bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanical Loading Differentially Regulates Membrane‐Bound and Soluble RANKL Availability in MC3T3‐E1 Cells
Authors: KIM DAE WON , LEE HAHN‐JUN , KARMIN JAIME A. , LEE SE EUN , CHANG SEONG‐SIL , TOLCHIN BEN , LIN SHIPHIN , CHO SAM K. , KWON ANTHONY , AHN JAE MOK , LEE FRANCIS YOUNG‐IN
Published: July 2006

Abstract:  To understand the biochemical response of RANKL in response to mechanical loading, MC3T3‐E1 cells were biequiaxially stretched. A murine RANKL cDNA with double epitopes, pEF6 HA‐RANKL‐V5His, was transfected into MC3T3‐E1 cells, which were then stretched. Endogenous RANKL protein expression increased in response to mechanical loading. Membrane‐bound RANKL (HA‐RANKL‐V5His) increased in cell lysates while soluble RANKL (RANKL‐V5His) decreased in the conditioned media after mechanical loading. This may have resulted from the decreased activity of TACE after mechanical loading. Increased membrane‐bound RANKL may be one of the mechanisms through which osteoblasts adapt to mechanical loading by regulating osteoclastogenic activity in a region‐specific manner.
Stationary-increment Student and variance-gamma processes
Authors: Finlay Richard , Seneta Eugene
Published: July 2006

A continuous-time model with stationary increments for asset price {Pt} is an extension of the symmetric subordinator model of Heyde (1999), and allows for skewness of returns. In the setting of independent variance-gamma-distributed returns the model resembles closely that of Madan, Carr, and Chang (1998). A simple choice of parameters renders {e−rtPt} a familiar martingale. We then specify the activity time process, {Tt}, for which {Tt−t} is asymptotically self-similar and {τt}, with τt=Tt−Tt−1, is gamma distributed. This results in a skew variance-gamma distribution for each log price increment (return)Xtand a model for {Xt} which incorporates long-range dependence in squared returns. Our approach mirrors that for the (symmetric) Student process model of Heyde and Leonenko (2005), to which the present work is intended as a complement and a sequel. One intention is to compare, partly on the basis of fitting to data, versions of the general model wherein the returns have either (symmetric)t-distributions or variance-gamma distributions.
Percolation in the signal to interference ratio graph
Authors: Dousse Olivier , Franceschetti Massimo , Macris Nicolas , Meester Ronald , Thiran Patrick
Published: July 2006

Continuum percolation models in which pairs of points of a two-dimensional Poisson point process are connected if they are within some range of each other have been extensively studied. This paper considers a variation in which a connection between two points depends not only on their Euclidean distance, but also on the positions of all other points of the point process. This model has been recently proposed to model interference in radio communications networks. Our main result shows that, despite the infinite-range dependencies, percolation occurs in the model when the density λ of the Poisson point process is greater than the critical density value λc of the independent model, provided that interference from other nodes can be sufficiently reduced (without vanishing).
Limiting dependence structures for tail events, with applications to credit derivatives
Authors: Charpentier Arthur , Juri Alessandro
Published: July 2006

Dependence structures for bivariate extremal events are analyzed using particular types of copula. Weak convergence results for copulas along the lines of the Pickands-Balkema-de Haan theorem provide limiting dependence structures for bivariate tail events. A characterization of these limiting copulas is also provided by means of invariance properties. The results obtained are applied to the credit risk area, where, for intensity-based default models, stress scenario dependence structures for widely traded products such as credit default swap baskets or first-to-default contract types are proposed.
Regulation of Arabidopsis tapetum development and function by DYSFUNCTIONAL TAPETUM1 (DYT1) encoding a putative bHLH transcription factor
Authors: Zhang Wei , Sun Yujin , Timofejeva Ljudmilla , Chen Changbin , Grossniklaus Ueli , Ma Hong
Published: July 2006

In flowering plants, male fertility depends on proper cell differentiation in the anther. However, relatively little is known about the genes that regulate anther cell differentiation and function. Here, we report the analysis of a new Arabidopsis male sterile mutant, dysfunctional tapetum1 (dyt1). The dyt1 mutant exhibits abnormal anther morphology beginning at anther stage 4, with tapetal cells that have excess and/or enlarged vacuoles and lack the densely stained cytoplasm typical of normal tapetal cells. The mutant meiocytes are able to complete meiosis I,but they do not have a thick callose wall; they often fail to complete meiotic cytokinesis and eventually collapse. DYT1 encodes a putative bHLH transcription factor and is strongly expressed in the tapetum from late anther stage 5 to early stage 6, and at a lower level in meiocytes. In addition, the level of DYT1 mRNA is reduced in the sporocyteless/nozzle(spl/nzz) and excess microsporocytes1/extra sporogenous cell(ems1/exs) mutants; together with the mutant phenotypes, this suggests that DYT1 acts downstream of SPL/NZZ and EMS1/EXS. RT-PCR results showed that the expression levels of many tapetum-preferential genes are reduced significantly in the dyt1mutant, indicating that DYT1 is important for the expression of tapetum genes. Our results support the hypothesis that DYT1 is a crucial component of a genetic network that controls anther development and function.
Preparation, Characterization, and Some Properties of a T-Cage-Type S-Bridged RhIII4ZnII3 Heptanuclear Complex with a Defective [Zn3HO]5+ Core. Crystal Structure of Spontaneously Resolved [{Rh(aet)3}4Zn3HO]Br5 (aet = 2-Aminoethanethiolate)
Authors: Konno Takumi , Okamoto Ken-ichi , Hidaka Jinsai
Published: July 2006

The reaction of fac(S)-[Rh(aet)3] with ZnBr2 in water produced a T-cage-type S-bridged polynuclear complex with a “defective” [Zn3HO]5+ core, [{Rh(aet)3}4Zn3HO]Br5 (1Br5), which was subject to spontaneous resolution to give and isomers. 1 was also optically resolved into the two isomers with use of [Sb2(R,R-tartrate)2]2−. The crystal structure and absolute configuration for the spontaneously resolved isomer were determined by X-ray crystallography. [{Rh(C2H6NS)3}4Zn3HO]Br5·9H2O, crystallizes in the cubic space group P213 with a = 19.186 (1) Å, V = 7062.1 (4) Å3, Z = 4, and R = 0.0648. In 1 the four octahedral fac(S)-[Rh(aet)3] subunits are bound to a quasi-tetrahedral [Zn3HO]5+ core in a tetrahedral arrangement. The chiral configurations are regulated to Δ for all fac(S)-[Rh(aet)3] subunits and R for all asymmetric bridging sulfur atoms in -1, giving a quasi-T symmetrical structure. 1 is unstable in water and convertible to a T-cage-type octanuclear complex with a “complete” [Zn4O]6+ core, [{Rh(aet)3}4Zn4O]6+ (2), and to a linear-type S-bridged trinuclear complex, [Co{Rh(aet)3}2]3+, by adding ZnBr2 and [CoCl(NH3)5]Cl2, respectively. The electronic absorption and circular dichroism (CD) spectral behavior of 1 are discussed in comparison with those of 2.
Structures and Properties of Ternary Copper(II) Complexes Involving a Halogen Substituted Phenylalanine and 2,2′-Bipyridine. Intermolecular Interactions between Halo and Organic Groups
Authors: Sugimori Tamotsu , Masuda Hideki , Yamauchi Osamu
Published: July 2006

Structural and spectroscopic studies have been performed on the ternary Cu(II) complexes containing 4-halophenylalanines (XPhe) (X = I or Br) and 2,2′-bipyridine (bpy). The absorption spectra of the 1 : 1 : 1 Cu(bpy)(XPhe) systems exhibited a single d–d peak at 605—608 nm (pH 6—7), and the band centered at ca. 320 nm due to the charge transfer interaction between the substituted phenyl ring and bpy was observed in the difference spectra in the near ultraviolet region. Three complexes with XPhe, [Cu(bpy)(Dl-IPhe)(NO3)] (1), [Cu(bpy)(Dl-BrPhe)(NO3)] (2), and [Cu(bpy)(l-IPhe)]ClO4 (3) were isolated as crystals, and the structures were determined by the X-ray diffraction method. Complex 1 crystallizes in the monoclinic space group, P21/n, with four molecules in a unit cell of dimensions a = 5.292(1), b = 27.315(8), c = 13.848(2) Å, β = 90.05(2)°. Complex 2 also crystallizes in the monoclinic space group, P21/n, with four molecules in a unit cell of dimensions a = 5.293(5), b = 27.18(1), c = 13.540(6) Å, β = 90.03(6)°. The Cu(II) ion in each complex is in a five-coordinate distorted square-pyramidal geometry. Complex 3 crystallizes in triclinic space group P1 with two independent molecules in the asymmetric unit in a unit cell of dimensions a = 18.329(4), b = 10.701(1), c = 5.9287(9) Å, α = 73.91(1), β = 90.02(2), γ = 105.93(2)°. The Cu(II) ion is in a four-coordinate, slightly distorted square-planar geometry. The phenyl ring of XPhe in 1 and 2 is located perpendicular to the bpy plane, and no intramolecular stacking was observed. The phenyl ring of L-IPhe in 3 is tilted over the coordination plane to be stacked with bpy with the average spacing of 3.23 and 3.24 Å. The crystal structures revealed close contacts between the halogen atoms and the carbon atoms of the bpy ring in complexes 1 and 2, with the distances of I···C = 3.54 Å and Br···C = 3.47 Å for 1 and 2, respectively. A close contact between the iodine and carbonyl oxygen was also detected in the crystal structure of 3 with the I···O distance of 3.1 Å. Possible significance of these interactions has been discussed in relation to thyroid hormone-receptor bonding.
Direct Electrochemistry of Nitrite Reductase from Achromobacter cycloclastes IAM 1013
Authors: Kohzuma Takamitsu , Shidara Sohsuke , Suzuki Shinnichiro
Published: July 2006

The cyclic voltammetry of the nitrite reductase from Achromobacter cycloclastes IAM 1013 exhibited well defined voltammetric response at a di-4-pyridyl disulfide (4-pyds) modified gold electrode in the presence of A. cycloclastes apopseudoazurin. The midpoint potential, E1/2, of the native and type II copper-depleted (T2D) nitrite reductase obtained from the voltammogram were estimated to be 240 mV and 204 mV vs. NHE, respectively. The almost identical current value of the native and T2D reductase suggested that the voltammetric behavior contributed from the type 1 copper site. When nitrite was added into the nitrite reductase solution (pH 7.0), an enhanced sigmoidal cathodic current-potential curve indicating the catalytic regeneration of oxidized nitrite reductase was observed. The rate constant of nitrite reduction and the Michaelis constant, Km, of the native reductase were estimated to be 5 × 102 mol−1 dm3 s−1 and 7 × 10−4 mol dm−3, respectively. The rate constant of the nitrite reduction and the Km value of T2D nitrite reductase were also estimated to be 1 × 102 mol−1 dm3 s−1 and 3 × 10−3 mol dm−3, respectively. These results suggested that the nitrite reduction activity is closely related with type II copper site.
Spin Trapping as Applied to Radicals Produced by Chemical Reaction. III. Intermediates of the Reactions of Dibenzoyl Peroxide with Diethylamine and Diphenylamine
Authors: Nishimura Norio , Nakamura Tatsuya , Sueishi Yoshimi , Yamamoto Shunzo
Published: July 2006

The reactions of dibenzoyl peroxide (BPO) with diethylamine (DEA) and diphenylamine (DPA) have been studied by means of an ESR technique combined with spin-trapping. In the case of the DEA/BPO system, diethylnitroxide was formed, while for the DPA/BPO system diphenylaminyl was detected. Three kinds of traps (N-t-benzylidene-t-butylamine N-oxide, 2-methyl-2-nitrosopropane, and 2,4,6-tri-t-butylnitrosobenzene) were used. Different kinds of spin-adducts were formed depending on such conditions as the steric circumstances, radical stabilities and solvent effects. The differences in the reaction mechanisms for these systems are discussed.
Electrophilic Substitution of Monosubstituted Pyrenes
Authors: Minabe Masahiro , Takeshige Shouji , Soeda Yuuji , Kimura Takao , Tsubota Motohiro
Published: July 2006

Bromination and the Friedel–Crafts acetylation of monosubstituted pyrenes were examined. Acetylation of 1-acetyl- and 1-ethylpyrene occurred at the 8-, 6-, or 3-position, but the reaction of 1-methoxypyrene afforded only the 8- and 6-acetyl derivatives. By acetylation, 4-acetylpyrene yielded the 1- and 6-acetyl compounds, and 4-ethylpyrene gave the 6- and 8- derivatives. Also, 4-bromopyrene afforded the corresponding 8-, 6-, and 1-acetyl derivatives by the same reaction. Bromination of 1-ethyl- and 4-ethylpyrene yielded the 8- and 6-bromides, but the reaction of 1-nitro- and 1-bromopyrene took place at the 6-, 8-, or 3-position. The formation ratio of these regioisomers differs by the substituents. The regioselectivity on the acetylation accords in some degree with the prediction based on the 13C NMR chemical shift of each position. The relative rates of these electrophilic substitutions correlate to the substituent constant, σ+, of the substituent attached to the pyrene.
Crystal Structure and Conformational Analysis of 3β,17β-Diacetoxy-8,9-seco-5α-androstane-8,9,11-trione
Authors: Okada Kenji , Koyama Hirozo
Published: July 2006

The crystal and molecular structures of the title compound 1 have been determined by direct methods. The crystals are monoclinic, space group P21, with a = 12.512(2), b = 7.436(2), c = 12.252(2) Å, β = 102.62(1)°, Z = 2. The structure was refined by full-matrix least-squares calculations to a final R of 0.056 for 2268 independently observed reflections. This tricylic compound consists of five-, six-, and ten-membered rings and is slightly bent, including two OAc side chains. The six-membered ring A has a typical chair conformation and the ten-membered ring B adopts a chair-chair conformation. Ring C is a normal β envelope. The ring junctions of both A/B and B/C are trans fusion. Two double bonds [C(8)=O(2), C(11)=O(4)] and two methyl groups [C(18), C(19)] of ring B are oriented α face, and one double bond [C(9)=O(3)] is on the β face of this ring. The O–C–O bond distances in the OAc side chains show partial double-bond characters.
An Effective Method for Acylation of Weakly Nucleophilic Anilines with Silyl Carboxylates via Mixed Anhydrides
Authors: Miyashita Mitsutomo , Shiina Isamu , Mukaiyama Teruaki
Published: July 2006

In the presence of a catalytic amount of active titanium(IV) salt generated in situ from 1 mol of TiCl4 and 2 mol of AgOTf, weakly nucleophilic anilines react under mild conditions with nearly equimolar amounts of silyl carboxylates to afford the corresponding anilides in excellent yields using 4-(trifluoromethyl)benzoic anhydride. The mixed anhydride formed in situ from trimethylsily acetate and 4-(trifluoxomethyl)benzoic anhydride, a key intermediate of this reaction, was detected by 1H NMR experiment. Further, it was shown that the reaction of the mixed anhydrides and 2-nitroaniline was faster than that of the corresponding homo anhydrides and 2-nitroaniline.
Selective Oxidation of the α-Methylene of the Bridge in Ferrocenophanes with Silver Oxide or Silver Perchlorate/Sodium Methoxide
Authors: Hisatome Masao , Watanabe Jun , Yamakawa Koji
Published: July 2006

The treatment of ferrocenophanes with AgO, Ag2O or AgClO4/CH3ONa in methanol gave oxidized products at the α-methylene of the bridge. In the reaction of [m][n]ferrocenophanes (m, n = 3, 4, 5; m > n), the α-methylene of the longest bridge [m] was oxidized in preference to that of the shorter bridge [n]. A reaction mechanism via a radical and/or cation species on the α-methylene of the bridge is proposed.
Synthetic Photochemistry. LXII. The Photoaddition of 4-Methyl-2-oxo-γ-valerolactone to Cycloalkenes
Authors: Hatsui Toshihide , Kitashima Toshio , Takeshita Hitoshi
Published: July 2006

Photocycloaddition of 4-methyl-2-oxo-γ-valerolactone to cycloalkenes gave [2+2] cycloadducts, together with the ene reaction products. The stereostructures of photoproducts were identified by detailed NMR spectral analyses including NOE experiments. The photocycloadducts were convertible to (2-alkenylcycloalkyl)glyoxalic acids.
Mechanistic Studies on trans-Dicarbonyl Phosphine Complexes of Molybdenum(I)
Authors: Abdel-Hamid Refat , El-Samahy Ahmed A , Rabia Mostafa K M , Taylor Norman , Shaw Bernard L
Published: July 2006

The electrode mechanism of trans-dicarbonyl phosphine complexes of molybdenum(I), trans-[Mo(CO)2(P-P)2]PF6 [where P-P = ph2PCH2CH2Pph2(dppe), or ph2PCH=CHPph2 (dppen)] was investigated by cyclic voltammetry and convolution and deconvolution potential sweep voltammetry in 0.1 mol dm−3 TBAP/CH2Cl2 solution at a platinum electrode. The complexes are both oxidized and reduced in one-electron processes. The oxidation and reduction processes are follows a well-defined ECirrev mechanism. Digital simulation and comparison with the experimental cyclic voltammetric results was used for determination of homogeneous and heterogeneous rate constants values.
An X-Ray RDF Study on the Glass 50AgI–25Ag2O–25MoO3
Authors: Patnaik S , Seshasayee M , Aravamudan G , Ohtaki Hitoshi
Published: July 2006

A structural investigation using an X-ray RDF (radial distribution function) technique was carried out for a glass of composition 50AgI–25Ag2O–25MoO3 (in mole% units). Results indicated the presence of strong Ag–I interactions at rAg–I = 287 pm and the average number of iodine atoms around an Ag atom, nAg–I was 0.77. Two Ag–O interactions characterized by rAg–O = 197 pm, nAg–O = 1.8 and rAg–O = 234 pm, nAg–O = 2.6 were also observed. The structural parameters of the glass former MoO3 were given as rMo–O = 198 pm and nMo–O = 5.5. The results showed that AgI was dispersed in the glassy matrix.
Kinetic and Equilibrium Investigation of the Proton Uptake Process in the Complex Formation between Counter-Charged Ionic Polypeptides
Authors: Sano Takayuki , Nakatsuka Thoru , Inoue Katsuaki
Published: July 2006

To clarify the mechanism of polymer complex formation between counter-charged polymers, kinetic and equilibrium experiments concerning the complexation of poly(l-α-glutamic acid) (PGA) with poly (l-α-lysine) (PLL) were performed at around pH 5.5 by the stopped-flow method. The reaction kinetics observed with electric conductivity detection and direct proton detection using the hydrogen ion-sensitive field-effect transistor suggests that the complex formation between these polymers proceeds through two processes of a fast proton release within 10 ms and a slow proton uptake within a few seconds. Further experiments using the various chain lengths of PGA and a variety of combinations of polymers and their counter-charged small ion, (e.g., PGA and amines or metal ions, PLL and carboxylic acids) have revealed that slow proton uptake in their complex formation is specific for a system which includes both a polymer and its counter-charged ions of divalent or more, and that this proton uptake is due to rearrangement of the polymer after fast electrostatic binding as a cooperative process.
Vertical Ionization Potentials of Alkoxides in Solution
Authors: Sakai Kanna , Watanabe Iwao , Yokoyama Yu
Published: July 2006

The photoelectron-emission threshold energies were determined for aqueous and alcoholic solutions of potassium hydroxide and potassium metal. The energies correspond to the vertical ionization potentials of the solutes. The results are in accord with the fact that in alcohol-rich solutions the hydroxide ion reacts with alcohol to produce the alkoxide ion. The threshold energy for the alkoxide ion reflects the ionization potential of the alkoxide ion in a vacuum and the solvation effect. The difference in the ionization potential in a vacuum and in a solution, which is due to the solvation effect, was found to correlate with the acceptor number of the solvent.
Transmembrane Rectified Electron Transfer through π-Conjugated Electroactive Langmuir–Blodgett Monolayers on Gold Electrodes
Authors: Kunitake Masashi , Nasu Kenji , Manabe Osamu , Nakashima Naotoshi
Published: July 2006

Novel amphiphiles with π-conjugated electroactive groups, 1-methyl-4-[2-[4-[2-(4-pyridyl)vinyl]phenyl]vinyl]pyridinium perchlorate (1), and 1-methyl-4-[2-[4-[2-(4-quinolyl)vinyl]phenyl]vinyl]quinolinium perchlorate (2), were designed and synthesized. Both compounds formed expanded monolayers at air–water interfaces. The monolayers transferred on gold disk electrodes at 25 mN m−1 by the Langmuir–Blodgett technique (horizontal lifting method) show one electron reduction/oxidation couple: Epa = −0.86 V, Epc = −1.08 V vs. SCE for 1/Au and Epa = −0.78 V, and Epc = −0.84 V vs. SCE for 2/Au. Rectified transmembrane electron transfer through the LB monolayers of 1 and 2 on gold electrodes to [Fe(CN)6]3− in aqueous solutions has been proved by cyclic voltammetry and potential-step chronocoulometry.
Syntheses and Characterization of Bromo- and Chloro(phthalocyaninato)bismuth(III) Complexes
Authors: Isago Hiroaki , Kagaya Yutaka
Published: July 2006

By the reactions of BiX3 (X = Cl−, Br−, I−, and NO3−) with Li2(pc) (pc = phthalocyaninate dianion, C32H16N82−) in dimethyl sulfoxide, N,N-dimethylformamide, acetonitrile, and acetone, [Bi(pc)X] complexes have been produced. These complexes were also produced by heating a mixture of BiX3 and phthalonitrile. Among them, [Bi(pc)Cl] and [Bi(pc)Br] were isolated for the first time as a phthalocyanine complex of group-15 elements and successfully characterized by elemental analyses, solution chemistry, electronic and IR spectroscopy. The latter two complexes were soluble in polar solvents, but were insoluble in nonpolar solvents. In solutions, bismuth(III) in [Bi(pc)X] was labile and was readily expelled from a pc ring by a trace amount of water, acids, and bases, and it was replaced by a divalent transition metal upon the addition of MSO4 (M = cobalt(II), nickel(II), copper(II), and zinc(II)) forming [M(pc)]. The electronic and IR spectra of the [Bi(pc)X]s were characteristic of the usual metallophthalocyanines, except that a hyper metal-to-ligand charge-transfer band appeared in their electronic spectra.
Intercalation of Ferrocene and Its Derivatives into VxNb1−xOPO4 (x = 0, 0.06, 0.11, and 0.21) Interlayer Spaces
Authors: Okuno Shoji , Matsubayashi Gen-etsu
Published: July 2006

Ferrocene, FcH [Fc = (C5H5)Fe(C5H4)], (ferrocenylalkyl)trimethylammonium iodides, [Fc(CH2)nNMe3]+I− (n = 1 or 2), and 1,2-diferrocenylethane, FcCH2CH2Fc, have been intercalated into the V0.21Nb0.79OPO4 interlayer space. The V(V) ion is reduced by the iodide ion and/or the Fc centers, the Nb(V) ion being not reduced. The long-axis direction of the guest molecules is arranged approximately parallel to the swelling V0.21Nb0.79OPO4 sheet. Some Fc centers of FcCH2CH2Fc and FcCH2CH2NMe3+ are not oxidized in spite of their proximity to the metal ion site of the V0.21Nb0.79OPO4 lattice because most of the V sites are isolated from other V sites owing to the low V contents. Ferrocenylalkylamines, FcCH2NMe2 and FcCH2CH2NH2, have been intercalated into the VxNb1−xOPO4 (x = 0, 0.06, 0.11, and 0.21) interlayer spaces, accompanied with the protonated amino groups and the Nb(V) and reduced V(IV) sites. ESR signals of the V0.06Nb0.94OPO4 intercalation compounds exhibit hyperfine structures due to the V(IV) nucleus (I = 7/2). With the increase of the V content in the host lattice, ESR signals are further broadened owing to the dipole–dipole and/or exchange interactions among the V(IV) sites.
Preparation and Characterization of Dinuclear Cobalt(III) Complexes Containing Four Different Kinds of Ligands; Glycinato, Ethylenediamine, Ethylenediamine-N,N′-diacetato, and μ-Hydroxo
Authors: Ama Tomoharu , Yonemura Toshiaki , Kawaguchi Hiroshi , Yasui Takaji
Published: July 2006

Four geometrical isomers of [Co(gly)(en)Co(edda)(μ-OH)2]+ were prepared by treating a solution containing [Co(edda)(OH2)2]+ and [Co(gly)(en)(OH2)2] 2+ under basic condition and optically resolved by the chromatographic method. The geometrical structures and absolute configurations of the optically active isomers were assigned on the basis of the NMR, UV, and CD spectral data; the assignments were confirmed based on the spectral data of the mononuclear species which were obtained by the acid hydrolysis of each isomer. Two of the four geometrical isomers are constructed with the α-[Co(edda)(μ-OH)2] and mer(O)-[Co(gly)(en)(μ-OH)2] moieties, and the other two with the β-[Co(edda)(μ-OH)2] and fac(O)-[Co(gly)(en)(μ-OH)2] moieties, the dinuclear structures being stabilized by the two N–H···O hydrogen bonds between the amino H on one metal ion and the carboxyl O on the other metal ion in the dinuclear complex ion.
Preparation and Some Properties of Tetraamine Cobalt(III) Complexes with Monodentate Thiolate or Sulfinate Ligands
Authors: Konno Takumi , Umehara Hideki , Okanoto Ken-ichi , Hidaka Jinsai
Published: July 2006

Tetraamine cobalt(III) complexes with monodentate thiolate ligands, [Co(RS)2(amine)4]+, were newly prepared, where R is CH3 or C2H5 and (amine)4 is bis(ethylenediamine) ((en)2), triethylenetetramine (trien), or tris(2-aminoethylamine) (tren). The (en)2 and trien thiolato complexes selectively formed the cis and cis–α isomers, respectively. The oxidation reactions of [Co(RS)2{(en)2 or (trien)}]+ with use of excess H2O2 gave the corresponding S-bonded sulfinato complexes [Co(RSO2-S)2{(en)2 or (trien)}]+ with retention of the initial geometries, while [Co(CH3SO2-S)2(tren)]+ was not formed by the same oxidation reaction of [Co(CH3S)2(tren)]+. The cis-(en)2 and cis–α-trien complexes were optically resolved by the fractional crystallization or column chromatography. The obtained isomers were characterized on the basis of the absorption, CD, and 13C NMR spectra. The thiolato complexes exhibited absorption spectral changes with time in aqueous solutions, which are ascribed to the replacement of the thiolate ligands by H2O.
Cage Enlargement of 1,4-Bis(hydroxymethyl)pentacyclo[4.2.0.02,5.03,8.04,7]octane to a Tetracyclo[4.3.0.03,9.04,7]nonane System in Formic Acid
Authors: Hasegawa Takeshi , Kimura Yoshihide , Kuwatani Yoshiyuki , Higuchi Hiroyuki , Hatanaka Minoru , Ueda Ikuo
Published: July 2006

Cationic rearrangement of 1,4-bis(diarylhydroxymethyl)pentacyclo[4.2.0.02,5.03,8.04,7]octanes (1) in formic acid gave new cage compounds, 8,8-diaryl-2-diarylmethylene-exo-5-(formyloxy)tetracyclo[4.3.0.03,9.04,7]nonan-7-ols (3) and new cage-degradation products, 5,5-diaryl-4-[4-(diarylmethylene)-2-cyclobutenyl]-2-cyclopenten-1-ones (4) along with Wagner–Meerwein rearrangement products, pentacyclo[5.3.0.02,5.03,9.04,8]decanes (5; C2-bishomocubanes) and pentacyclo[5.3.0.02,6.03,9.04,8]decanes (6; D2h-bishomocubanes). 9,9-Diaryl-4-(diarylhydroxymethyl)pentacyclo[4.3.0.02,5.03,8.04,7]nonan-1-ols (2) gave 4, 5, and 6 without the formation of 3. A Wagner–Meerwein 1,2-bond shift of 1 gave key intermediates 2 which were converted into 3 via homoallylic rearrangement, into 4 via pinacol–pinacolone-like rearrangement, or into 5 and 6 via Wagner–Meerwein rearrangement.
Solvent Effects on Extraction of Sodium Picrate with 15-Crown-5. The Determination of Ion-Pair Formation Constant of Crown Ether–Metal Salt 1 : 1 : 1 Complex in Water
Authors: Takeda Yasuyuki , Takagi Chihiro
Published: July 2006

In order to determine the ion-pair formation constant of a crown ether–metal salt complex (1 : 1 : 1) in water, an equation is derived from the regular solution theory. Then, the theoretical predictions are verified experimentally by solvent extraction with 15-crown-5 (15C5), sodium picrate (NaA), and various organic solvents of low dielectric constant. The partition constants of 15C5 and the actual overall extraction constants of NaA with 15C5 were determined at 25 ± 0.2 °C. The partition constants of the Na(15C5)A complex are calculated from these data, the literature value for the complex-formation constant of Na(15C5)+ in water, and the ion-pair formation constant (KNa(15C5)A) in water determined in this study (log KNa(15C5)A = 4.09 ± 0.23 at 25 °C). The distribution behavior of 15C5 and Na(15C5)A is explained by the regular solution theory. The obtained molar volumes V/cm3 mol−1 and solubility parameters δ/cal1/2 cm−3/2 are as follows; V15C5 = 189 ± 34, VNa(15C5)A = 215 ± 46, δ15C5 = 12.0 ± 0.1, and δNa(15C5)A = 12.0 ± 0.1.
Thermal Behavior of Polyaniline Due to Anodic Oxidation in Various Aqueous Solutions
Authors: Maeda Yasuhisa , Katsuta Ai
Published: July 2006

The anodic oxidation of polyaniline in aqueous solutions containing SO42− and PO43− ions caused an exothermic change at lower potential and an endothermic change at higher potential, but only the exothermic change was observed in the anodic process of polyaniline in a solution containing ClO4− ions.
Preparation of 4-Bromo- and 4-Chloro-3-t-butylphenol
Authors: Fukata Gouki , Kubota Yukihiro , Mataka Shuntaro , Thiemann Thies , Tashiro Masashi
Published: July 2006

4-Bromo- and 4-Chloro-3-t-butylphenol, two potent fungistatics, were prepared in an efficient 3-step synthesis from commercially available materials. Crucial to the synthesis is the use of halo-substituents as positional protective groups.
Effect of Some Tetrabutylammonium Salts on the Impedance Behavior of Indium in Acidic Media
Authors: El-Sayed Adbel -Rahman , Mohran Hossnia , Rashwan Farouk
Published: July 2006

The ac impedance of a planar indium electrode in both HCl and H2SO4 solution was measured at −20, 0.0, and 10 mV vs. the open circuit potentials. Various amounts of Bu4NBF4, Bu4NPF6, and Bu4NClO4 were gradually introduced to the electrolytic solution and the impedance of the electrode was remeasured. Subsequently, Rs, Rp, and Cdl, in the absence and presence of the additives, were computed and compared. It was found that Bu4NBF4 has an inhibitive action in both acids. On the other hand, acceleration of the electrochemical processes in the presence of Bu4NPF6 also in both acids, is observed. However, some retardation of the electrode reactions was obtained at the lowest concentration of the additive only in HCl. It is noteworthy that Bu4NClO4 has contradictory effects on the electrochemical processes, i. e. an inhibitive action in HCl solution, whereas in H2SO4 the electrode reactions are significantly enhanced.
Solvent Dependence of Magnetic Field Effects upon Photoisomerization of 2-(3,3-Dimethyl-1-butenyl)naphthalene in the Presence of Electron Acceptors
Authors: Sakuragi Hirochika , Nakagaki Ryoichi , Naitoh Kazuhiko , Oguchi Takahisa , Arai Tatsuo , Tokumaru Katsumi , Nagakura Saburo
Published: July 2006

The efficiency of isomerization of trans-2-(3,3-dimethyl-1-butenyl)naphthalene (t-BN) in the presence of electron acceptors was reduced by an applied magnetic field in polar solvents such as acetonitrile. This effect together with laser flash photolysis studies indicates that the precursor of isomerization is the BN triplet arising from intersystem crossing of a singlet radical pair consisting of a t-BN cation and an acceptor anion. The external magnetic field effect as well as laser flash photolysis was employed to estimate the contribution of ion radical pairs to the isomerization of t-BN in the presence of p-dicyanobenzene in various solvents. The t-BN triplet was produced most efficiently almost through an exciplex in chloroform (ε = 4.8) among the employed solvents.
A Convenient Synthetic Method for Pure Oxo(phthalocyaninato)titanium(IV) and Application to Other Metal Phthalocyanines
Authors: Yao Jiachang , Yonehara Hisatomo , Pac Chyongjin
Published: July 2006

High-yield synthesis of pure oxo(phthalocyaninato)titanium(IV) was conveniently achieved by heating a mixture of 1,2-dicyanobenzene, titanium(IV) butoxide, urea, and 1-octanol at 150 °C. It is suggested that a key pathway of the efficient condensation reaction is the complex formation of titanium(IV) butoxide with ammonia generated by the nucleophilic attack of 1-octanol to urea. Applicabilities of this method were investigated for condensation reactions of 1,2-dicyanobenzene with other metal alkoxides.
Enzyme Reactions in Microstructured Media. Subtilisin Catalysis in Alkyl Glucopyranosides Aggregates
Authors: Kunugi Shigeru , Hayashi Yuuji , Koyasu Akira , Tanaka Naoki , Shiraishi Makoto
Published: July 2006

In order to understand the effect of the structures of the surrounding medium on biocatalytic reactions, hydrolytic catalysis by subtilisin Carlsberg in a ternary system containing octyl β-D-glucopyranoside (β-OG), water, and octanol (OcOH) was studied, with special reference to the enzyme reactivity and the morphology of the surfactant aggregates.

First, the effect of β-OG and other alkyl D-glucopyranosides (AG) on the subtilisin reaction was studied in the surfactant/water binary system; all four surfactants tested were found to inhibit the subtilisin catalysis.

Then, a detailed phase diagram of β-OG/water/octanol was determined and several liquid crystalline phases were found.

When the subtilisin reactions were measured in several compositions in the phase diagram, the maximum of the apparent rate was observed in reversed micells as well as in the reversed hexagonal phase at a certain [water]/[surfactant] ratio (wo). The apparent optimal wo was calculated to be around 5—6. These results were compared with the results in another ternary system of Aerosol OT/water/isooctane.
Deuterated Derivatives of 3,5-Dimethyl-1-(4-nitrophenyl)pyrazole for Nonlinear Optical Materials
Authors: Okazaki Masaki , Uchino Nobuhiko , Nozaki Nobuharu , Kubo Kazumi
Published: July 2006

A weak absorption of laser light by a nonlinear optical crystal causes a noticeable temperature rise in the crystal. Such absorption may undesirably shift the reflactive indices (some optical characteristics) of the crystal. 3,5-dimethyl-1-(4-nitrophenyl)pyrazole [DMNP], an excellent nonlinear optical material, was deuterated in order to suppress its absorption in the 1 μm wavelength region.

Three deuterated deriatives were synthesized; their crystal structures were identical with that of DMNP. The deuteration of the pyrazole part including the two methyl moieties proved to be more effective than deuteration of the phenyl part (benzene ring) with regard to a reduction of the IR absorption.

A good correlation was confirmed between the temperature elevation under laser irradiation and IR absorption.
Recent Topics on Functionalization and Recognition Ability of Calixarenes: The ‘Third Host Molecule’
Authors: Takeshita Michinori , Shinkai Seiji
Published: July 2006

This review article covers recent topics of a calixarene family concerning their stereochemistry, complexation with metal ions and organic guests, and other topics. As stereochemistry of calixarenes, the restriction of flipping motions of the composed benzene units of calix[4]-, [5]-, [6]arenes is summarized. In Recognition of Calixarenes, the selective recognition of alkali metal cations utilizing calixcrowns is a main subject in metal cation recognition. Concerning with recognition of metal cations and organic molecules, the ‘reading-out’ systems of recognition phenomena are summarized. The complexation of calix[8]arene with fullerene, which was discovered as serendipity and will be very useful as a new fullerene purification method is also reported.
Crystal Structures and Electrical Resistivities of Three-Component Organic Conductors: (BEDT-TTF)2MM′(SCN)4 [M = K, Rb, Cs; M′ = Co, Zn, Cd]
Authors: Mori Hatsumi , Tanaka Shoji , Mori Takehiko , Maruyama Yusei
Published: July 2006

New three-component organic conductors, (BEDT-TTF)2MM′(SCN)4 [M = K, Rb, Cs; M′ = Co, Zn, Cd], are prepared. The crystal structure analyses of α-ET2CsCo(SCN)4, ETZn(SCN)3, α-ET2RbZn(SCN)4, α-ET2CsZn(SCN)4, α-ETCd0.66(SCN)2, and ET2CsCd(SCN)4 are carried out. Most of salts have the α-type donor arrangement and the polymer sheet like [···M′2+···(SCN)−···M+···] in a thick anion layer. Especially α-(BEDT-TTF)2CsM′(SCN)4 [M′ = Co and Zn] are metallic down to 20 K.
Generation, Isolation, ESR and 1H ENDOR Spectra, and Magnetic Characterization of N-[(4-Nitrophenyl)thio]-2-t-butyl-1-pyrenylaminyl
Authors: Miura Yozo , Oka Hiroyuki , Yamano Eiji , Teki Yoshio , Takui Takeji , Itoh Koichi
Published: July 2006

The oxidation of N-[(4-nitrophenyl)thio]-2-t-butyl-1-aminopyrene yielded a quite persistent and oxygen-insensitive N-[(4-nitrophenyl)thio]-2-t-butyl-1-pyrenylaminy radical (3), which was isolated as reddish-black fine needles. The hyperfine coupling (hfc) constants for the aminyl were determined by ESR and 1H ENDOR measurements, indicating that there is an extensive delocalization of the unpaired electron from the nitrogen onto the pyrene ring. A comparison of the hfc constants with structurally close N-[(4-nitrophenyl)thio]-7-t-butyl-1-pyrenylaminyl (1) and N-[(4-nitrophenyl)thio]-2,7-di-t-butyl-1-pyrenylaminyl (2) showed that although the spin-density distribution of 3 is similar to that of 2, it is greatly different from that of 1. Magnetic susceptibility measurements of 3 in solid radical crystals showed that the magnetic interaction between the radical spins is strongly antiferromagnetic, giving J/k = −108 and −192 K for 2 and 3, respectively.
Preparation of Some Multifunctionalized Methylenephosphines by Reactions of Chloro[(2,4,6-tri-t-butylphenyl)phosphinidene]methyllithiums with Carbonyl Compounds
Authors: Yoshifuji Masaaki , Ito Shigekazu , Toyota Kozo , Yasunami Masafumi
Published: July 2006

Either a (Z)- or (E)-chloro(phosphinidene)methyllithium reagent, prepared from dichloromethylene- or (E)-chloromethylene-phosphine with butyllithium, respectively, reacted with carbonyl compounds to give the corresponding functionalized methylenephosphines. Although the stereochemistry of the products was retained during the initial step of the reaction, in some cases E/Z isomerization reactions occurred to the resulting methylenephosphines. Imidazolidinediones bearing the P=C bond were obtained for the first time by a reaction of the E-lithium reagent with phenyl isocyanate; the structure of the Z-isomer was determined by X-ray analysis.
Direct Determination of the Intermolecular Pair-Potential Energy Function of Methane from the Extended Principal of the Corresponding States
Authors: Goharshadi Elaheh K , Boushehri Ali
Published: July 2006

The pair-potential energy function for methane has been determined using a direct inversion of the experimentally reduced viscosity collision integrals obtained from the corresponding-states correlation. The potential obtained in this way is in reasonable agreement with the potential independently known from the crossed molecular-beam technique.
Kinetics and Mechanism of the High-Temperature Selenidization of Titanium
Authors: Naruke Haruo , Yamada Kenji , Kakegawa Kazuyuki , Sasaki Yoshinori
Published: July 2006

A titanium sheet was selenidized in selenium vapor of 1.33—13.33 kPa at 823—973 K by means of a sealed-tube method. X-Ray diffraction patterns and an electron-probe microanalysis of the product films showed the layer to comprise only TiSe2. Since the selenidization obeyed a parabolic rate law under all of the conditions employed, the rate-determining step was a diffusion process. The parabolic rate constant (Kp) could be expressed as a function of the absolute temperature, and was approximately proportional to the partial pressure of Se2. A marker experiment indicated that selenium was the component which diffused in the product film.
Kinetics and Mechanisms of Photoinduced Reduction of Methylviologen by N-Alkyltetraphenylporphyrinatozinc(II) in Methanol
Authors: Tsukahara Keiichi , Sawai Naoko , Hamada Satoko , Nakazawa Takashi , Nakagaki Ryoichi
Published: July 2006

N-3-Bromopropyl-5,10,15,20-tetraphenylporphyrinato(1-)chlorozinc(II), [Zn(BrPrtpp)Cl], catalyzed the formation of a methylviologen radical cation (MV+•) on steady-state irradiation of degassed methanol solutions with visible light (>420 nm) in the presence of triethanolamine (TEOA). The initial rate (Vi) of the formation of MV+• was of first order in the concentration of MV2+ and in the intensity of light and was independent of the concentration of TEOA above 0.025 M. Plots of Vi vs. the concentrations of [Zn(BrPrtpp)Cl] were curved. The fluorescence of [Zn(BrPrtpp)Cl]*, whose lifetimes are τ1s = 0.7 ns (48%) and τ2s = 2.0ns (52%) in methanol at 25 °C, was not quenched by MV2+. The excited triplet state of [Zn(BrPrtpp)Cl] (τ0t = 3.2 μs in MeOH) was efficiently quenched by MV2+ (kq = (6.0 ± 0.6) × 107 M−1 s−1 at 25 °C, 1 M = 1 mol dm−3). The thermal back electron-transfer reaction between [Zn(BrPrtpp)Cl]+• and MV+• was also observed (kb = (1.2 ± 0.2) × 1010 M−1 s−1). On the basis of the steady-state irradiation kinetics and ns-laser flash photolysis, the quantum yield of the excited triplet state of [Zn(BrPrtpp)Cl] can be evaluated to be 0.98 ± 0.02. [Zn(BrPrtpp)Cl] was found to be a more effective photocatalyst than [Zn(Prtpp)Cl] (HPrtpp = N-propyl-5,10,15,20-tetraphenylporphyrin) or [Zn(tpp)] (H2tpp = 5,10,15,20-tetraphenylporphyrin) under the present experimental conditions.
Preparation and Chemical Reactions of Trifluoroacetaldehyde Azine (1,1,1,6,6,6-Hexafluoro-3,4-diaza-2,4-hexadiene)
Authors: Hashidzume Akihito , Kajiwara Atsushi , Harada Akira , Kamachi Mikiharu , Kusunoki Masami
Published: July 2006

Trifluoroacetaldehyde azine (TFAcAz) was prepared and its reactivity was investigated. TFAcAz is readily attacked by nucleophiles such as trialkylamines, methanol, and water. The structures of the products were studied by 1H, 13C, and 19F NMR, IR, Raman, and EI–mass spectroscopies and X–ray crystallographic analysis. A cyclic dimer containing a 1,4-dihydro-1,2,4,5-tetrazine ring was obtained by the reactions of TFAcAz with trialkylamines. 1,2-Adducts were found to be produced by the reactions of TFAcAz with methanol and with water.
Formalized Drawing of Fullerene Nets. 1. Algorithm and Exhaustive Generation of Isomeric Structures
Authors: Yoshida Mitsuho , Osawa Eiji
Published: July 2006

A simple formalism for unfolding the fullerene structure onto a planar lattice is proposed. We recommend using deltahedra containing twelve penta-coordinated vertices as the geometrical precursors of fullerenes, and unfolding them onto a planar lattice according to Dürer’s style. This old style has several unique features that allow a priori drawing of diagrams that fold to fullerenes. Combined with the known algorithm for generating approximate atomic coordinates from the connectivity, which can be readily read off from the net diagram, the present method provides an alternative way of exhaustive generation of isomeric fullerene structures.
Asymmetric Synthesis of a β-Lactam Framework via the Conjugate Addition of Amidocuprates(I) to Chiral Enoates
Authors: Asao Naoki , Uyehara Tadao , Tsukada Naofumi , Yamamoto Yoshinori
Published: July 2006

Amidocuprate(I) reagents {Li[Cu(NR2)2]} and higher order cyanocuprates(I) {Li2[Cu(CN)(NR2)2]} have been developed as a new class of nitrogen nucleophiles. These reagents underwent regioselective 1,4-additions to α,β : γ,δ-dienoates, whereas NHR2 gave a 1,6-addition product and the lithium reagent LiNR2 afforded a mixture of 1,4- and 1,2-addition products. The amidocuprates(I) were added to chiral α,β : γ,δ-dienones having a 8-phenyl-p-menth-3-yl or a 10,2-bornanesultam chiral auxiliary in order to produce 1,4-adducts in good to high diastereoselectivity. The addition of Li[Cu{N(Bn)(TMS)}2] and Li2[Cu(CN){N(Bn)(TMS)}2] to 8-phenyl-p-menth-3-yl 5-phenyl-2,4-pentadienoate or N-(5-phenyl-2,4-pentadienoyl)-10,2-bornanesultam produced an (R)-chirality at the β-position. The 1,4-addition of Li2[Cu(CN){N(Bn)(TMS)}2] to the bornanesultam, followed by trapping with acetaldehyde, gave the α-(1-hydroxyethyl)-β-amino derivative as a single isomer in good yield. This three-component coupling was used in an asymmetric synthesis of a β-lactam.
Volume Study on the Micelle Formation of Local Anesthetic Dibucaine Hydrochloride and Dodecyltrimethylammonium Chloride Mixtures
Authors: Yamanaka Michio , Matsuki Hitoshi , Kaneshina Shoji
Published: July 2006

Densities of aqueous solutions of mixtures of dibucaine hydrochloride (DCHC), a local anesthetic, and dodecyltrimethylammonium chloride (DTAC) were measured as functions of total molality. The apparent molar volumes of the mixtures were calculated from the density data. The molar volumes in the monomeric and micellar states were evaluated from the dependence of the apparent molar volume on the total molality. The critical micelle concentration (cmc) of the mixtures was determined from the break point of the apparent molar volume vs. the total molality curves, while the micellar composition was evaluated from the dependence of the cmc on the mole fraction of DTAC in the mixture. The composition diagram of micellization has a swollen cigar shape, slightly distorted in the composition range near the DTAC component; such a distortion indicates slightly non-ideal mixing between the hydrophobic groups of DCHC and DTAC molecules in the micelle. However, the molar volume of micellar state varies depending upon the micellar composition along a straight line connecting the molar volumes of DCHC and DTAC. Moreover, the volume of micelle formation is smaller for DCHC, which has larger monomer and micellar volumes than DTAC, and increases linearly with increasing DTAC composition in the micelle. Therefore, the bulky structure of the hydrophobic part of the DCHC molecule affects both the miscibility and the volume behavior in the DCHC–DTAC mixed micelles.
Kinetics of Polymerization of Acrylamide in Aerosol OT W/O Microemulsions
Authors: Kawai Takeshi , Yasuda Yoichi , Kon-no Kijiro
Published: July 2006

Time dependence of the conversion of acrylamide (AAm) initiated with potassium peroxodisulfate (KPS) was examined at various [AAm] and [KPS] in W/O microemulsions of 1,4-bis(2-ethylhexyl) sodium sulfobutanedioate in cyclohexane media at 45 °C. The rate of polymerization (Rp) calculated from the conversion-time profiles yielded the following equation: Rp ∝ [AAm]1.0[KPS]0.5. From these values of reaction orders for AAm and KPS, it was found that the polymerization of acrylamide in W/O microemulsions can be regarded as normal radical polymerization and biradical termination between polymer radicals.
Solubilization of Water-Insoluble Dyes by Polyion/Surfactant Complexes
Authors: Hayakawa Katumitu , Shinohara Satoshi , Sasawaki Shin-ichiro , Satake Iwao , Kwak Jan C T
Published: July 2006

Solubilization data for the water-insoluble dyes o-(2-amino-1-naphthylazo)toluene (OY) and 1-pyrenecarbaldehyde (PyA) in mixed solutions of anionic polyelectrolyte and a cationic surfactant are reported. The polymers used were sodium dextran sulfate (DxS) and the sodium salt of poly(styrenesulfonic acid) (PSS). The surfactants used were dodecyltrimethylammonium bromide (DTAB) and tetradecyltrimethylammonium bromide (TTAB). DxS exhibited a highly cooperative binding of the surfactant ions, while binding to PSS occured at lower surfactant concentrations, but was less cooperative. DxS/surfactant complexes had a larger solubilization capacity per bound surfactant ion for both OY and PyA than did PSS/surfactant complexes. The standard Gibbs energy changes for solubilization in DxS/DTAB were determined to be 4.0 kJ mol−1 for OY and 5.4 kJ mol−1 for PyA; the values in PSS/DTAB were 6.5 kJ mol−1 for OY and 9.3 kJ mol−1 for PyA. The solubilization capacities and standard Gibbs energy changes of polyion/surfactant complexes strongly relate to the binding mode of the surfactant. The differences in the solubilization capacities and standard Gibbs energy changes between polyion/surfactant complexes and DTAB or TTAB micelles, and between OY and PyA, are discussed in relation to the aggregate size and solubilizate location.
Ab initio Classical Trajectory Calculations: Application to Four-Centered HF Elimination from Vinyl Fluoride
Authors: Takayanagi Toshiyuki , Yokoyama Atsushi
Published: July 2006

Classical trajectories for four-centered HF elimination from vinyl fluoride have been calculated directly from ab initio molecular orbital results at the HF/3-21G level of theory, without the construction of an analytical potential energy function. The excess energy dependences of the product energy distributions and vector correlations were calculated. The calculated results were compared with available experimental data and qualitative agreements were obtained. However, in order to obtain quantitative agreements, trajectory analyses at a more accurate ab initio level of theory seem to be necessary.