
Authors: Matsushita Takayuki , Kono Hiroshi , Shono Toshiyuki
Published: July 2006

Some chloromanganese(III) Schiff base complexes react with hydrogen chloride to give deep green complexes with the empirical formula of MnLCl2 or MnL′2Cl2, where H2L denotes quadridentate ligands such as N,N′-disalicylideneethylenediamine and its analogs, and where HL′ denotes bidentate ligands such as N-butylsalicylideneamine and its analogs. These complexes are nonelectrolytes in acetonitrile. Their magnetic moments at room temperature fall within the range of 3.9 to 4.1 BM, and the magnetic susceptibilities obey the Curie-Weiss law with small θ values over the temperature range of 77 to 300 K, indicating that the oxidation state of the manganese ions in these complexes is +IV. The electronic spectra show an intense band around 16000 cm−1 which can be assigned to a charge-transfer transition. In the cyclic voltammograms, two cathodic waves are observed at half-peak potentials around +0.9 V and −0.2 V(vs. SCE); they can be assigned to the reductions of Mn(IV) to Mn(III) and of Mn(III) to Mn(II) respectively. The probable configurations of the complexes are discussed on the basis of the infrared spectra.
The Correlation between the Bonding Properties of Ligands and the Irradiation Effects of Gamma-rays on Iron Compounds
Authors: Maeda Yonezo , Katsuki Yoshihiro , Morinaga Tooru , Takashima Yoshimasa
Published: July 2006

Various iron compounds have been irradiated with gamma-rays of cobalt-60. The foreign-charge states of the irradiated compounds were confirmed by means of Mössbauer spectroscopy. The results showed that high-spin iron(III) compounds with large conjugated molecules and low-spin iron(II) compounds are insensitive to γ-radiations. However, iron(III) compounds with carboxyl groups or reducing ligands and low-spin iron(III) compounds are sensitive to γ-radiations. Further, FeCl2·4H2O was found to be insensitive to radiation up to a total exposure dose of 109 R, in contrast to other ionic iron(II) compounds.
Bis(cyclohexyl isocyanide)palladium(II) Halides and Their Benzene Complexes
Authors: Kajimoto Tsunesuke , Kitano Yukishige , Takahashi Hidetaka , Tsuji Jiro
Published: July 2006

Bis(cyclohexyl isocyanide)palladium(II) chloride, PdCl2(C6H11NC)2 (1) was prepared from PdCl2. The configuration of the complex 1 is cis with respect to the isocyanides. The isocyano group in one cyclohexyl isocyanide takes axial conformation to chair form cyclohexyl group, while another takes equatorial conformation. By recrystallization of 1 from benzene bis(cyclohexyl isocyanide)palladium(II) chloride-benzene, PdCl2(C6H11NC)2(C6H6)2 (2) was prepared. IR spectrum of 2 shows a characteristic absorption at 700 cm−1 which is due to the benzene incorporated in the complex. Similar benzene complex was also prepared from PdBr2.
Preparation, Resolution, and Absorption and Circular Dichroism Spectra of [Co(en)n{NH2CH2CH2P(CH3)2}3−n]3+ and the Related Complexes, and the Absolute Configuration of (+)589-fac-[Co{NH2CH2CH2P(CH3)2}3]3+ Determined by X-Ray Analysis
Authors: Kinoshita Isamu , Kashiwabara Kazuo , Fujita Junnosuke , Matsumoto Keiji , Ooi Shun’ichiro
Published: July 2006

A series of complexes, [Co(en)n{NH2CH2CH2P(CH3)2}3−n]3+ (en=ethylenediamine, n=0,1,2) and three bis(ethylenediamine)cobalt(III) complexes of the related ligands, NH2CH2CH2P(C6H5)2, (S)-NH2CH(CH3)CH2P(C6H5)2, and rac-NH2CH2CH2P(C4H9)(C6H5) were prepared and resolved (or separated) into optical isomers, and their absorption and circular dichroism spectra were recorded. The molecular structure and the absolute configuration of (+)589-fac-[Co{NH2CH2CH2P(CH3)2}3]Br3·3H2O were determined by X-ray analysis. The crystals are lemon-yellow, orthorhombic, a=26.501(8), b=9.573(4), c=10.081(5) Å, space group P212121, z=4. The Co atom is surrounded by 3P and 3N in the facial manner with the average distances of 2.237 and 2.041 Å, respectively. The absolute configuration of the complex ion is Δ. The chelate rings are puckered and chiral to form a pseudo λ gauche conformation.
The Steric Hindrance of the Stepwise Reaction of N-Carboxy α-Amino Acid Anhydride with the α-Amino Acid Ester
Authors: Oya Masanao , Takahashi Tomoko
Published: July 2006

The mechanisms of the reactions of 4-alkyloxazolidinediones (1) (N-carboxy α-amino acid anhydrides(NCAs)) with α-amino acid benzyl ester p-toluenesulfonates (2) were investigated in acetonitrile containing triethylamine at low and room temperatures. Two types of reactions were observed: (1) the polymerization of NCAs was initiated with a small amount of 2 to produce polypeptides (6), and (2) the dipeptide benzyl esters (4) were produced by the stepwise reaction of NCAs with the esters. Both the polymerization and the dipeptide formation (1+2) seemed to be initiated by the nucleophilic attack of the amino group of the ester on the C-5 carbon of NCAs. The polymerization proceeded when the side chains of the amino acid esters (R2) were more bulky than those of the NCAs (R1). On the contrary, dipeptide esters were produced when the side chains of the NCAs (R1) were more bulky than those of the esters (R2).
The Liquid-phase Oxidation of Methylbenzenes by the Cobalt-Copper-Bromide System
Authors: Okada Toshihiko , Kamiya Yoshio
Published: July 2006

The liquid-phase oxidation of methylbenzenes catalyzed by a catalyst system composed of cobalt(II) and copper(II) acetates and sodium bromide was carried out in acetic acid at 150 °C. The corresponding benzyl acetates and benzaldehydes were obtained in high selectivities in most cases. A nuclear-brominated product, i.e., 3-bromo-4-methoxytoluene was also obtained in the oxidation of p-methoxytoluene, which has two different reaction sites, i.e.,  o-positions to the electron-donating methoxyl substituent and the benzyl position. However, the substitution of the bromide ion for the acetate ion in the catalyst system gave satisfactory selectivities for the side-chain oxidation products. In p-xylene oxidation, α,α′-diacetoxy-p-xylene and p-(acetoxymethyl)benzonic acid were also obtained, as well as p-methylbenzyl acetate, though their amounts were small. The oxidation of polymethylbenzenes was also carried out.
The Synthesis of α-d-Galactopyranosyl and α-d-Mannopyranosyl 2-Amino-2-deoxy-α-d-glucopyranosides and the Conformation of Their Glycoside Linkage
Authors: Koto Shinkiti , Inada Shigeru , Zen Shonosuke
Published: July 2006

A new analog of trehalosamine, α-d-galactopyranosyl 2-amino-2-deoxy-α-d-glucopyranoside, was synthesized by the glycosylation of 2,3,4,6-tetra-O-(p-chlorobenzyl)-α-d-galactopyranose with 3,4,6-tri-O-acetyl-2-deoxy-2-(2,4-dinitroanilino)-α-d-glucopyranosyl bromide, using silver perchlorate and tribenzylamine in benzene, followed by chromatographic separation and the subsequent removal of the protecting groups. Similarly, α-d-mannopyranosyl 2-amino-2-deoxy-α-d-glucopyranoside was synthesized. The conformation of the glycoside linkage of these α,α-disaccharides is discussed in relation to the 13C chemical shifts of their anomeric carbons.
Pseudo-sugars. VII. Synthesis of Pseudo-hexopyranose Derivatives with α- and β-Gluco Configurations
Authors: Ogawa Seiichiro , Toyokuni Tatsushi , Kondoh Takashi , Hattori Yoshihisa , Iwasaki Shinichi , Suetsugu Masaru , Suami Tetsuo
Published: July 2006

Several derivatives of pseudo-hexopyranose (5-hydroxymethyl-1,2,3,4-cyclohexanetetrol) with α-gluco, (1,2,4/3,5), and β-gluco, (1,3,5/2,4), configurations were synthesized starting from the compounds obtained by cis-hydroxylation and oxyamination of Dl-di-O-acetyl-(1,3/2)-3-bromomethyl-5-cyclohexene-1,2-diol. The 1H NMR chemical shifts of the acetyl methyl protons of the several acetyl derivatives of N-(p-tolylsulfonyl)-pseudoglucosamines are discussed.
Regio- and Stereoselective Cyclopentannulation with Ketones and Propargyl Alcohol Derivatives. Synthesis of dl-Nootkatone and dl-Muscopyridine
Authors: Hiyama Tamejiro , Shinoda Masaki , Saimoto Hiroyuki , Nozaki Hitosi
Published: July 2006

A highly regio- and stereoselective five-membered ring annulation involving the acid-treatment of propargyl alcohol dianion adducts of ketones is described. The propargyl alcohol adduct of 2-octanone was converted into 2-methyl-3-pentyl-2-cyclopentenone by treatment with sulfuric acid–methanol (1:1) at 0 °C. As the major product, 1-methylbicyclo[5.3.0]dec-6-en-8-one was produced from 2-methylcycloheptanone. Remarkable regioselective cyclopentannulation was observed in 2-methylcyclohexanone and 2,3-dimethylcyclohexanone wherein 1-methyl- and trans-1,2-dimethyl-substituted bicyclo[4.3.0]non-5-en-7-one (BNO) are produced, respectively. With 3-butyn-2-ol, 2-methylcyclohexanone was converted into the cis-1,9-dimethyl-substituted BNO. 4-Isopropyl-2-methylcyclohexanone was transformed into an 83–85:17–15 mixture of c-3-isopropyl-γ-1,c-9-dimethyl-BNO and its 3-epimer. These results are explained in terms of the conrotatory ring-closure of thermodynamically most favorable hydroxypentadienyl cation intermediates. 3-Methoxycarbonyl-cis-1,9-dimethyl-BNO produced from 4-methoxycarbonyl-2-methylcyclohexanone and 3-butyn-2-ol was successfully transformed into dl-nootkatone by converting the methoxycarbonyl group into isopropenyl of correct stereochemistry followed by ring enlargement. Cyclopentannulation using propargyl alcohol dianion adducts of 2-cycloalkenones is discussed. Annulation takes place regioselectively to give conjugated dienones, e.g., (E)-bicyclo[10.3.0]pentadeca-1(12),2-dien-13-one from 2-cyclododecenone. This product is led to dl-muscopyridine by conjugate 1,6-addition of methyl group followed by ring expansion and finally by aromatization with hydroxylamine hydrochloride.
The Structures of Rabdosianin A, B, and C, Three New Diterpenoids from Rabdosia shikokianus Hara
Authors: Ochi Masamitsu , Okamura Mitsuyuki , Kotsuki Hiyoshizo , Miura Iwao , Kubo Isao , Kubota Takashi
Published: July 2006

Three new bitter diterpenoids, rabdosianin A, B, and C, have been isolated from the leaves of Rabdosia shikokianus Hara, and their structures, determined by spectroscopic and chemical methods. Complete assignments of the 1H and 13C NMR data are described.
Fluorination with Xenon Difluoride. 23. Fluorination of Ortho Substituted Aromatic Molecules
Authors: Šket Boris , Zupan Marko
Published: July 2006

The fluorination of 9,10-dihydroanthracene and triptycene with xenon difluoride in the presence of hydrogen fluoride occurred at α and β position with β attack predominating over α attack, while the reaction with acenaphthene resulted in the formation of 2- and 4-fluorosubstituted products, regioselectivity being very little affected by the nature of the catalyst: hydrogen fluoride, boron trifluoride and pentafluorothiophenol. The fluorination of 1,2,3,4-tetrahydro-1,4-methanonaphthalene resulted in the formation of 6-fluoro-1,2,3,4-tetrahydro-1,4-methanonaphthalene, 6,7-difluoro-1,2,3,4-tetrahydro-1,4-methanonaphthalene and rearranged product 1-(2,2-difluoroethyl) indan.
Molecular Deformation Caused by Hydrogen Bonding. 1,3-Dimethylurea
Authors: Fukushima Kunio , Kawai Takeshi
Published: July 2006

Raman spectra of 1,3-dimethylurea were measured for the crystalline state, acetone (proton acceptor) solution and water and methanol (proton donors) solutions. Remarkable differences were observed among the spectra of the aqueous solution and those of the acetone solution and the crystal. The difference is interpreted as due to the molecular deformation caused by hydrogen bonding.
Isomers of the Diamminebis(trimethylenediamine)cobalt(III) Complex
Authors: Sano Mitsuru , Fujita Miho , Sasaki Ken-ichi , Yoshikawa Yuzo , Yamatera Hideo
Published: July 2006

The isomers of [Co(NH3)2(tn)2]3+ were separated by recycling chromatography. The CD spectra of cis isomers were obtained and are compared with the spectra of the corresponding tris complexes. The magnitude of CD intensity of bisdiamine complex is roughly one-third of the corresponding trisdiamine complex.
The Synthesis of Purpurosamine B Derivatives
Authors: Honda Yutaka , Suami Tetsuo
Published: July 2006

Purpurosamine B and its 6-epimer have been found in antibiotic gentamicin C2 and fortimicin A respectively. Methyl 2,6-di-N-acetyl-α-purpurosaminide B and its corresponding 6-epimer have been synthesized from methyl 2-acetamido-2,3,4-trideoxy-α-d-erytho-hexodialdo-1,5-pyranoside.
Facile Dehydrogenative Dimerization of Indolizine Derivatives
Authors: Kakehi Akikazu , Ito Suketaka , Hamaguchi Akihiro , Okano Tsutomu
Published: July 2006

Treatment of 3-unsubstituted indolizines with a dehydrogenating agent such as palladium on carbon in refluxing xylene gave the corresponding 3,3′-biindolizine derivatives in 19–74% yields.
Effects of Crown Ethers on the Critical Micelle Concentration and the Micellar Catalysis of Sodium and Potassium Dodecyl Sulfates in Aqueous Solutions
Authors: Sen\={o} Manabu , Namba Tomiyuki , Kise Hideo
Published: July 2006

The catalytic micellar effects of potassium dodecyl sulfate on the hydrolysis of trimethyl orthobenzoate were found to be much retarded by 15-crown-5 or 18-crown-6.
Chlorination of Acetylenes with Sulfuryl Chloride
Authors: Uemura Sakae , Masaki Ghiaki , Toshimitsu Akio , Sawada Seiji
Published: July 2006

The reactions of some acetylenes with sulfuryl chloride in benzene and carbon tetrachloride at the reflux temperature afford the corresponding (E)- and (Z)-dichloroalkenes in good to moderate yields via homolytic pathway. The kinetically controlled isomer ratios (E⁄Z) depended very much on the kind of acetylenes employed; i.e., 93/7 for 1-octyne to 14/86 for 3,3-dimethyl-1-phenyl-1-butyne in benzene.
Modified Method for the Determination of Stoichiometry and Formation Constant of Molecular Complexes by Differential Refractometry
Authors: Sahai Ram , Singh Vinod
Published: July 2006

A modified method has been proposed for the determination of stoichiometry and formation constant of molecular complexes by Job method using differential refractometry. A more adequate model has been presented and has been verified on some strong, moderate, and weak systems in different solvents at 35 °C. The formation constants obtained by this method are in good agreement with the literature values.
The Reaction of 2-Methylfuran with Methyl Acrylate. Unusual Formation of 1,1′-Bis(5-methyl-2-furyl)ethane and Methyl 3,3′-Bis(5-methyl-2-furyl)propionate
Authors: Maruyama Osamu , Fujiwara Yuzo , Taniguchi Hiroshi
Published: July 2006

The reaction of 2-methylfuran with methyl acrylate in the presence of Pd(OAc)2 gave unusual products such as 1,1′-bis(5-methyl-2-furyl)ethane (22%) and methyl 3,3′-bis(5-methyl-2-furyl)propionate (10%) along with the usual aromatic substitution product. This is a marked contrast to the reaction of furan with olefins.
Determination of the Difference in Hard-sphere Volume of Conformational Isomers from Sound Velocity
Authors: Aoi Masakatsu , Arakawa Kiyoshi
Published: July 2006

The difference in hard-sphere volume of conformational isomers ΔV⁄V was determined from sound velocity data by a method proposed on the basis of the Lebowitz theory of solutions. The ΔV⁄V values between conformers were found to be 6, 9, 12, 7, and 12% for 1,1,2,2-tetrachloroethane, 1,1,2,2-tetrabromoethane, 1-chloropropane, 1-bromopropane, and ethylcyclohexane, respectively.
The DV-Xα MO Study of the Electronic Structures of [M(CN)6]3− (M=Cr, Mn, Fe, and Co) and [Fe(CN)6]4−
Authors: Sano Mitsuru , Adachi Hirohiko , Yamatera Hideo
Published: July 2006

The discrete-variational Xα (DV-Xα) calculations are used for the hexacyano transition-metal complexes, [M(CN)6]3− (M=Cr, Mn, Fe, and Co) and [Fe(CN)6]4−. The calculated values of the core- and valence-orbital energies can be correlated with the XPS results. The Mulliken populations are presented. The calculated d-d excitation energies are in good agreement with the Δ (ligand-field parameter) values obtained from the spectra.
The Decomposition of Hydrogen Iodide and Separation of the Products by the Combination of an Adsorbent with Catalytic Activity and a Temperature-swing Method
Authors: Oosawa Yoshinao
Published: July 2006

The decomposition of hydrogen iodide and the separation of the products by the combination of a column packed with an adsorbent with catalytic activity (platinum-supported active carbon, 2.3 wt%) and a temperature-swing method (450–900 K) are carried out, and the features and the problems of the method are examined. A one-step conversion of hydrogen iodide, 70%, is obtained at 450 K, where the equilibrium conversion is 13%. It is shown that the products of the decomposition of hydrogen iodide containing water are separated from each other.
Thermochromism of Metal Chelates with Triphenylmethane Complexons in Aqueous Solutions. IV. Carbon-13 Nuclear Magnetic Resonance Studies of Xylenol Orange (XO) and Its Zinc(II) Complex
Authors: Nakada Shoji , Ito Tasuku , Yamada Mutsuo , Fujimoto Masatoshi
Published: July 2006

Reversible thermochromism of a Zn(II) complex with 3,3′-bis[bis(carboxymethyl)aminomethyl]-o-cresol-sulfonphthalein (Xylenol Orange, XO) was studied in D2O by means of the 13C NMR method with reference to the data of spectrophotometric and temperature-jump measurements. 13C NMR spectra of XO were measured in the pD range between 2.0 and 11.0 and the signals were assigned. π-Electron conjugations in XO and Zn(II)–XO spread on phenol- and quinonoid-rings through the central carbon atom, but the phenyl ring having an SO3 substituent is not involved in the π-conjugated system. The temperature- and the pD-dependences of 13C NMR spectra of the Zn(II)–XO complex show that the thermochromism is caused by the temperature-dependence of a protolytic equilibrium of a phenolic hydroxyl group of the Zn(II)–XO complex.
Metal Complexes of Peptides. II. Circular Dichroism Spectra and Absolute Configuration of Bis(dipeptidato)cobalt(III) Complexes
Authors: Yasui Takaji , Kawaguchi Hiroshi , Ama Tomoharu
Published: July 2006

Type [Co(dipeptidato)2] complexes (dipeptidato denotes dianions of glycylglycine, β-alanine, -l-alanine, and -l-leucine, β-alanylglycine and -l-alanine, l-alanylglycine and -β-alanine, l-leucylglycine, and l-prolylglycine) and the complex [Co(gly-gly)(l-pro-gly)]− were prepared by a method using lead dioxide as an oxidizing agent, and these complexes were separated into two diastereomers or enantiomers by column chromatography. The absolute configurations of the optical isomers were determined on the basis of their circular dichroism patterns in the ligand transition region.
Metal Complexes Coordinating Pyridine Derivatives. III. Stereoselective Formation of Chromium (III) Complexes of Chiral Quadridentate Ligands
Authors: Yamamoto Yukihiro , Shimura Yoichi
Published: July 2006

Dichloro mononuclear and di-μ-hydroxo dinuclear chromium (III) complexes were prepared with the following three ligands, (S)-N,N′-bis(2-pyridylmethyl)propylenediamine (abbrev. S-picpn), (S,S)-N,N′-bis(2-pyridylmethyl)2,3-butanediamine (abbrev. SS-picbn), and (S,S)-N,N′-bis(2-pyridylmethyl)-1,2-cyclohexanediamine (abbrev. SS-picchxn). The SS-picbn and SS-picchxn ligands produce novel Λ(SS)-cis-α diastereomer of dichloro complex, in which the terminal chelate ring is formed by coordination of equatorially-oriented substituent on the secondary nitrogen atom. An explanation from the viewpoint of steric repulsion is given for the stereoselective formation of Λ(SS) diastereomers for the cis-α dichloro complexes of SS-picchxn and SS-picbn. A similar explanation is also given for stereoselective formation of a limited number of isomers of dinuclear μ-hydroxo complexes of S-picpn, SS-picbn, and SS-picchxn.
Thermal Behavior of a New Type Molybdenum Oxide Obtained by Oxidation of Molybdenum Powder or Molydenum Trioxide with Hydrogen Peroxide
Authors: Kurusu Yasuhiko
Published: July 2006

New molybdenum oxides, Mo-y(yellow) and Mo-b(blue), were obtained by the reaction between molybdenum powder or molybdenum trioxide and hydrogen peroxide. Their reactivity and structure were examined by iodometry, IR, X-ray, and thermal analyses. Mo-y is an acidic oxidant but Mo-b is acidic.
Studies on the Solvent Extraction of Metal Perchlorates III. Extraction Equilibria of Alkaline Earth Ions with Trioctylphosphine Oxide as Perchlorate and Thiocyanate
Authors: Kusakabe Satoshi , Sekine Tatsuya
Published: July 2006

Solvent extraction of alkaline earth metal ions in 1 mol dm−3 sodium perchlorate or thiocyanate aqueous solution with trioctylphosphine oxide (TOPO) in hexane was studied at 25 °C. The extraction in both systems improved in the order: beryllium(II)>calcium(II)>strontium(II)\simeqmagnesium(II)\simeqbarium(II). When the TOPO concentration was the same, the extraction of beryllium or calcium thiocyanate was better than that of the perchlorate, that of magnesium or strontium thiocyanate was nearly similar to that of the perchlorate, while barium perchlorate was extracted better than its thiocyanate. From these results it was concluded that these five perchlorates and strontium and barium thiocyanates were extracted as ion-pairs, [M(topo)4]2+(X−)2, (X−=ClO4− or SCN−), while beryllium thiocyanate was extracted as solvates of noncharged complexes, M(SCN)2(topo)n, (n=2 and 3), and that magnesium and calcium thiocyanates in the organic phase (n=3 and 4) should have both ionic and coordinative properties. The poor extraction of magnesium salts was assumed to be due to their strong hydration.
Determination of Germanium by Atomic Absorption Spectrometry Following Volatile Hydride Generation
Authors: Jin Kazuo , Terada Hiroaki , Taga Mitsuhiko
Published: July 2006

A sensitive technique for determination of germanium was investigated by atomic absorption spectrometry following volatile hydride generation. Of the three types of hydride generator and atomizer systems tested, direct transfer of the generated hydride into nitrogen-hydrogen flame for atomization was found to be suitable. The sensitivity was enhanced more than 40–60% in phosphoric acid medium as compared to hydrochloric acid, malic acid, or tartaric acid media. Interference of nickel(II), gold(III), and cobalt(II) in hydrochloric acid medium was reduced by adding ethylenediaminetetraacetate as a masking reagent or replacing the acid medium by malic acid. Detection limit and relative standard deviation of ten determinations of 0.5 μg germanium(IV) in 20 ml of 0.20 M phosphoric acid were 7 ng (S/N=2) and 4.3%, respectively, with 3 ml of 8 w/v % sodium tetrahydroborate solution. The method was applied to the determination of germanium in standard rocks, concentrations of germanium in JB-1 and JG-1 being evaluated as 1.31 and 1.32 ppm, respectively.
Preparation and Spectroscopic Studies of Cobalt(III) Complexes Containing Optically Active Seven-membered Chelate Ligands
Authors: Kojima Masaaki , Morita Ken’ichi , Fujita Junnosuke
Published: July 2006

New cobalt(III) complexes of the types, trans-[CoCl2L2]+, [Co(NH3)4L]3+, cis-[Co(NH3)2L2]3+, and [Co(en)2L]3+, where L denotes a seven-membered chelate diamine ligand, (R)-2-methyl-1,4-butanediamine or meso- and (R or S)-2,5-hexanediamine, have been prepared. The dichloro complexes decompose gradually even in the solid state, and rapidly in methanol. The ammine and ethylenediamine complexes are stable in acidic water, but decompose gradually in neutral water. The absorption and circular dichroism spectra of all the complexes have been recorded in aqueous or acetone solutions. The circular dichroism spectra in the first absorption band region are changed by the addition of sulfate ions, and the variation has been discussed in terms of the structure of isomers and the conformational instability of the seven-membered chelate rings.
Pyrolytic Sulfurization Gas Chromatography. IX. Determination of the Atomic Ratio between C, H, O, N, Cl, Br, and I in an Organic Halogen Compound
Authors: Hara Tadashi , Fujinaga Kaoru , Okui Fujio
Published: July 2006

The atomic ratio between C, H, O, N, Cl, Br, and I in an organic halogen compound was obtained satisfactorily by gas chromatography and ion chromatography. At first the atomic ratio between C, H, O, and N was determined simultaneously by PSGC and then the atomic ratio between a halogen atom and C, H, O, and N was obtained by estimating the amount of a halogen atom in the reaction residue and by calculating the weight percent in Eq. 4 by use of a correction factor and peak areas in gas and ion chromatograms.
Formation of Anatase Precipitates Containing Fe(III) by the Air Oxidation at 95 °C of Strongly Acidic Solutions
Authors: Kiyama Masao , Takada Toshio
Published: July 2006

Strongly acidic titanium(II)) chloride solutions containing iron (II) sulfate were subjected to oxidation with air at 95 °C. The products consist of spheres, 0.5–1.0 μm in size, each composed of extremely fine particles, 100–150 Å in size. Fe(III) is incorporated up to about 6% of the total metal ions in the product, in spite of the strongly acidic solution. The products, containing H2O and SO42− besides Fe(III), are dehydrated in the temperature range 100–400 °C and the sulfate decomposition begins at about 750 °C in air. The SO42− in the products can be easily removed by washing at room temperature with NaOH solution. No marked differences can be detected in color, magnetic properties, or in growth of the extremely fine particles before and after the dehydration by heat treatment at 500 °C; a change in such physical properties begins to occur at 550 °C. It is concluded that the Fe(III) in the product is interposed between the extremely fine particles, whereas the H2O and SO42− are adsorbed in the spherical poly crystal line particles formed with oxo and hydroxo combination of the extremely fine particles.
The Separation by Means of the Zone-melting Technique and the Spectrofluorometric Determination of Trace Amounts of Anthracene in Phenanthrene
Authors: Furusawa Motohisa , Tachibana Masaki
Published: July 2006

Since ordinarily available phenanthrene contains interfering impurities, such as phenanthrenequinone and fluoranthene, it is difficult to determine anthracene by spectrofluorimetry directly. Trace amounts of anthracene in phenanthrene can, however, be selectively separated from the interfering impurities by means of the zone-melting technique, for the distribution coefficient of anthracene in phenanthrene is greater than unity. The anthracene thus separated is spectrofluorometrically measured using xylene as the solvent. The determination limit of anthracene is 0.05 ppm. In a glass tube with an i.d. of 4 mm, 4.0 g of the sample was charged to a length of about 27 cm, and then the zone-pass was repeated 20 times. The molten zones were set to travel at a speed of 100 mm/h under constant stirring. Exactly 2.5 g of the zone-molten sample was cut out and dissolved in 50 ml of xylene. The fluorescence intensity of the solution was measured at 403 nm with excitation at 378 nm. The recovery of anthracene was 95%, with a coefficient of variation of 0.6%. The incompleteness of the recovery was corrected for.
Optical Resolution of rac-5,5,7,12,12,14-Hexamethyl-1,4,8,11-tetraazacyclotetradecane (L), Circular Dichroism Spectra of Ni(II) Complexes with the Active Ligand, and the Absolute Configuration of (−)589-[{Ni(SS-L)}2(d-tart)(H2O)](ClO4)2·2H2O as Determined by the X-Ray Analysis
Authors: Ito Haruko , Fujita Junnosuke , Toriumi Koshiro , Ito Tasuku
Published: July 2006

The title ligand (L) has been resolved through its d-tartrato-nickel(II) complex. The X-ray analysis shows that the less-soluble (−)589-diastereomer has a dimer structure with the folded macrocycles, [{NiL}2(d-tart)(H2O)](ClO4)2·2H2O, and that the chiral carbon atoms have the absolute configuration of S. Axial methyl groups of geminal dimethyl pairs of each nickel (II) complex in the dimer provide stereoselective environment for the coordination site of the d-tartrate ion. Stereospecific hydrogen-bonds between a secondary amine group of the macrocyclic ligand or coordinated water and hydroxyl or carboxyl oxygens of the d-tartrate ion play also an important role in the optical resolution. Pairs of enantiomers of the free ligand and three isomers of the four-coordinate nickel(II) complex have been isolated. Circular dichroism spectra of various four- and six-coordinate complexes with the optically active ligand have been described.
Synthesis and Structures of Steroidal Oxathiolanes
Authors: Shafiullah  , Ali Hasrat , Ogura Haruo , Takayanagi Hiroaki
Published: July 2006

Synthesis of isomeric oxathiolanes from 6-oxosteroids is described. Configurations at spirocyclic carbon in these compounds have been established on the basis of CD and NMR spectra with the use of shift reagent [Eu(dpm)3].
Intramolecular Interactions between a Group Bearing n-Electrons and a CH2–X Where X is an Electronegative Group
Authors: Izumi Giichi , Yamamoto Gaku , Oki Michinori
Published: July 2006

Conformational equilibrium of 9-(2-acyloxyethyl)-1,4-dimethoxytriptycenes in chloroform-d suggests that the stability of the ±sc conformation increases as the electronegativity of the acyl group increases. The results together with other pertinent data are discussed from the stand point that there is an attractive interaction between the acyloxymethyl and the methoxyl groups in proximity. Reflecting its high ionization potential, the chloro group in 1-position showed no stabilization of the ±sc conformation, although mass spectra and some chemical properties indicate that there is an interaction between the chloro group and highly electronegative CH2X group. A possible correlation of these results with the incipient transition state for SN2 reactions is suggested.
A New Method for Protein Sequence Analysis Using Edman-degradation, Field-desorption Mass Spectrometry and Computer Calculation. Sequence Determination of the N-Terminal BrCN Fragment of Streptomyces erythraeus Lysozyme
Authors: Shimonishi Yasutsugu , Hong Yeong-Man , Katakuse Itsuo , Hara Saburo
Published: July 2006

A new method is described for protein sequence analysis. The principle is realized as follows: 1) determination by field-desorption mass spectrometry of the molecular weights of the constituents in peptide mixtures prepared from a polypeptide or protein by specific cleavage methods, 2) quantitation of the 3-phenyl-2-thiohydantoin derivatives of amino acids liberated successively from the constituent peptides in 1) by Edman-degradation, and 3) determination of amino acid sequences with a computer from the data obtained in 1) and 2). The method was applied to sequence determination of a polypeptide of unknown structure, the N-terminal BrCN fragment of Streptomyces erythraeus lysozyme.
Reaction of Hexafluoropropene Dimers with Organomagnesium and -lithium Reagents
Authors: Ishikawa Nobuo , Butler Sigmund , Maruta Masamichi
Published: July 2006

Nucleophilic reactions of F-2-methyl-2-pentene (1) and (E)-F-4-methyl-2-pentene (2), the dinners of hexafluoropropene, with organomagnesium and -lithium reagents were investigated. The reaction of 1 proceeded readily, giving two alkyl- or aryl-substituted polyfluoroalkenes which resulted from α- and γ-fluorine elimination, respectively. Only phenyllithium reacted with 2, giving also α- and γ-fluorine eliminated phenylpolyfluoroalkenes. The reaction mechanism of γ-elimination was postulated in relation to the electropositive property of the organo group and to Mg–F or Li–F bond formation.
Spectral Behavior of 3,6-Substituted Aminoacridine Dyes with Emphasis on the Perturbation of the Exonuclear Amino Groups
Authors: Yamaoka Kiwamu , Noji Sumihare , Yoshida Mamoru
Published: July 2006

The optical absorption spectra of several derivatives of Proflavine (PF) and Coriphosphine O (CP) were measured in aqueous solutions at 25 °C. The effect of the perturbation of one or both of the exonuclear amino groups on the spectral behavior was studied in order to explore the relationship between the spectra and the chemical structures of the symmetric 3,6-disubstituted acridine dyes which can bind to various polyelectrolytes, often showing metachromasy. The metachromatic spectra of the complexes between 3,6-diaminoacridine dyes and polyanions were reproduced reasonably well when one of the two amino groups of PF was converted to an acylamino group. A similar result was observed when the amino group of CP was acetylated. In these cases, the spectra show two absorption bands of nearly equal intensity on both sides of the single peak of PF and CP in the visible region. These results are indicative of the close similarity in chemical structures between the monacylamino PF and the PF bound to the electron-rich sites of polyanions.
One-step Oxidation of Olefins into α-Phenylseleno Carbonyl Compounds
Authors: Shimizu Makoto , Kuwajima Isao
Published: July 2006

Oxidation of olefins has been examined with the following three types of reagents; (i) (C6H5Se)2–Br2–(Bu3Sn)2O, (ii) (C6H5Se)2–t-BuOOH, and (iii) (C6H6Se)2–(C6H5SeO)2O, and the corresponding α-phenylseleno carbonyl compounds have been obtained directly from the olefins.
The Characterization of a Novel Metathesis Catalyst, β-Titanium Oxide-supported Molybdenum Oxide
Authors: Tanaka Katsumi , Miyahara Koshiro , Tanaka Ken-ichi
Published: July 2006

The results of the X-ray photoelectron spectroscopy of a novel metathesis catalyst, MoOx/β-TiO2, are discussed with reference to its catalytic behavior. It is concluded that the active center for the metathesis reaction of olefin is the molybdenum ion with an oxidation higher than +4 on the average, and that the hydrogen scrambling of olefin during the metathesis is caused by the OH group on the TiO2 surface. During the preparation of this catalyst, the decomposition of titanic acid to TiO2 is found to be accelerated by MoO3; a similar thing can be seen of the reduction of MoO3 to zero-valent molybdenum by TiO2.
Magnetic Interaction in Solvent-free DPPH and DPPH–Solvent Complexes
Authors: Fujito Teruaki
Published: July 2006

Magnetic interaction in solvent-free DPPH and DPPH–solvent complexes has been studied by means of measurements of the magnetic susceptibility, the proton magnetic resonance, and the low-field ESR at very low temperatures. The susceptibility of solvent-free DPPH shows a round maximum at 11 K, and then it decreases with a lowering of the temperature, no ordered state being observed. The DPPH–benzene (1 : 1) complex shows a round maximum of susceptibility at 0.65 K and antiferromagnetic ordering at about 0.40 K. The DPPH–CCl4 (4 : 1) complex shows a curious temperature dependence of the susceptibility, which is interpreted in terms of a two-magnetic sublattice model; one sublattice is in the singlet spin state, while the other is in the paramagnetic state at low temperatures except below 0.45 K. Pair interaction is dominant both solvent-free DPPH and in solvent complexes of DPPH. A theoretical approach to the ordered state of DPPH–benzene is given by taking the inter-pair interaction into account.
Liquid Crystal Formation in Binary Systems. IV. Induction of Smectic Phases in Mixtures of N-(p-Nitrobenzy lidene)-p-aminoazobenzene and Various Electron Donors of the Type N-(p-Substituted Benzylidene)-p-aminoazobenzene
Authors: Fukui Minoru , Matsunaga Yoshio
Published: July 2006

A study of the phase diagrams of binary systems consisting of nematogenic N-(p-nitrobenzylidene)-p-aminoazobenzene and various electron donors of the type N-(p-X-benzylidene)-p-aminoazobenzene revealed the induction of a smectic A phase in the cases where X=MeO, EtO, n-PrO, Me2N, and Et2N and of a smectic B phase as well in the cases where X=EtO and n-PrO. The extent of thermal stability enhancement of the smectic A phase is larger with non-nematogenic dialkylamino derivatives than with nematogenic alkoxy derivatives; this supports our postulate that the smectic phases are stabilized by the intermolecular interaction of the electron donor-acceptor type. The induction of smectic A phases was shown also in all the combinations of the p′-ethoxy derivatives, including the cases where X=H, Me, and Ph.
“Macromolecular Ion Flotation” of MnO4− by Combined Use of Macromolecular Anion and Cationic Surfactant
Authors: Sasaki Tsunetaka , Matsubara Kiyoo , Machida Ikuko
Published: July 2006

MnO4− ions in aqueous solution were subjected to macromolecular ion flotation, a process of flotation applied for an aqueous solution containing organic or inorganic ions to be floated, macromolecular ions including macroscopic or colloidal particles with an ion exchange capacity and polymer ions, and oppositely charged ionic surfactant. The macromolecular anions examined were basic aluminum chloride, polyaluminum chloride, carboxymethylcellulose, sodium polyacrylate, sodium alginate, potassium poly(vinyl sulfate), sodium hexametaphosphate, polyphosphoric acid, polyacrylic acid, bentonite, and sodium metasilicate. As a cationic surfactant, hexadecyltri-methylammonium chloride was used. All the above substances are effective for the MnO4− ion flotation, whereas low molecular substances such as Na3PO4 are ineffective, when used with the cationic surfactant. Molecular models of sublate formed during the macromolecular ion flotation are proposed.
Gas-Solid Chromatographic Studies of Organic Compounds on Zirconium Oxide Beads
Authors: Djordjevic Nebojša M , Milonjic Slobodan K , Kopecni Miroslav M
Published: July 2006

Adsorption properties of synthetic zirconium oxide beads were investigated by the gas-solid chromatography (GSC) method. Retentions of numerous alkanes, alkenes, aromatics and chlorinated compounds were measured in a wide temperature region. It appears that the surface activity of an adsorbent can be easily changed by thermal treatment, and in connection with it, the role of crystallographic structure of the adsorbent is emphasized. Thermodynamic parameters obtained were used for explanation of the adsorbent-adsorbate interaction.
The Design of Organic Metals. Dibenzotetrathiafulvalene-2,3-Dichloro-5,6-dicyano-p-benzoquinone (DBTTF–DDQ)
Authors: Mayerle James J , Torrance Jerry B
Published: July 2006

The electrical and optical properties of the four charge-transfer salts formed between the two donors tetrathiafulvalene (TTF) and dibenzotetrathiafulvalene (DBTTF) and the two acceptors tetracyanoquinodimethan (TCNQ) and 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ are compared. The differences are rationalized on the basis of electrochemical considerations. DBTTF–TCNQ, the compound composed of the weakest donor and acceptor, is found to be a neutral complex. However, TTF–TCNQ, and the new material DBTTF–DDQ are mixed valence and highly conducting. The latter material, which is the first highly conducting salt to contain the common acceptor DDQ, has a room temperature pellet electrical conductivity of 8 Ω−1 cm−1. Finally, the combination of best donor and acceptor, TTF–DDQ, forms an insulating, completely ionic salt. The structure of this salt has been determined and found to crystallize with relatively isolated dimers of TTF and strongly distorted stacks of DDQ.
Spectrophotometric Determination of Copper, Cobalt, Nickel, and Tellurium after Extraction with Morpholine-4-carbodithioate into Molten Naphthalene
Authors: Gautam Mamta , Bansal R K , Puri B K
Published: July 2006

Potassium morpholine-4-carbodithioate has been examined as a reagent for the spectrophotometric determination of copper, cobalt, nickel and tellurium after extraction into molten naphthalene. The extracted mixture of metal complex and naphthalene was dissolved in chloroform and the trace amounts of these metals determined spectrophotometrically. Beer’s law holds in the concentration range Cu: 5.0–70.0, Co: 5.0–81.0, Ni: 6.0–90.0, and Te: 5.7–125.0 μg per 10 ml of the final solution. The molar absorptivity and sensitivity are calculated to be Cu: 1.067×104 mol−1 cm−1, 0.0059 μg/cm2 (440 nm), Co: 1.350×104 mol−1 cm−1, 0.0043 μg/cm2 (360 nm), Ni: 7.920×103 mol−1 cm−1, 0.0088 μg/cm2 (390 nm), and Te: 1.075×104 mol−1 cm−1, 0.0110 μg/cm2 (415 nm). Aliquots containing 25.0 μg of copper, 27.0 μg of cobalt, 24.0 μg of nickel and 25.5 μg of tellurium gave a mean absorbance of 0.420, 0.620, 0.270, and 0.215 with a relative standard deviation of 0.0016, 0.0024, 0.0015, and 0.0013 respectively. The interference of various ions has been studied in detail. Only cobalt interfered in the determination of nickel which was eliminated by extraction first at low pH. Methods were developed for the determination of copper, cobalt and nickel in various alloys. A method was also developed for simultaneous determination of tellurium and selenium in the pure solution, based upon the thermal instability of seleniumelided carbodithioate complex.
The Effects of the BF2- and B(C2H5)2-substitiition for Bridging Hydrogen Atoms in the Cobalt(II), Nickel(II), and Copper(II) Complexes with Some Oximate Ligands
Authors: Nonaka Yasuomi , Hamada Kohsuke
Published: July 2006

Cobalt(II), nickel(II), and copper(II) complexes with dioximes substituted by BF2- and B(C2H5)2-groups for bridging hydrogen atoms were prepared. The BF2-substitution caused a red-shift of d-d band and increase of g⁄⁄-value for copper(II) complexes and positive shift of polarographic half wave potential of nickel(II) complexes. In the case of the B(C2H5)2-substituted complexes, such variations were not observed. The BF2-substituted cobalt(II) complexes are stable under an open atmosphere at room temperature in a solid state and in a DMF solution. These were interpreted in terms of the electron-withdrawing ability of BF2-group in the ligand.
Synthesis of Ethylene Glycol Acetates Catalyzed by Potassium Iodide and Metal Acetate
Authors: Shimizu Kazuo , Imamura Juichi
Published: July 2006

The catalytic activities of various kinds of binary systems consisting of KI and metal acetate were tested in liquid phase oxidation of ethylene in acetic acid at various pressures. KI–Mn(OCOCH3)2 was found to be the most reactive system and a new material, CH3COOCH2CH2OCOCH2OCOCH3, was formed as a major byproduct. It was also found that the main product at an early stage of the reaction was ethylene glycol monoacetate, from which other products were formed consecutively. It is considered that catalytic reaction does not proceed via ICH2CH2I, but via ICH2CH2OH which is formed by the oxidation of ethylene with HIO. On the basis of the rate equation and the results under various reaction conditions, a mechanism of the KI–Mn(OCOCH3)2-catalyzed reaction has been proposed.