bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Calorimetric Study on the β′ Phase in the System Tin–Antimony. Enthalpies of Mixing and Formation
Authors: Badawi Walid Ahmad 
Published: July 2006

Abstract
Calorimetric studies on the behavior of the enthalpy of formation at 573 K in the system tin–antimony have been carried out at the compositions 44, 50, 57 at-% Sb using a presently constructed calorimeter. The enthalpy of mixing at 943 K has been determined in the whole range of composition. The relation of the behavior of mixing to that of formation is found as predicted earlier. The enthalpy of formation displays a pronounced temperature dependence above 623 K. The thermodynamic properties of the alloy SnSb at the three compositions exclude a transformation from β to β′ phase around 600 K. Also estimated entropy terms indicate the absence of such a transformation. Earlier reported additional β phase in the system Sn–Sb seemed therefore not to be present.
On the Intrinsic Difference between Topological Aromaticity and So-Called Quasi-Aromaticity
Authors: Ichikawa Hiroshi , Aihara Jun-ichi , Daehne Siegfried 
Published: July 2006

Abstract
In an attempt to understand the intrinsic difference between topological aromaticity and so-called quasiaromaticity, the authors examined the potential energy and the kinetic energy of electrons in 6-π-acyclic polymethine-like molecules (5–7), benzene (8), and hexatriene (9) as a reference structure. Protonation interrupts π conjugation; the energetic difference from the non-protonated structure depends on the conjugative stabilization energy. Such a difference from the reference system corresponds to extra stabilization. Analysis of this difference showed that benzene increases the kinetic energy by interrupting its conjugation more than hexatriene while polymethine-like molecules increase the potential energy by doing so. This indicates that extra stabilizaion in benzene is produced by lowering the kinetic energy of electrons. In marked contrast with this that in polymethine-like molecules is due to lowering the potential energy. Analogous results were obtained in the ten-π-electron systems (10–13). The authors discussed the inappropriateness of the term “quasi-aromatic” for polymethinic resonance stabilization.
A Modified Vapor Saturation Method for Preparing Aqueous Solutions of Solid Aromatic Hydrocarbons
Authors: Sanemasa Isao , Ishibashi Kazunari , Kumamaru Masaya , Deguchi Toshio 
Published: July 2006

Abstract
An excess quantity of a solid hydrocarbon is dispersed in water, and then air is bubbled through the aqueous phase to produce the solute vapor. The vapor is introduced into a separate water phase and circulated in a closed system. Aqueous solutions saturated with some solid aromatic hydrocarbons can be prepared in a relatively short time without any need to remove solute microcrystals. It can be confirmed whether the solubility obeys Henry’s law. The present method provides us with rough enthalpy of sublimation of a solute if its solubility follows Henry’s law. Biphenyl, naphthalene, phenanthrene, and anthracene were examined as solutes.
Implications of Unusual Population Ratios in Rotational Isomers of 9-(4-Substituted Benzyl)-8,13-dichloro-1,4-dimethyltriptycenes and 4-Substituted 9-Benzyl-8,13-dichloro-1-methyltriptycenes: CH3···π Hydrogen Bond
Authors: Nakai Yasufumi , Inoue Katsuya , Yamamoto Gaku , Oki Michinori 
Published: July 2006

Abstract
Population ratios of rotational isomers in substituted 9-benzyl-8,13-dichloro-1-methyltriptycenes were examined by equilibration in solution. The sc isomers increase in their populations as the electron density on the 9-benzyl group increases and the acidity of the 1-methyl group increases. The sc/ap ratios were larger than 2, the statistical value, in all the compounds examined, except the 4-nitrobenzyl compound. By contrast, MM2 calculations show that the sc isomers are less stable than the ap by ca. 1 kcal mol−1. This discrepancy together with the substitutent effects on populations of the rotamers are attributed to the presence of CH3···π interactions in the sc forms that stabilize the system mainly by charge-transfer interactions but are not included in the MM2 calculations.
Catalytic Intermolecular Hydrogen Transfer with Photogenerated Hydride Transient CoH[PPh(OEt)2]3
Authors: Onishi Masayoshi , Matsuda Masahiko , Takaki Isato , Hiraki Katsuma , Oishi Shigero 
Published: July 2006

Abstract
Pyrex-filtered photoirradiation of a thermally inert complex CoH[PPh(OEt)2]4 generated a coordinatively unsaturated active hydride species “CoH[PPh(OEt)2]3” (CoHP3), which catalyzed hydrogen transfer from secondary alcohols to carbonyl compounds, such as ketones. Study of initial reaction-rate dependence of the hydrogen transfer on complex and substrate concentrations indicated that the reaction was initiated by coordination of the carbonyl compounds to the photogenerated CoHP3 species, and these coordination was confirmed by the decay analysis of the transient CoHP3 absorbance observed after laser flash photolysis. In addition, the rate-determining step of the hydrogen-transfer reaction was associated with the hydride transfer to the carbonyl carbon, at the stage of the transformation of hydrido (ketone or aldehyde) cobalt into alkoxo intermediate. Second-order coordination-rate constants k′ of aldehydes and ketones to CoHP3 ranged from 105 to 108 M−1 s−1. The constants k′ of aldehydes were considerably larger than those of ketones, where substantial steric repulsion by the bulky substituents introduced in place of the aldehyde hydrogen, was presumed to hinder the CoHP3 approach to the carbonyl group.
A New and Convenient Synthesis of 1α,25-Dihydroxyvitamin D2 and Its 24R-Epimer
Authors: Tsuji Masahiro , Yokoyama Shinji , Tachibana Yoji 
Published: July 2006

Abstract
1α, 25-Dihydroxyvitamin D2 (1a) was synthesized by irradiation and subsequent thermal isomerization of (22E)-5,7,22-ergostatriene-1α,3β,25-triol (16a). The triol 16a was obtained via 22-oxo-5α,8α-(4-phenyl-3,5-dioxo-1,2,4-triazolidine-1,2-diyl)-23,24-dinor-6-cholene-1α,3β-diyl diacetate (12) starting from (22E)-5,7,22-ergostatriene-1α,3β-diyl diacetate (10), a precursor of 1α-hydroxyvitamin D2. Introduction of the new side chain with the desired stereochemistry was carried out selectively by the reductive elimination of the β-hydroxy sulfone derived from the C-22 aldehyde (12) and an optically active sulfone, prepared via (S)-2,3-dimethyl-1,3-butanediol from methyl (S)-3-hydroxy-2-methylpropionate. Similarly a C-24 epimer of 1a was synthesized.
A Synthesis of Unsymmetric Porphyrin Dimers
Authors: Maruyama Kazuhiro , Nagata Toshi , Ono Noboru , Osuka Atsuhiro 
Published: July 2006

Abstract
A new synthetic method of porphyrins via bis(hydroxymethyl)dipyrromethanes is described. This new method can be utilized for preparation of several unsymmetric porphyrin dimers.
Adsorption of Poly(methyl methacrylate) on Silica Surfaces Having Various Silanol Densities
Authors: Kobayashi Kazutoshi , Araki Kazuo , Imamura Yoshio 
Published: July 2006

Abstract
The adsorption of poly(methyl methacrylate) (PMMA) on silica surfaces having various silanol densities was studied by ESR and IR spectroscopies. Three silica samples, Nipsil HD, Aerosil 300, and Aerosil R812, which have 8, 2.2, and 0.54 nm−2 silanol densities, respectively, were used as the adsorbents. The amount of adsorption, A, the surface coverage, θ, and the fraction of train segments in the polymer, p, were determined. The values of the segment fractions anchoring through the hydrogen bond in all train segments of the adsorbed polymer, fHB, were also estimated. When PMMA adsorbed on Nipsil HD, the polymer adsorbed predominantly by the formation of hydrogen bonds; on the other hand, when PMMA adsorbed on Aerosil 300, the polymer adsorbed through the hydrogen bond in the part of 30–40%. When PMMA adsorbed onto Nipsil HD, the value of pESR obtained by the ESR method was almost the same as the pIR obtained by the IR method. When PMMA adsorbed onto Aerosil 300, the value of pESR was 0.47, twice the value of pIR(0.24).
The Conformational Interconversion of 1,3-Diamine Chelate: Tetracyano(1,3-propanediamine)ferrate(III)
Authors: Kuroda Yoshitaka , Goto Masafumi , Sakai Tomoya 
Published: July 2006

Abstract
The activation parameters for the chair-to-chair interconversion of the six-membered chelate ring of [FeIII(CN)4(1,3-propanediamine)]− have been determined from a line-shape analysis of the 1H NMR spectra of the paramagnetic complex by taking advantage of the large differences in the chemical shift: ΔH≠=32.2±4.6 kJ mol−1, ΔS≠=31.2±28.6 J mol−1 K−1, and ΔG298≠=22.9±3.9 kJ mol−1. The ΔH≠ and ΔS≠ values are larger by 7.5 kJ mol−1 and 31 J mol−1 K−1 than those of the corresponding 1,2-ethanediamine chelate, [FeIII(CN)4(1,2-ethanediamine)]−, respectively. The kinetic data supported the transition state with a half-boat conformation.
Polar and Dipolar Substituent Effects and Transition State in the Reaction between Substituted Anilines and Nitrosobenzene. An Evaluation of Ortho and Electrostatic Effects
Authors: C. Schmitt Carla , A. Moritz Carlos , G. Pizzolatti Moacir , A. Yunes Rosendo 
Published: July 2006

Abstract
The rate constants of the hydronium catalyzed attack of substituted anilines on nitrosobenzene, to give azobenzene, exhibit a large dependence on the substituent constant σ− (ρ−=−1.92). The relatively high value of ρ− compared to that obtained from the equilibrium of protonation of anilines (ρ−=−2.77) and the solvent effect on the rate constants support the idea that the transition state involves a large amount of nitrogen–nitrogen bond formation and therefore a strong charge development on the nitrogen and oxygen of the amino and nitroso groups, respectively. A good correlation between basicity and nucleophilic reactivity is obtained by the Brönsted equation (β=0.65, r=0.988) for the para and meta dipolar substituents. Aminobenzoates show a significantly higher reactivity than that calculated from the Brönsted line and this is attributed to an electrostatic participation of the carboxylato group. Nevertheless, this effect is somewhat compensated by repulsion between the carboxylato and the negatively charged oxygen of the nitroso group.
Polyazamacrocycles. V. Structure of Isomeric 3,5,7,7,10,12,14,14-Octamethyl-1,4,8,11-tetraazacyclotetradecanes
Authors: Bembi Ramesh , M. Sondhi Sham , K. Singh Ashok , K. Jhanji Amrit , G. Roy Tapashi , Lown J William , Ball R G 
Published: July 2006

Abstract
Reduction of 3,5,7,7,10,12,14,14-octamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene (Me8[14]diene) with sodium borohydride yields three diastereomeric Me8[14]anes. These diastereomers can be separated through fractional crystallization from xylene. The structure of these isomers has been established on the bseis of their NMR spectra. The structure of one isomer has been confirmed by X-ray crystallography.
Systematic Enumerations of Highly Symmetric Cage-Shaped Molecules by Unit Subduced Cycle Indices
Authors: Fujita Shinsaku 
Published: July 2006

Abstract
Cage-shaped hydrocarbons are enumerated, starting from the tetrahedron skeleton (Td symmetry). This enumeration stems from an edge strategy in which six edges of the skeleton are substituted by m methylene and n ethylene units. This is accomplished by a new method based on unit subduced cycle indices. This is a versatile methodology for counting cage-shaped hydrocarbons that have a given subsymmetry and an index term, xmyn, the latter of which corresponds to the molecular formula C4+m+2nH4+2m+4n.
1H and 79Br NMR in 1,4-Didecyl-1,4-diazoniabicyclo[2.2.2]octane Dibromide and Diiodide
Authors: Nakayama Hirokazu , Eguchi Taro , Nakamura Nobuo , Chihara Hideaki , Nogami Takashi , Imamura Kengo , Shirota Yasuhiko 
Published: July 2006

Abstract
Temperature dependence of 1H NMR spin-lattice relaxation time was measured in solid 1,4-didecyl-1,4-diazoniabicyclo[2.2.2]octane dibromide and diiodide (C10–DABCO–C10–Br2 and C10–DABCO–C10–I2). 79Br NMR spin-lattice relaxation time and chemical shift measurements in the high-temperature phase were also performed in C10–DABCO–C10–Br2. It was found that the cation rotates isotropically, while the anion diffuses at a correlation time of ca. 10−8 s in the high-temperature phase of C10–DABCO–C10–Br2. The activation energies for these modes are 30 and 34 kJ mol−1, respectively. Methyl reorientation is activated in the low-temperature phase (Ea=11.8 kJ mol−1 in C10–DABCO–C10–Br2 and Ea=12.0 kJ mol−1 in C10–DABCO–C10–I2). Near the phasetransition temperature some motion of decyl chain is observed (Ea=57 kJ mol−1 in C10–DABCO–C10–Br2 and Ea=35.5 kJ mol−1 in C10–DABCO–C10–I2).
3d-Element Coordination Compounds with Bidentate Sulfur-Containing Ligands as Possible Carriers of Non-Silver Photographic Images
Authors: Mikhailov O V , Budnikov G K 
Published: July 2006

Abstract
Complexing processes occurring between reactive matrices obtained from Fe(III), Co(III), Ni(II), Cu(II) hexacyanoferrates(II), and alkaline solutions of various nitrogen-sulfur-containing chelating ligands in thin gelatin layers have been studied. With Fe(III) and Cu(II) hexacyanoferrates, complexing process is found out to proceed according to SN1 mechanism, while in Co(III) and Ni(II) hexacyanoferrates matrices, SN2 mechanism is realized. The schemes of the processes proceeding in each of the above matrices are given. The examples of the kinetic curves for particular systems “hexacyanoferrate(II)-ligand” as well as spectral characteristics of thin gelatin layers containing chelate complexes formed as a result of the chelating process are presented. The possibility of practical utilization of complexing processes studied for obtaining non-silver photographic images from light-resistant metallorganic dyes is reported.
The Molecular Structure of the Heterodinuclear Organometallic Complex of Platinum and Tungsten, Phenyl(1,5-cyclooctadiene)platinum–tricarbonyl(η5-cyclopentadienyl)tungsten
Authors: Miki Kunio , Kasai Nobutami , Endo Isao , Komiya Sanshiro 
Published: July 2006

Abstract
The structure of the novel heterodinuclear organometallic complex, [(cod)(Ph)Pt–W(CO)3(η5-C5H5)] has been determined by X-ray crystallography; the Pt–W bond distance is 2.844(1)Å.
A Mild Selective Monobromination Reagent System for Alkoxybenzenes; N-Bromosuccinimide–Silica Gel
Authors: Konishi Hisatoshi , Aritomi Katsutomo , Okano Tamon , Kiji Jitsuo 
Published: July 2006

Abstract
The monobromination of alkoxybenzenes with N-bromosuccinimide catalyzed by silica gel in carbon tetrachloride occurred preferentially at the para-position. m-t-Butylmethoxybenzene yielded 4-bromo-3-t-butyl-1-methoxybenzene with a selectivity of 74% even in the presence of a bulky substituent at the meta-position.
Acid-Catalyzed Oxidation of Oxiranes with Dimethyl Sulfoxide Giving α-Hydroxy Ketones
Authors: Tsuji Tadakazu 
Published: July 2006

Abstract
The reaction of various oxiranes with dimethyl sulfoxide in the presence of Molecular Sieve 4A and acid afforded the corresponding α-hydroxy ketones. The molecular sieve was found to accelerate the reaction.
Formulation and Enumeration of Five-Center Organic Reactions
Authors: Fujita Shinsaku 
Published: July 2006

Abstract
Five-center organic reactions are formulated in the form of pentagonal reaction-center graphs (RCC’s) that are subgraphs of imaginary transition structures. This formulation is based on the concept of a charge space that affords rational representations of coordinate bonds. Pólya’s theorem is applied to the enumeration of these RCG’s, in which the obligatory minimum valencies of vertices restrict the mode of substitution.
AN IMPROVED CNDO APPROACH TO THE 1H CHEMICAL SHIFTS OF OLEFINIC COMPOUNDS
Authors: Kajimoto Okitsugu , Fueno Takayuki 
Published: July 2006

Abstract
A theoretical expression has been derived for the magnetic shielding constant of aliphatic hydrogens, without using the customary point dipole approximation. The expression, combined with CNDO/2 electron densities, has correctly reproduced the 1H chemical shifts observed for various substituted ethylenes and butadienes. It is concluded that the diamagnetic shielding from the neighboring carbon constitutes an important contribution to the shifts.
CORRELATION OF 13C–H AND 13C–C–H COUPLING CONSTANTS OF THE FORMYL GROUP IN SUBSTITUTED BENZALDEHYDES WITH HAMMETT σ CONSTANTS
Authors: Inamoto Naoki , Masuda Shozo , Terui Atsuko , Tori Kazuo 
Published: July 2006

Abstract
The values of 13C–H and 13C–C–H coupling constants of the formyl group in substituted benzaldehydes followed the Hammett equation. The ρ(JC–H) value was found to be considerably larger than that for substituted toluenes. Values for ρo (JC–H) and ρo(JC–C–H) are also discussed.
SPIN TRAPPING BY USE OF NITROSO COMPOUNDS. III. PHENOXAZlNE-N-OXYL PRODUCED FROM THE PHENOXY RADICAL BY SPIN TRAPPING
Authors: Terabe Shigeru , Kuruma Kazuo , Konaka Ryusei 
Published: July 2006

Abstract
Phenoxazine-N-oxyl was produced from the phenoxy radical in the ESR spin trapping technique using nitrosobenzene, and the mechanism of formation was deduced from the results of trapping using deuterated compounds and by product analysis.
INTRAMOLECULAR FORMATION OF YLIDES FROM CARBENES BEARING SULFUR ATOM ON γ-POSITION
Authors: Kondo Kiyosi , Ojima Iwao 
Published: July 2006

Abstract
The thermal decomposition of a sodium salt of 4-phenylthio-4-methyl-2-pentanone tosylhydrazone in diglyme at 150–160°C afforded a mixture of 1,2,2-trimethylcyclopropyl phenyl sulfide (17%), 2,2,3a-trimethyl-1,2,3,3a-tetrahydro-1-thiaazulene (9%), and isomeric 4-phenylthio-4-methylpentenes (74%). Analogous mixtures in varying amounts were obtained from tosylhydrazones derived from 4-phenylthio-2-butanone, 3-phenylthiobutyrophenone, and 3-phenylthio-3-methylbutyrophenone.
FARFUGIN A AND B, NEW SESQUITEEPENES FROM FARFUGIUM JAPONICUM
Authors: Nagano Hajime , Moriyama Yoshihiko , Tanahashi Yoshiaki , Takahashi Takeyoshi , Fukuyama Masaru , Sato Kenichi 
Published: July 2006

Abstract
Two new sesquiterpenes, farfugin A and B, isolated from Farfugium japonicum, have been shown to be a tetrahydronaphthofuran derivative (I) and a benzofuran derivative (II), respectively.
STRUCTURES OF SECO-IRIDOIDS FROM LIGSTRUM OBTUSIFOLIUM SIEB. ET ZUCC.
Authors: Asaka Yukihiro , Kamikawa Tadao , Kubota Takashi , Sakamoto Harunari 
Published: July 2006

Abstract
From spectroscopic evidence, the two seco-iridoids ligstro-side and 10-hydroxyligstroside, isolated from Ligstrum obtusifolium Sieb. et Zucc., are assigned the structures (I) and (V), respectively.
MECHANISM OF CHARGE-TRANSFER POLYMERIZATION: DETECTION OF ION-RADICAL INTERMEDIATES IN THE PHOTOSENSITIZED REACTION OF N-VINYLCARBAZOLE IN THE PRESENCE OF p-CHLORANIL
Authors: Shirota Yasuhiko , Kawai Kiyoshi , Yamamoto Naoto , Tada Kazuhiro , Mikawa Hiroshi , Tsubomura Hiroshi 
Published: July 2006

Abstract
Formation of transient ion-radicals in the photosensitized reaction of N-vinylcarbazole with p-chloranil as an acceptor has been demonstrated for the first time by means of flash spectroscopy.
THE PHOTOCHEMICAL AND THERMAL REACTIONS OF DIETHYL PHENYLAZOPHOSPHONATE WITH CYCLOHEXENE
Authors: Nagao Yoshihiro , Shima Kensuke , Sakurai Hiroshi 
Published: July 2006

Abstract
The photochemical and thermal reactions of diethyl phenylazophosphonate with cyclohexene afforded two 1:1 adducts. In the photochemical reaction, there was the wavelength dependence for the formation of the adducts. It was proposed that the active species for the formation of the adducts were different between the thermal and photochemical reactions.
DECOMPOSITION OF DITHIOCARBAMATES. III. ETHYLDITHIOCARBAMIC ACID IN CONCENTRATED SULFURIC ACID SOLUTIONS
Authors: Takami Fumitaka , Wakahara Shigeru , Maeda Takashi 
Published: July 2006

Abstract
The UV spectral changes and decomposition rates of ethyldithio-carbamic acid (I) were investigated in sulfuric acid solutions. The presence of the S-protonated form (IV) was established. The observed first-order rate constants fit with the rate expression, kobs = kK/(h0 + K), derivable from the proposed mechanism, IV\oversetK⇔I \oversetk→ EtNH2 + CS2.
SYNTHESES OF COPPER(I) TRIPHENYLPHOSPHINE COMPLEXES
Authors: Shono Toshiyuki , Fujii Yoshihiko , Shinra Koichiro 
Published: July 2006

Abstract
Bis(triphenylphosphine)acetylacetonato copper(I) and analogous seven copper(I)triphenylphosphine chelates were prepared from various cupric complexes by reducing directly with triphenylphosphine.
A NEW TKEMETHYLENECYCLOBUTMONE
Authors: Toda Fumio , Kataoka Toshiaki 
Published: July 2006

Abstract
2,3-Bis(diphenylmethylene)-4-benzylidenecyclobatanone (VII) was prepared and its spectral data were compared with those of 2,4- (IX) and 3,4 bis(diphenylmethylene) cyclobutanedione (X).
POLAR EFFECTS ON THE CLEAVAGE REACTION OF SILICON-SILICON BONDS OF 1,2-DIARYLTETRAMETHYLDISILANE WITH 1,2-DIBROMOETHANE. STRUCTURE AND REACTIVITY IN SH2 REACTION
Authors: Hosomi Akira , Sakurai Hideki 
Published: July 2006

Abstract
Symmetrically substituted 1,2-diphenyltetramethyldisilane and hexamethyldisilane (the reference substrate) were reacted competitively with 1,2-dibromoethane in the presence of dibenzoyl peroxide at 30.0° with ultraviolet irradiation. The relative rates of bimolecular homolytic substitution increased with increasing electron-releasing power of the substituents, and a ρσ+ relationship was established with ρ=−1.55.
THE β-CIS ISOMER OF ETHYLENEDIAMINE-N,N′-DIACETATO(DIAMMINE)COBALT(III) AND SOME RELATED COMPLEXES
Authors: Kuroda Kashiro 
Published: July 2006

Abstract
The β-cis isomer of ethylenediamine-N,N′-diacetato(diammine)cobalt(III) perchlorate, β-cis-[Co(EDDA)(NH3)2] ClO4·H2O, and the corresponding ethylenediamine complex have been prepared by the reaction between [Co(EDDA)(H2O)2]ClO4 and ammonia or ethylenediamine at 100°C. The β-cis configuration of the isomers has been identified by the electronic absorption spectra and PMR spectra.
THE PREPARATION AND THE ABSORPTION SPECTRUM OF THE cis-DICYANODICARBONATOCOBALTATE(III) COMPLEX
Authors: Fujinami Shuhei , Shibata Muraji 
Published: July 2006

Abstract
The dicyanodicarbonatocobaltate(III) anion has been isolated by the reaction of tricarbonatocobaltate(III) and cyanide as the tris(ethylenediamine)cobalt(III) salt. The geometrical structure of the complex has been determined as cis-form by comparing the absorption spectrum with that of the known related complex. The spectrum showed marked splitting of the first absorption band.
LASER PHOTOLYSIS STUDIES ON THE IONIZATION OF N-VINYLCARBAZOLE IN THE PRESENCE AND IN THE ABSENCE OF ELECTRON ACCEPTORS
Authors: Taniguchi Yoshio , Nishina Yasuzo , Mataga Noboru 
Published: July 2006

Abstract
Formation of solvated ion radicals in the N-vinylcabazole (VCZ)-electorn acceptor system has been studied by means of the laser photolysis and transient photoconductivity as well as transient absorption measurments. Ion radical formation due to the encounter collision between an excited VCZ and electron acceptor has been established.
Molecular Structure of Quadricyclane (Tetracyclo[3.2.0.02,7.04,6] heptane) Studied by Gas Electron Diffraction
Authors: Mizuno Kazumi , Fukuyama Tsutomu , Kuchitsu Kozo 
Published: July 2006

Abstract
The average C–C and C–H bond distances (rg) and the C2–C3–C4 angle in quadricyclane were determined by gas electron diffraction to be 1.529±0.003 Å, 1.103±0.009Å and 98.5±2°, respectively. The molecule was found to have C2v symmetry in equilibrium. A number of nonbonded distances were also determined: C1–C4=2.43 Å, C1–C3=2.50 Å and C1–C6=2.18 Å. This structure is compared with those of norbornane and bicyclo[2.1.0]pentane reported in recent publications.
SELECTIVE CARBON–CARBON BOND FORMING REACTION BY THE USE OF ALLYL 2-PYRIDYL SULFIDE DERIVATIVES—TOTAL SYNTHESIS OF α-cis-BERGAMOTENE
Authors: Narasaka Koichi , Hayashi Masatoshi , Mukaiyama Teruaki 
Published: July 2006

Abstract
A convenient method for the selective formation of α-coupled allylic compounds was established by the alkylation of lithium salt of allylic 2-pyridyl sulfide with organic halide and the successive reductive desulfurization of the α-alkylated allylic sulfide with CuCl2 and LiAlH4. The method was successfully applied to the total synthesis of α-cis-bergamotene.