bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure of a Potent Antithyroid Drug, 6-Propyl-2-thiouracil
Authors: Okabe Nobuo , Fujiwara Takaji , Yamagata Yuriko , Tomita Ken-ici 
Published: July 2006

Abstract
The crystal strure of 6-propyl-2-thiouracil (PTU), an antithyroid drug, has been determined as a 2 : 1 complex with 1,4-dioxane [(C7H10N2OS)2(C4H8O2)]. The crystals are monoclinic, space group P21/a, with a=8.983(5), b=23.706(12), c=4.942(2) Å, β=95.79(3)°, V=1047.1(9) Å3, Z=4, Dx=1.36 Mg m−3, Dm=1.35 Mg m−3, MW=214.29, λ(Cu Kα)=1.5418 Å. Final R=0.098 for 1575 reflexions.
Preparation and Characterization of Cobalt(III)–Phosphine Complexes of the Type [Co(CN)2(acetylacetonate)(L)] (L: Tertiary 2-Aminoethylphosphines, and 1,2- and 1,3-Diphosphines)
Authors: Ohishi Tomoji , Kashiwabara Kazuo , Fujita Junnosuke 
Published: July 2006

Abstract
Four new cobalt(III)–phosphine complexes of the type [Co(CN)2(acetylacetonate)(L)] (L=NH2CH2CH2P(C6H5)2, NH2CH2CH2P(CH3)2, (C6H5)2PCH=CHP(C6H5)2, and (C6H5)2PCH2CH2CH2P(C6H5)2) were prepared. The geometrical structures of the 2-aminoethylphosphine, and 1,2- and 1,3-diphosphine complexes were assigned to have trans(C,N) and cis configurations, respectively on the basis of the 1H and 13C NMR spectra.
An Improved Synthesis of threo-3-Methyl-d-cysteine
Authors: Wakamiya Tateaki , Fukase Koichi , Shimbo Kuniaki , Shiba Tetsuo 
Published: July 2006

Abstract
Synthesis of threo-3-methyl-d-cysteine, a moiety of β-methyllanthionine as a component of the peptide antibiotics nisin and subtilin, was achieved via (2R,3R)-1-t-butoxycarbonyl-3-methyl-2-aziridinecarboxamide derived from d-threonine. An addition of thioacetic acid or thiobenzoic acid to the aziridinecarboxamide gave S-acyl-β-mercapto-α-amino acid amide derivatives which were hydrolyzed directly or after the preformation of disulfide bond to afford the desired amino acid.
Penicillin-Cephalosporin Conversion. VII. An Improved Synthesis of 3-Methylenecephams
Authors: Torii Shigeru , Tanaka Hideo , Siroi Takashi , Madono Tomoyuki , Saitoh Norio , Sasaoka Michio , Nokami Junzo 
Published: July 2006

Abstract
Efficient conversion of 2-(7-oxo-2,6-diaza-4-thiabicyclo[3.2.0]hept-2-en-6-yl)-3-chloromethyl-3-butenoates (4), derived from natural penicillins, into 3-methylenecephams (1) has been performed by a simple two-step operation, which comprises replacement of the allylic chlorine atom of 4 with iodine and subsequent acid-catalyzed hydrolysis, leading to 1 in 70–54% overall yields. In the latter step, the ring opening of the thiazoline moiety and the intramolecular substitution of the iodide with the thiol group proceed simultaneously.
Studies of Inorganic Ion Exchangers. VI. The Formation Region and Dehydration Behavior of Various Titanium(IV) Bis(hydrogenorthophosphate) Hydrates
Authors: Kobayashi Etsuro , Yamazaki Shinsuke 
Published: July 2006

Abstract
The formation region, dehydration behavior, and lattice constants of various types of titanium(IV) bis(hydrogenorthophosphate) hydrates were investigated. α-Ti(HPO4)2·H2O was formed by refluxing an amorphous titanium phosphate (ATP) with H3PO4 at 110–165 °C or by treating it with H3PO4 (up to 11.5 mol dm−3) under hydrothermal conditions at temperatures up to 250 °C. (β-γ)-Ti(HPO4)2·xH2O was obtained by refluxing ATP with H3PO4 (15–16 mol dm−3) above 165 °C. γ-Ti(HPO4)2·2H2O was formed by a hydrothermal reaction of ATP and H3PO4 (10–16 mol dm−3) at 200–300 °C. In the thermal analysis of Ti(HPO4)2, no difference in weight loss was found at temperatures up to 920 °C of α-form irrespective of the drying conditions of the samples. The (β-γ)-form dried under reduced pressure over P2O5 had a composition corresponding to that of a 1/2 hydrate. The γ-form dried at a relative humidity of 75% had a composition identical to that of the dihydrate. In view of the X-ray diffraction, it seemed that the (β-γ)-form (11.6 and 9.2 Å) was changed by drying under reduced pressure over P2O5 to the β-form (9.2 Å) as anhydride. The γ-form (11.6 Å) was dehydrated to the β-form by heating. The change in the inter-layer distance upon dehydration was also confirmed by means of a that of the electron diffraction. Thus, it was considered that the (β-γ)-form was a mixture as a quasi stable form.
Stereochemical Aspects of the Optical Resolution of cis(N)-[Co(N)2(O)4]− Complexes by Reversed-phase Ion-pair Chromatography with Cinchona Alkaloid Cations as the Ion-pairing Reagents
Authors: Izumoto Shinji , Sakaguchi Ushio , Yoneda Hayami 
Published: July 2006

Abstract
The reversed-phase ion-pair chromatography with cinchona alkaloid cations as the ion-pairing reagents has been used to resolve optically several anionic complexes of the type cis(N)-[Co(N)2(O)4]−. Complete optical resolution has been achieved for [Co(edta)]−, cis-[Co(ida)2]−, [Co(cydta)]−, [Co(ox)2(en)]−, and cis-α-[Co(ox)(edda)]− by quinine, quinidine, and cinchonidine but not by cinchonine, where edta=ethylenediaminetetraacetate, ida=iminodiacetate, cydta=trans-1,2-cyclohexanediaminetetraacetate, ox=oxalate, en=ethylenediamine, and edda=N,N′-ethylenediaminediacetate. The adjusted retention volumes have been measured for the enantiomers. From comparison of the retention volumes and separation factors obtained for the alkaloids and their derivatives, the mode of chiral discrimination has been proposed.
Preparation and Some Properties of Cobalt(III) Complexes with d-Penicillaminate and Its Derivatives
Authors: Okamoto Ken-ichi , Wakayama Katsuhiko , Einaga Hisahiko , Yamada Shoichi , Hidaka Jinsai 
Published: July 2006

Abstract
Three kinds of [Co(terdentate-N,O,S)2] type complexes were newly prepared; here terdentate-N,O,S denotes d-penicillaminate (d-pen), S-methyl-d-penicillaminate (d-smp) and S-methyl-l-cysteinate (l-smc). Each of the d-smp and l-smc complexes was chromatographically separated into three possible isomers; the d-pen complex was separated into two isomers. These isomers were characterized from their electronic absorption, CD and 1H NMR spectra. Two isomers isolated for [Co(d-pen)2]− were assigned to trans(N) and trans(O), respectively, on the basis of the spectral behavior of the sulfur-to-metal charge transfer band and the reaction with dimethyl sulfate. Three isomers for [Co(d-smp)2]+ were derived from each of two isomers for [Co(d-pen)2]+ by the reaction with dimethyl sulfate. The electronic absorption and CD spectral behaviors are discussed in relation to the comparison of the thioether and thiolato type complexes.
Studies on Long-range Couplings between 77Se and 13C in Some Aryl Selenides, Dichlorides, and Selenoxides. The Inverse Effect on Couplings in the Selenoxide Formation
Authors: Nakanishi War\={o} , Ikeda Yoshitsugu 
Published: July 2006

Abstract
Long-range coupling constants between 77Se and 13C in selenoanisole, diphenyl selenide, diphenyl diselenide, and their 2-mono- and 2,2′-disubstituted derivatives, selenoxanthone, selenanthrene, dichlorides, and selenoxides were measured to disclose predominant factors governing the magnitude of the coupling. Extraordinary large values for two- and three-bond couplings are found in selenoxanthone. Three factors are operative: the orientational effect, the coordination number, and the effect of ring formation. The last factor accompanies a stronger inverse effect on the coupling of selenoxides than on that of selenides.
The Reaction of Thio-substituted Cyclopropenium Ions with Sulfonium Methylide
Authors: Inoue Shinichi , Hori Takuya 
Published: July 2006

Abstract
The reaction between thio-substituted cyclopropenium ions and sulfonium methylides gives unanticipated ketene derivatives. This reaction is supposed to proceed through an intermediate sulfonium salt formed from ylide addition to the cyclopropenyl ring.
The Structure of the Cyclodextrin Complex. XVI. Crystal Structure of Heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin-p-Iodophenol (1 : 1) Complex Tetrahydrate
Authors: Harata Kazuaki , Uekama Kaneto , Otagiri Masaki , Hirayama Fumitoshi 
Published: July 2006

Abstract
The crystal structure of heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin–p-iodophenol (1 : 1) tetrahydrate, C63H112O35·C6H5OI·4H2O, was determined by the X-ray method. The crystal is orthorhombic with the space group P212121, Z=4, a=14.997(2), b=21.368(2), and c=28.205(3) Å. The structure was solved by the heavy atom method combined with the rigid-body least-squares technique and refined by the block-diagonal least-squares method to the final R-value of 0.094 for 3268 reflections (sinθ⁄λ&lt;0.49). Heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin is in the shape of a truncated elliptical cone. The macrocyclic ring is remarkably distorted from a regular heptagonal structure. The iodophenyl group of the guest is inserted into the host cavity. The phenolic hydroxyl group protrudes from the cavity, forming hydrogen bonds with two water molecules. The iodine atom is located at the center of the macrocyclic ring, while the benzene ring occupies its position at the base side of the cone. The crystal is built up of columns which are formed by the stack of host molecules in a head-to-tail mode along the two-fold screw axis which is parallel to the crystallographic b axis. Four water molecules fill intermolecular spaces in the crystal.
Asymmetric Transfer Hydrogenation of Prochiral α,β-Unsaturated Acids and Their Esters by Achiral or Chiral Alcohols with Ruthenium Chiral Diphosphine Complexes
Authors: Yoshinaga Kohji , Kito Taketoshi , Ohkubo Katsutoshi 
Published: July 2006

Abstract
Asymmetric transfer hydrogenations of α,β-unsaturated acids (MeCH=C(Me)CO2H, PhCH=C(Me)CO2H, CH2=C(CH2CO2H)CO2H, and HO2CCH=C(Me)CO2H) and esters (MeCH=C(Me)CO2R; R=achiral and chiral group) by alcohols (PhCH2OH, (RS)-PhCH(Me)OH, and α-d-glucofuranose derivatives) were carried out with RuCl2(PPh3)3 or Ru2Cl4((+) or (−)-diop)3 (diop=2,3-O-isopropylidene-1,4-bis(diphenylphosphino)-2,3-butanediol) at 160–190 °C. The optical purity (3.4–16.4%) of hydrogenated acids obtained with PhCH2OH and Ru2Cl4((−)-diop)3 is in the order MeCH=C(Me)CO2H&gt;PhCH=C(Me)CO2H&gt;CH2=C(CH2CO2H)CO2H&gt;HO2CCH=C(Me)CO2H, suggesting that the substrates possessing two carboxyl groups would provide an asymmetrically unfavorable coordination to the Ru(II) complex for this asymmetric reaction. In the transfer hydrogenation of MeCH=C(Me)CO2R by PhCH2OH or (RS)-PhCH(Me)OH at 190 °C, the extent of asymmetric induction of Ru2Cl4((−)-diop)3 (1.7–11.4% e.e. with PhCH2OH and 7.4–18.2% e.e. with (RS)-PhCH(Me)OH) decreases with increase in bulkiness of groups R (R=H, Me, Et, n-Bu, and PhCH2) and is not enhanced by the introduction of any groups R with chiral carbon atoms into esters (maximum 15.4% e.e.). The structural change of hydrogen donors from PhCH2OH to (RS)-PhCH(Me)OH appreciably increases the optical purity of the saturated acids and esters, and the chiral α-d-glucofuranose derivatives afford optically active saturated products, even with achiral RuCl2(PPh3)3. Features of the present reaction are discussed in relation to the reaction mechanism.
Electrochemical Additions of the Allyl and the Benzyl Groups of Allyl and Benzyl Halides to Acetone
Authors: Satoh Shohei , Suginome Hiroshi , Tokuda Masao 
Published: July 2006

Abstract
Electrolysis of allyl chloride and five molar excess of acetone in hexamethylphosphoric triamide containing 0.5 M tetrabutylammonium perchlorate gave an addition product, 2-methyl-4-penten-2-ol, in a 53% yield. Allyl groups of 1-chloro-2-methyl-2-propene, 1-chloro-2-butene(3), 3-chloro-1-butene(4), 1-chloro-3-methyl-2-butene(5), and 3-chloro-3-methyl-1-butene(6), and benzyl groups of benzyl chloride, benzyl bromide, and 1-chloro-1-phenylethane can similarly be added to acetone by electrolysis to give the corresponding alcohols in fair to good yields. Among these electrochemical reactions, those of 3, 4, 5, and 6 with acetone give respectively two isomeric homoallyl alcohols, one of the isomers is not accessible by the usual chemical reaction between allylic organometallics and acetone.
Reaction of Malonaldehyde with Nucleic Acid. I. Formation of Fluorescent Pyrimido[1,2-a]purin-10(3H)-one Nucleosides
Authors: Seto Hiroshi , Okuda Taisuke , Takesue Tomoyuki , Ikemura Tadashi 
Published: July 2006

Abstract
The reactions of malonaldehyde with guanosine and 2′-deoxyguanosine proceed slowly under acidic conditions to give new pyrimidopurine nucleosides, 3a and 3b, respectively. These compounds emit strong yellow fluorescence and are hydrolyzed by NaOH into malonaldehyde and guanosine from 3a (2′-deoxyguanosine from 3b). From chemical and spectroscopic evidence, these compounds were deduced to be 3-β-d-ribofuranosylpyrimido[1,2-a]purin-10(3H)-one (3a) and 3-(2-deoxy-β-d-erythro-pentofuranosyl)pyrimido[1,2-a]purin-10(3H)-one (3b). No products were detected in the reaction mixture of malonaldehyde with 1-methylguanosine, adenosine, cytidine, uridine, thymidine, 2′-deoxyadenosine, or 2′-deoxycytidine.
Theoretical Study of Proton and Solvent Effects on Molecular Stacking
Authors: Zuccarello Felice , Raudino Antonio , Buemi Giuseppe , Rigano Carmelo 
Published: July 2006

Abstract
Molecular stacking between π-electron systems was analyzed in connection with effects of external charge and solvent. A perturbation approach was used for calculating intermolecular energies and a discrete plus continuum model was used for solvent effects. The solvent favors stacking in unprotonated systems by hydrophobic forces. In the presence of an external charge the solvent induces dissociative effects on the molecular pairs by electrostatic solvation forces.
Furan Derivatives. V. The Syntheses of 4,5-Dihydro-3H-naphtho[1,8-bc]furans Using Strong Bases
Authors: Horaguchi Takaaki , Narita Hidetaka , Suzuki Tsuneo 
Published: July 2006

Abstract
The reaction of ethyl (4-methoxy-8-oxo-5,6,7,8-tetrahydro-1-naphthyloxy)acetate and potassium hydroxide gave a mixture of 6-methoxy-4,5-dihydro-3H-naphtho[1,8-bc]furan and 6-methoxy-4,5-dihydro-3H-naphtho[1,8-bc]furan-2-carboxylic acid in total yield above 90%. The mechanisms of formation of two products were examined, and potassium 2a-hydroxy-6-methoxy-2a,3,4,5-tetrahydro-2H-naphtho[1,8-bc]furan-2-carboxylate was isolated as a precursor of 6-methoxy-4,5-dihydro-3H-naphtho[1,8-bc]furan. It has become apparent that strong bases such as sodium hydroxide, sodium ethoxide, and sodium hydride were also useful for syntheses of 6-methoxy-4,5-dihydro-3H-naphtho[1,8-bc]furan derivatives.
Solvent Effects on the Nonradiative Relaxation Processes of the Lowest Excited Singlet States of Meso-substituted Bromoanthracenes
Authors: Hamanoue Kumao , Hidaka Toshiharu , Nakayama Toshihiro , Teranishi Hiroshi , Sumitani Minoru , Yoshihara Keitaro 
Published: July 2006

Abstract
From the measurements of the fluorescence lifetimes and the 0-1 emission maxima in solutions, it is concluded that the solvent dependence of the nonradiative transition rates of the lowest excited singlet states of 9-bromoanthracene and 9,10-dibromoanthracene is due to the different extent to which the lowest excited singlet and adjacent higher excited triplet states are stabilized by solvents.
Stereochemistry of Nucleophilic Substitution of Menthyl Derivatives with Anion of Diphenylphosphine Oxide by an Action of Sodium Dihydridobis(2-methoxyethanolato)aluminate
Authors: Yamashita Mitsuji , Soeda Yukio , Suzuki Nobuyoshi , Yamada Manabu , Tsunekawa Kenji , Oshikawa Tatsuo , Inokawa Saburo 
Published: July 2006

Abstract
The reaction of an anion of diphenylphosphine oxide prepared by the action of sodium dihydridobis(2-methoxyethanolato)aluminate on the oxide with various menthyl or neomenthyl halides and sulfonates were studied to clarify the sterochemistry of the substitution. The reaction gave neomenthyl- and methyl-diphenylphosphine oxide in ratios from 100 : 0 to 0 : 100.
A Localized Molecular Orbital Approach to the Bond Moment Theory
Authors: Shinoda Hiroyuki , Miyazaki Tomoo 
Published: July 2006

Abstract
The bond moment theory was reinvestigated by use of localized molecular orbitals derived from INDO canonical orbitals. Bond moments were defined in terms of localized molecular orbital and, together with their derivatives with respect to a C–H stretching motion, were evaluated for some simple molecules; the bond moments of acetylene and hydrogen cyanide in the C–H bending geometry were also calculated. It is concluded that the first-order approximation for the bond moment theory is inadequate to interpret infrared absorption intensity. In the C–H stretching vibration the change in trans-sited bond moment is considerably large.
The Preparation and Photoreation of Spiro[oxirane-2,6′-tricyclo[3.2.1.02,7]oct[3]en]-8′-ones. An Intramolecular Cycloaddition of Photochemically Generated Ketene with the Epoxide Ring
Authors: Nitta Makoto , Omata Akihiko , Nakatani Hazime 
Published: July 2006

Abstract
The oxidations of 1,5-dimethyl- and 1,3,5-trimethyl-6-methylenetricyclo[3.2.1.02,7]oct-3-en-8-ones with 3-chloroperbenzoic acid or thallium(III) acetate resulted in the formation of 1′,5′-dimethyl and 1′,3′,5′-trimethylspiro[oxirane-2,6′-tricyclo[3.2.1.02,7]oct[3]en]-8′-ones (2a and 2b). The oxidation occured stereoselectively on the exocyclic double bond from the exo-side. The photochemical reactions of 2a and 2b resulted in the formation of 4,8-dimethyl- and 4,6,8-trimethyl-3,4-dihydro-1H-2-benzopyran-3-ones, both of which would be derived from an ene-type reaction of the ketene intermediate with the exoxide ring involved in the [4π+2σ] electronic system. The intermediacy of the ketene was assessed by low-temperature infrared spectroscopy as well as by a trapping experiment, the mechanistic pathways were confirmed by conducting the photoreaction in deuterated methanol.
Revision of Structures of Nellionol and Dehydronellionol
Authors: Matsumoto Takashi , Imai Sachihiko , Takeda Shoji , Mitsuki Masanori 
Published: July 2006

Abstract
The structures of nellionol and dehydronellionol were revised respectively to 6α,11,12,16-tetrahydroxyabieta-8,11,13-trien-7-one (12) and 6,11,12,16-tetrahydroxyabieta-5,8,11,13-tetraen-7-one (13) by the following syntheses. A mixture of (15R)- and (15S)-12-methoxyabieta-8,11,13-trien-16-ol, prepared from 13-acetyl-12-methoxypodocarpa-8,11,13-triene, was converted into 11,12,16-triacetoxyabieta-8,11,13-trien-7-one (22) via 16-acetoxy-12-benzoyloxyabieta-8,11,13-trien-11-ol. Treatment of 22 with isopropenyl acetate, followed by oxidation with m-chloroperbenzoic acid and subsequent acetylation, afforded 6α, 11,12,16-tetraacetoxyabieta-8,11,13-trien-7-one, which was hydrolyzed with dilute hydrochloric acid to 12. The ketone 22 was also converted into 13 via 11,12,16-triacetoxyabieta-8,11,13-trien-6-one. The spectral data of 12 and 13 were in good agreement with those of natural nellionol and dehydronellionol.
Synthesis of [0]Orthocyclo[2]orthocyclo[0](1,1′)ferrocenophane and [0]Paracyclo[0](1,1′)ferrocenophane
Authors: Shimizu Iwao , Umezawa Hiroshi , Kanno Toshihiro , Izumi Taeko , Kasahara Akira 
Published: July 2006

Abstract
syn- and anti-[0]Orthocyclo[2]orthocyclo[0](1,1′)ferrocenophan-7-enes were synthesized via an intramolecular reductive coupling of 1,1′-bis(o-formylphenyl)ferrocene with low valent titanium reagents, syn- and anti-[0]Orthocyclo[2]orthocyclo[0](1,1′)ferrocenophanes and [0]paracyclo[2]paracyclo[0](1,1′)ferrocenophane were prepared by the reaction of 1,1′-bis[o-(bromomethyl)phenyl]ferrocene and 1,1′-bis[p-(bromomethyl)phenyl]ferrocene with butyllithium. The transannular π-electronic interactions between two aromatic rings in these compounds were examined on the basis of the NMR and electronic spectra.
Photochemical Activation of Zinc-Carbon and Zinc-Sulfur Bonds in Zinc Porphyrins
Authors: Nukui Masahiro , Inoue Shohei , Ohkatsu Yasukazu 
Published: July 2006

Abstract
Ethyl(N-methyltetraphenylporphinato)zinc (NMTPPZnEt 2) reacts with thiol (RSH: R=Prn, But, Ph) and hydrogen sulfide (H2S) to form N-methyltetraphenylporphinatozinc sulfide (NMTPPZnSR: R=Prn, But, Ph, H). Irradiation with visible light enhances the reactivity of 2 in the reaction with ButSH and brings about the homolytic cleavage of the zinc-sulfur bond of NMTPPZnSPrn in dichloromethane.
Restricted Rotation Involving the Tetrahedral Carbon. IL. Singly peri-Substituted 9-Isopropyltriptycenes Revisited
Authors: Yamamoto Gaku , Oki Michinori 
Published: July 2006

Abstract
9-Isopropyltriptycene derivatives carrying a fluoro, chloro, bromo, or t-butyl substituent in a peri-position were synthesized and their dynamic NMR behavior was studied to see the dependence of the barrier to rotation of the bridgehead substituent upon the bulkiness of the peri-substituent. The data obtained in this work together with those reported earlier disclose that, among the derivatives in which the peri-substituent is not buttressed by the 2-substituent, the peri-methoxy compound has the highest barrier and the barrier decreases as the bulkiness of the peri-substituent increases. 1,2,3,4-Tetrachloro and tetrabromo derivatives show the slightly positive buttressing effect.
Electrochemical Kinetic Parameters of Geometric Isomers of Singly Charged Cobalt(III) Complexes
Authors: Yamada Akifumi , Yoshikuni Tadatsugu 
Published: July 2006

Abstract
The kinetic parameters of electrode reactions of several geometric isomers of singly charged cobalt(III) complexes have been determined by means of Tast polarography. The complexes studied are trans-[Co(NCS)(NO2)(en)2]Cl·H2O, cis-[Co(NCS)(NO2)(en)2]Cl·2H2O, trans-[Co(NO2)2(en)2]NO3, cis-[Co(NO2)2(en)2]NO3, trans-[Co(NO2)2(NH3)4]NO3·0.5H2O, cis-[Co(NO2)2(NH3)4]NO3, trans-[CoCl(NO2)(en)2]NO3, and cis-[CoCl(NO2)(en)2]NO3. These complexes showed two irreversible reduction waves; the first corresponds to CoIII→CoII, and the second, to CoII→Co0. The electrochemical kinetic parameters for the one-electron reduction wave were obtained in 0.1 and 1.0 M acetate buffer solutions. The half-wave potentials for the first wave of the complexes were more positive for the cis isomers than for the corresponding trans isomers. The cathodic rate constants at E=0 for the cis isomers were also larger than those for the corresponding trans isomers. A slight increase in the rate constant with the decrease in ionic strength was observed.
Thermal Properties and Raman Spectra of Crystalline and Vitreous BaZrF6, PbZrF6, and SrZrF6
Authors: Kawamoto Yoji , Sakaguchi Fumiko 
Published: July 2006

Abstract
Differential thermal analysis and Raman spectroscopic studies have been performed of crystalline and vitreous BaZrF6, PbZrF6, and SrZrF6 compounds in order to examine the thermal properties and the F coordination of Zr. The differential thermal analyses clarified the definite phase transformation characteristics of crystalline BaZrF6, and SrZrF6 and also suggested that the low- and high-temperature modifications are present in PbZrF6 as well as in BaZrF6 and SrZrF6. The Raman spectra of crystalline BaZrF6, PbZrF6, and SrZrF6 were discussed in relation to the F coordination of Zr in fluorozirconate compounds. The crystallization behaviors and Raman spectra of vitreous BaZrF6, PbZrF6 and SrZrF6 revealed that Zr in the vitreous compounds is eight-coordinated by F although small amounts of seven-coordinated Zr may exist in vitreous BaZrF6.
Metal Complexes in Organic Synthesis. VIII. Allylic Alcohols as Starting Materials in Palladium-catalyzed Wittig-type Olefinizations
Authors: Moreno-Mañas Marcial , Trius Antonio 
Published: July 2006

Abstract
Allylic alcohols, aldehydes, and triphenylphosphine participate in a one-pot process catalyzed by palladium, which is formally equivalent to the Wittig olefinization. It can be applied to both aliphatic and aromatic aldehydes. The resulting olefins which appear as mixtures of stereoisomers were fully hydrogenated. Two different mechanisms can account for the observed results.