bluuebunny/crossref_metadata_2025_split huggingface dataset:
Four Different Coordination Modes of 1,1′-Bis(diphenylphosphino)ferrocene: Synthesis, X-Ray Crystal Structure, and Iron-57 Mössbauer Spectroscopy of Four Metal Carbonyl Complexes with 1,1′-Bis(diphenylphosphino)ferrocene (dppfe)
Authors: Onaka Satoru , Moriya Takeshi , Takagi Shigeru , Mizuno Atushi , Furuta Hiroyuki 
Published: July 2006

Abstract
Four kinds of methal carbonyl complexes with 1,1′-bis(diphenylphosphino)ferrocene (dppfe) are synthesized and their molecular structures are determined by single-crystal X-ray analyses. Crystal data for (η5-CH3C5H4)Mn(CO)2dppfe (1), (η5-CH3C5H4)Mn(CO)dppfe (2), [ClMn(CO)4]2(μ-dppfe) (3), and CH3CCo3(CO)7dppfe (4) are as follows: 1, Pbca, a = 20.551(3), b = 28.951(5), c = 11.786(1) Å, V = 7012(2) Å3, Z = 8; 2, P21/n, a = 18.682(5), b = 20.495(4), c = 9.750(2) Å, β = 91.24(2)°, V = 3732(1) Å3, Z = 4; 3, A2/a(C2/c), a = 18.978(5), b = 15.293(4), c = 16.513(5) Å, β = 112.62(2)°, V = 4423.9(2) Å3, Z = 4; 4, , a = 13.031(2), b = 15.338(2), c = 11.583(2) Å, α = 99.13(2)°, β = 98.35(2)°, γ = 99.64(2)°, V = 2218.1(7) Å3, Z = 2; Mo Kα radiation; R = 0.075, 0.084, 0.074, and 0.056 for 2639, 4219, 2575, and 6098 reflections, respectively. Dppfe functions as a monodentate ligand in 1 with the rotational angle 128.0° for two cyclopentadienyl rings, as a bidentate chelating ligand in 2 with the rotational angles 3.1°, as a bidentate bridging ligand (no metal–metal bond) in 3 with the rotational angle 180°, and as a bridging ligand (over metal-metal bond) in 4 with the rotational angle 69.6°, respectively; Mn–P = 2.242(4) Å (1), Mn–P = 2.215(2) and 2.216(3) Å (2), Mn–P = 2.364(4) Å (3), and Co–P = 2.297(2) and 2.314(2) Å (4). The two cyclopentadienyl rings of dppfe are slightly tilted (2.3–5.7° for tilt angles in 1, 2, and 4) and are parallel in 3. The coordinated P atoms are significantly displaced from the cyclopentadienyl ring planes. From the comparison of these geometrical parameters, it is concluded that the rotation of the two cyclopentadienyl rings is a predominant factor to determine various coordination modes of dppfe rather than the tilt of the two rings and/or the deviation of the P atoms from the ring plane. The 57Fe Mössbauer spectra of this series of compounds show doublets with parameters (IS = 0.50–0.52 mm s−1 relative to Fe, QS = 2.22–2.35 mm s−1). Although isomer shifts are essentially constant, the quadrupole splittings have a tendency to increase with the increase of the rotational angle of the two cyclopentadienyl rings. 1H and 31P NMR spectra are measured for all of these compounds.
Diastereoisomers of Platinum(II) Complexes with Chiral N-Substituted 1,2-Diamines. I. Structure and Isomerization of Dichloro{(R)-2-[(2-methyl-2-aminopropyl)amino]-1-butanol}platinum(II)
Authors: Saito Reiko , Goto Masafumi , Hirose Junzo , Kidani Yoshinori 
Published: July 2006

Abstract
Square-planar complexes with the formula [PtCl2(R-Hb-Mepn)], where R-Hb-Mepn is (R)-2-[(2-methyl-2-aminopropyl)amino]-1-butanol CH3CH2CH(CH2OH)NHCH2C(CH3)2NH2, were synthesized and separated into two diastereoisomers. On the basis of CD spectroscopic and X-ray crystallographic analyses, (+)300- and (−)300-isomers were determined to have the R-nitrogen center with λ chelate ring and the S-nitrogen center with δ chelate ring, respectively. R(N)-[PtCl2(R-Hb-Mepn)] crystallizes in the monoclinic space group P21 with a = 8.809 (1), b = 8.9960 (4), c = 8.536 (1) Å, β = 108.787 (5)°, Z = 2, R = 0.042, and RW = 0.062. S(N)-[PtCl2(R-Hb-Mepn)] crystallizes in the orthorhombic space group P212121 with a = 9.287 (1), b = 14.831 (1), c = 9.141 (1) Å, Z = 4, R = 0.029, and RW = 0.034. 1H NMR spectra indicate that R-Hb-Mepn chelate rings take fixed conformation in acidic D2O solution. At high temeprature (90–95 °C), the conversion of the R(N)-isomer to the S(N)-isomer occurred easily. The R(N)-[PtCl2(R-Hb-Mepn)] and S(N)-[PtCl2(R-Hb-Mepn)], respectively, show the opposite Cotton effect to that of the reported complexes R(N)-[PtCl2(S-Me-pn)] and S(N)-[PtCl2(S-Me-pn)] (S-Me-pn = (S)-1-methylamino-2-aminopropane). The kinetic data of a reversible inversion reaction at the nitrogen were consistent with the usual base catalyzed mechanism.
Equilibrium and EXAFS Studies of Mercury(II) Porphyrin in Aqueous Solution
Authors: Tabata Masaaki , Ozutsumi Kazuhiko 
Published: July 2006

Abstract
Formation of the 2 : 1 mercury(II) porphyrin complex, Hg2(tpps)2− (H2tpps4−: tetrakis(4-sulfonatophenyl)porphyrin), in aqueous solution has been investigated. Equilibrium studies revealed that main chemical species is Hg2(tpps)2− even in a solution of a 1 : 1 molar ratio of Ctpps/CHg and the Hg2(tpps)2− complex is very stable thermodynamically. EXAFS (extended X-ray absorption fine structure) analysis of the Hg2(tpps)2− complex in aqueous solution showed that the Hg–N bond length within the complex is 215(2) pm and the bond length is much shorter than the Hg–O bond length (240 pm) within the hydrated mercury(II) ion. Thus the very strong Hg–N bond is formed upon the complexation of Hg2(tpps)2− and the strong bond formation supports the high stability of the Hg2(tpps)2− complex. Deformation of Hg2(tpps)2− is also discussed in connection with catalytic effect of mercury(II) on metalloporphyrin formation.
X-Ray Diffraction Studies on the Structure of the Tri- and Tetrathiocyanatomanganate(II) Complexes and Solvated Lithium Ion in N,N-Dimethylformamide
Authors: Radnai Tamás , Ishiguro Shin-ichi , Ohtaki Hitoshi 
Published: July 2006

Abstract
The structure of the tri- and tetrathiocyanato-N-manganate(II) complexes in N,N-dimethylformamide (DMF) solution was determined by the solution X-ray diffraction method at 25 °C. The most probable structure of the tri-complex is octahedral with additional three DMF molecules in the first coordination sphere, while the tetra-complex is tetrahedral. The Mn–O and Mn–N bond lengths were determined to be 220 pm in both complexes. The structure of the octahedrally solvated lithium ion [Li(dmf)6]+ with the Li–O bond length of 195 ppm was also determined in an LiSCN solution of DMF.
Growth Process of ZSM-5 Zeolite Film
Authors: Sano Tsuneji , Mizukami Fujio , Takaya Haruo , Mouri Takashi , Watanabe Masami 
Published: July 2006

Abstract
The growth process of a ZSM-5 zeolite film was studied using EDX-SEM, TEM, and EDX-STEM. It became clear that the ZSM-5 zeolite film was formed through a successive accumulation of zeolite crystals of 5 to 10 μm size. It was also found that the crystalline embryos with high Al concentration existed in the vicinity of the inner side of the zeolite film and within the film.
Qualitative Triplet Potential Energy Curves of Arylethylenes along the Double Bond Twisting
Authors: Kikuchi Osamu , Segawa Katsunori , Takahashi Ohgi , Arai Tatsuo , Tokumaru Katsumi 
Published: July 2006

Abstract
The potential energy curves of triplet states of styrene, 2-vinylnaphthalene and 2-vinylanthracene were calculated by the restricted open-shell SCF MNDO methods as a function of the twist angle of the external double bond. It was shown that the shape of the lowest triplet potential energy curve is determined by the relative energies of two triplet states, the “ring-excitation” and “olefin-excitation” states.
1,3-Bis(salicylideneamino)-2-propanol as the Ligand for Manganese(III) Ions
Authors: Mikuriya Masahiro , Yamato Yo , Tokii Tadashi 
Published: July 2006

Abstract
Reaction of 1,3-bis(salicylideneamino)-2-propanol (H3L) with manganese(II) acetate tetrahydrate in the presence of ethylenediamine and sodium thiocyanate give a salen complex [Mn(salen)(NCS)] (H2salen = N,N′-disalicylideneethylenediamine), while that in the presence of water and triethylamine gives a binulear manganese(III) complex [Mn2(L)2(H2O)]·3CH3OH. Both complexes have been characterized by X-ray crystal structure analyses, electronic spectra, and magnetic susceptibilities.
Decomposition of [2.2.2]Cyclophane-1,2-dione Mono- and Bis(tosylhydrazone)s
Authors: Hatta Taizo , Mataka Shuntaro , Tanimoto Satoshi , Tashiro Masashi , Tsuge Otohiko 
Published: July 2006

Abstract
Monotosylhydrazone (2) of [2.2.2]cyclophane-1,2-dione (1) decomposed on silica gel, giving the ring-contracted [2.2.1]cyclophane-17-carboxylic acid (4). The electronic spectrum of 4 showed a red shift of the λmax and a broadening of the peak shape in comparison with that of di-p-tolylacetic acid, due to a through-space π–π interaction. Thermolysis of bis(tosylhydrazone) (3) afforded [2.2.2] cyclophan-1-en-1-yl p-toluenesulfonate (6). An intermediate formation of the corresponding[2.2.2]cyclophan-1-yne is suggested.
Ring-Splitting Reaction of 2,2-Diarylthietane by Electron-Transfer Photosensitization of 9,10-Dicyanoanthracene
Authors: Shima Kensuke , Sazaki Akira , Nakabayashi Kenichi , Yasuda Masahide 
Published: July 2006

Abstract
A 9,10-dicyanoanthracene (DCA)-photosensitized reaction of 3-cyano- or 3-ethoxy-2,2-diarylthietane in acetonitrile gave selectively 2-cyano- or 2-ethoxy-1,1-diarylethene. The ring-splitting reaction proceeds via a one-electron oxidation of the sulfur atom of thietane ring by a photochemical electron transfer to the excited singlet state of DCA.
Crystal Structures of TXC8-TTF (X = Se,Te)
Authors: Nakano Chikako , Wang Ping , Imaeda Kenichi , Maruyama Yusei , Inokuchi Hiroo , Yamochi Hideki , Saito Gunzi 
Published: July 2006

Abstract
The crystal structures of TSeC8–TTF and TTeC8–TTF were determined by X-ray analysis. The molecules in both compounds have chair-like forms and take columnar structures. The distance between the least-squares planes of the central skeleton along the stacking axis in the TSeC8–TTF crystal is nearly equal to that of the TTeC8–TTF crystal. This result is consistent with the fact that the electrical resistivities for both single crystals are of the same order.
Vapor-Phase Beckmann Rearrangement of Cyclohexanone Oxime over an HY Zeolite Catalyst Calcined at High Temperature
Authors: Sato Satoshi , Takematsu Kiyotaka , Sodesawa Toshiaki , Nozaki Fumio 
Published: July 2006

Abstract
The vapor-phase Beckmann rearrangement of cyclohexanone oxime over an HY zeolite calcined at high temperatures was investigated. Cyclohexanone oxime was rearranged into ε-caprolactam with high conversion at 573 K over an HY zeolite calcined at 873 K. The activity decay was slight, while oxime conversion over an HY zeolite calcined at 773 K steeply decreased during the initial stage of the reaction. The catalytic activity for the rearrangement was not correlated with the physical properties of a fresh catalyst, but with those of a used one, especially regarding their porosity and acidity. It was also found that the produced ε-caprolactam was tightly adsorbed on strong aicd sites, filling the micropores of the zeolite during the initial stages of the reaction, and that a large portion of the catalytic reaction proceeded mainly on weak acid sites located in a region near to the external surface of the zeolite.
The Catalytic Electroreduction of Dioxygen on Iron Protoporphyrin IX Modified Glassy Carbon Electrodes
Authors: Arifuku Fumihiro , Mori Keiko , Muratani Tomomi , Kurihara Hirondo 
Published: July 2006

Abstract
The catalytic electroreduction of dioxygen at iron(III) protoporphyrin IX (hemin) modified glassy carbon electrodes was investigated in an aqueous solution within the pH range 1–13. The reduction potential of dioxygen on a hemin chemically modified electrode was more anodic than that on a hemin adsorbed electrode by a few tens of mV. The results of rotating disk and ring-disk voltammetric measurements indicated that the oxygen molecule is reduced via a one-step reduction accompanying four-electron and four-proton transfer at pH &lt; 11, and via two successive reductions accompanying two-electron transfer and, subsequently, two-electron and four-proton transfer at pH &gt; 12. The quantity of peroxide formation at hemin-adsorbed electrodes decreased with increasing pH, up to 10, and then increased with increasing pH beyond 12. The possible overall mechanisms for the catalytic reduction of dioxygen are described.
The Solvent Extraction and Dissociation of the Ion Pair of Alkali Metal Complex of Monodisperse Poly(oxyethylene) Derivatives with Picrate Ion
Authors: Kikuchi Yoichi , Nojima Yasuhiko , Kita Hiroyuki , Suzuki Toshio , Sawada Kiyoshi 
Published: July 2006

Abstract
The ion pair extraction of the alkali metal ion complex of poly(oxyethylene) monododecyl ethers (DEOn: n = 4, 6, and 8, where n refers to the number of the oxyethylene unit) with picrate ion into 1,2-dichloroethane (1,2-DCE) has been studied by means of a vapor pressure osmometry and a solvent extraction. The extraction equilibria have been interpreted by taking into consideration the ion pair dissociation in 1,2-DCE. Thermodynamic constants of the extraction and the dissociation of the ion pairs have been evaluated from a quantitative analysis of the extraction data. The extractability of the alkali metal ion increases in the order Li+ &lt; Na+ &lt; Cs+ &lt; K+, irrespective of the number of oxyethylene (EO) unit of DEOn. This order was interpreted by the formation constant of the DEOn–alkali metal ion complex in the aqueous phase. The formation constants of the DEOn–alkali metal ion complex both in the aqueous phase and in 1,2-DCE increase with the increase in the number of EO unit. The interionic distance between the cationic complex and picrate ion of the ion pair was estimated from the dissociation constant in 1,2-DCE.
Synthesis of Alkyl Substituted p-Benzoquinones from the Corresponding Phenols Using Molecular Oxygen Catalyzed by Copper(II) Chloride–Amine Hydrochloride Systems
Authors: Shimizu Masao , Watanabe Yoshihito , Orita Hideo , Hayakawa Takashi , Takehira Katsuomi 
Published: July 2006

Abstract
2,4,6-Trimethylphenol was effectively oxidized to trimethyl-p-benzoquinone with molecular oxygen in the presence of a catalytic amount of copper(II) chloride–amines in alcohol at ambient temperature. Various amines could be used as a co-catalyst in the presence of acids, and especially hydroxylamine hydrochloride and acetone oxime coupled with hydrochloric acid showed high activity. 2,6-Dimethyl-p-benzoquinone was also obtained from 2,6-dimethylphenol in good yield in this catalytic oxidation system.
Synthesis of a Polycyclic π-Conjugated System Containing an Azulene Unit by the Flash Vacuum Pyrolytic Method. I. Synthesis and Properties of Cyclopent[a]azulenes
Authors: Kitamori Yoichiro , Yasunami Masafumi , Hioki Takanori , Kikuchi Ikue , Takase Kahei 
Published: July 2006

Abstract
1H- and 3H-cyclopent[a]azulene were synthesized in excellent yields by applying flash vacuum pyrolysis. Their structures were clearly determined. A mixture of 1H- and 3H-cyclopent[a]azulene was completely anionized with methyllithium in THF, but 67% so in ether. Although 1H-cyclopent[a]azulene reacted with dichloroketene to give a [2+2] cycloadduct, 3H-cyclopent[a]azulene reacted with cyclopentadiene to give a [4+2] cycloadduct. These chemical behaviors were predictable according to HMO theory.
Synthesis and Properties of Pheophorbide-Quinone Compounds
Authors: Borovkov Victor V , Gribkov Alexander A , Kozyrev Andrei N , Brandis Alexander S , Ishida Akito , Sakata Yoshiteru 
Published: July 2006

Abstract
New pheophorbide-quinone derivatives with a different kind of quinone moieties were synthesized by mixed anhydride method. The structures of these compounds were confirmed by UV, IR, 1H NMR, fluorescence, and mass spectra. Effective fluorescence quenching of the pheophorbide chromophores in the synthesized molecules was observed depending on the electron-accepting properties of the quinone fragment and spatial disposition of the donor and acceptor. Electron-transfer rate constants were calculated based on fluorescence decay measurements. The role of energetic and conformational changes of pheophorbide-quinones in the electron-transfer processes is discussed.
Synthesis and Some Reactions of Ethyl 2-[2-(Substituted Methyleneamino)anilino]cyclohepta[b]pyrrole-3-carboxylates
Authors: Abe Noritaka , Kakehi Akikazu 
Published: July 2006

Abstract
We synthesized Schiff bases, ethyl 2-[2-(benzilideneamino)anilino]cyclohepta[b]pyrrole-3-carboxylate (2a) and ethyl 2-[2-(2-butenylideneamino)anilino]cyclohepta[b]pyrrole-3-carboxylate (2b), from ethyl 2-(2-aminoanilino)cyclohepta[b]pyrrole-3-carboxylate (1) in excellent yields by treating 1 with benzaldehyde or 2-butenal in the presence of molecular sieves 4A, respectively. Further, the cyclization and cycloaddition reactions of the Schiff bases were investigated. Treatment of 2a with iron(III) chloride or Pd–C gave ethyl 2-(2-phenylbenzimidazol-1-yl)cyclohepta[b]pyrrole-3-carboxylate and 12H-5,13-dihydrocyclohepta[1′,2′ : 4,5]pyrrolo[2,3-b][1,5]benzodiazepin-12-one (4). A similar treatment of 2b, however, gave ethyl 2-(4-methylqinolin-8-yl)aminocyclohepta[b]pyrrole-3-carboxylate and 4. The reaction of 2a with dimethyl acetylenedicarboxylate (DMAD) gave 15a-ethyl 5,6,7,15-tetramethyl 15,15a-dihydro-14H-pyrrolo[2′,1′ : 1,2]isoquino[3,4-b][1,5]benzodiazepine-5,6,7,15,15a-pentacarboxylate (6) and methyl 4-(3-ethoxycarbonylcyclohepta[b]pyrrol-2-yl)-3-oxo-1,2,3,4-tetrahydroquinoxalin-2-ylideneacetate (7). The reaction of 2b with DMAD, however, gave the 1,4-dihydropyridine derivative as a Diels–Alder adduct, along with 7. The structures of 6 and 7 were confirmed by single-crystal X-ray analyses.
Reaction of Tantalum–Alkyne Complexes with Isocyanates or Acyl Cyanides. Stereoselective Functionalization of Carbon–Carbon Triple Bonds
Authors: Kataoka Yasutaka , Oguchi Yoshiyuki , Yoshizumi Kazuyuki , Miwatashi Seiji , Takai Kazuhiko , Utimoto Kiitiro 
Published: July 2006

Abstract
Treatment of alkynes with low-valent tantalum derived from TiCl5 and zinc produces tantalum-alkyne complexes (not isolated), which react in situ with phenyl isocyanate (or butyl isocyanate) to give (E)-α,β-unsaturated amides stereoselectively. The tantalum–alkyne complexes also react with acyl cyanides in the presence of BF3·OEt2 to give α-cyanohydrins. In both reactions, filtration of the reaction mixture containing the tantalum–alkyne complexes before addition of isocyanates (or acyl cyanides) is indispensable to obtain good yields.
The Selective Separation of Organic Acids through Liquid Membrane Containing Ferrite in the Presence of Alternating Magnetic Field
Authors: Sakai Yasuzo , Konno Emi , Tsuchida Satoru , Takahashi Fujio 
Published: July 2006

Abstract
The selective separation of phenylglyoxylic acid (PGA) from a mixture of PGA and mandelic acid (MA) was carried out by using a liquid membrane containing ferromagnetic powder (LM-FP) in the presence of an alternating magnetic field (A-MF). Ferromagnetic powder, which exhibits a strong coercive property, was added into a mixture of toluene and chloroform (T–C mixture). Many holes of 0.7 mm in diameter were bored in the bottom wall of a Teflon® cylindrical bottle, in which the total hole area occupied 8%. A T–C mixture containing ferromagnetic powder was filled into the holes to prepare LM-FP. Under an exposure of A-MF (200 Oe, 50 Hz) over a 12 h. Fifty four % PGA and 8% MA in the source phase were found to permeate through the LM-FP-containing Sr-ferrite from the source phase of an equimolar mixture of PGA and MA to the receiving phase. The PGA permeation rate through the LM-FP varied over a region between 0.3 and 7.5 times higher than that through a control liquid membrane not containing any ferromagnetic powder in the presence of a magnetic field.
Electron Transport and Redox Chain Reactions in a Mosaic Membrane
Authors: Igawa Manabu , Takabayashi Yasuhiko , Koizumi Toshiaki 
Published: July 2006

Abstract
A circulating current enhances transports of ions and electrons in a mosaic membrane system with ion-exchange membranes and electron-transport membranes. Electron transport is readily coupled to ion transport in a new mosaic membrane with electron-transport regions and ion-exchange regions. Electrons and ions are transported in the same or opposite direction by the driving forces of the redox potential gradient or the concentration gradient. Redox chain reactions are also generated in the mosaic membrane system as the electron flow in biological membranes.
Thermodynamic and NMR Studies on the Complexation of Lanthanoid(III) Ions with o-Phenylenediamine-N,N,N′,N′-tetraacetate in Aqueous Solutions
Authors: Yamamoto Mineko , Nakasuka Noriyuki , Tanaka Motoharu 
Published: July 2006

Abstract
The complex formation of o-phenylenediamine-N,N,N′,N′-tetraacetate (PhDTA, H4L) with trivalent lanthanoid ions (M3+) in aqueous solutions has been studied at a temperature of 25.0 ± 0.2 °C and an ionic strength of 1.0 M in NaClO4 by potentiometry, calorimetry, and 1H and 139La NMR. The formation constant, KML, of 1 : 1 PhDTA complexes increases monotonically with the atomic number of the central metal ions (log KML = 11.39 for La, and 16.26 for Lu), showing the tetrad effect and a linear free energy relationship with the formation constant of CyDTA complexes. The change in entropy increases gradually with increasing atomic number, as is the case for EDTA. The large change in entropy ( ≈ 257–329 J K−1 mol−1) overweighs the endothermicity ( = 5.4–14.6 kJ mol−1) of the complexation. The NMR study indicated that the La–PhDTA complex has four acetate groups with an identical magnetic environment and a lanthanum nucleus with higher electric symmetry in comparison with the corresponding EDTA and CyDTA complexes.
Preparation and Characterization of [Co(tp)2(Men-en)]+ (tp = Tropolonate Ion; Men-en (n = 1−4) = N-Methyl Substituted Ethylenediamine), Inversion and Deuteration at Chiral Nitrogen Centers of [Co(tp)2(Me-en or Me3-en)]+, and Crystal Structures of [Co(tp)2(N,N-Me2-en)]ClO4 and Λ(R)Δ(S)-[Co(tp)2(Me-en)]ClO4
Authors: Kojima Masaaki , Ma Guilin , Miyamoto Toshiro , Ohba Shigeru , Fujita Junnosuke 
Published: July 2006

Abstract
A series of complexes of the type [Co(tp)2(R1R2NCH2CH2NR3R4)]+ (tp = tropolonate ion; R1–R4 = H or CH3) were prepared and characterized by physicochemical methods. The rates of OH−-catalyzed deuteration (H → D, kD) and inversion (epimerization, kep) at the chiral amine nitrogen centers of [Co(tp)2(Me-en or Me3-en)]+ (Me-en = N-methylethylenediamine, Me3-en = N,N,N′-trimethylethylenediamine) in aqueous solutions were measured at 34.0 °C. The kD and kep values are, respectively, ca. 10 and ca. 103 times as large as those of [Co(acac)2(Me-en or Me3-en)]+ (acac = 2,4-pentanedionate ion). The reduction (Co3+/Co2+) half-wave potential increases from −0.31 (vs. SCE) for [Co(tp)2(en)]+ (en = ethylenediamine) to −0.09 V for [Co(tp)2(Me4-en)]+ (Me4-en = N,N,N′,N′-tetramethylethylenediamine) in spite of the expected electron-donating effect of the methyl groups, and the results were ascribed to the steric effect of –N(CH3)2. This interpretation was supported by the X-ray analysis of [Co(tp)2(N,N-Me2-en)]ClO4 (N,N-Me2-en = N,N-dimethylethylenediamine) in which the Co–N(tertiary amine) bond length (2.022(4) Å) is longer than the Co–N(primary amine) one (1.930(3) Å). The crystal data and R value are: Monoclinic, C2/c, a = 16.558(3), b = 13.541(2), c = 19.125(3) Å, β = 102.62(1)°, V = 4184(1) Å3, Z = 8, R = 0.044 for 2009 observed unique reflections. The crystal structure of Λ(R)Δ(S)-[Co(tp)2(Me-en)]ClO4 was also determined. The crystal data and R value are: Monoclinic, P21/a, a = 11.608(5), b = 22.754(9), c = 7.936(6) Å, β = 106.02(7)°, V = 2015(2) Å3, Z = 4, R = 0.084 for 1057 reflections.
Slab Optical Waveguide with Octadecylsilane Coated Surface for Absorption Detector of Flow Analysis
Authors: Tsunoda Kin-ichi , Itabashi Hiromitsu , Akaiwa Hideo 
Published: July 2006

Abstract
A K+ doped glass slab optical waveguide (SOWG) was coated with octadecylsilane (ODS) to separate and concentrate analytes onto the SOWG with hydrophobic interaction between analytes and ODS. As an absorption detector of flow analysis, the ODS–SOWG detector was almost insensitive to a blue dye (bromothymol blue) which is not adsorbed to the surface of the SOWG. On the other hand, it was highly sensitive to another blue dye of coomassie brilliant blue G-25O (CBB) which is firmly adsorbed onto the SOWG surface.