The organometallic system consisting of alkyllithium and amine as an initiator for the polymerization of 1, 3-cyclohexadiene (CHD) was studied. As a specific system consisting of butyllithium (n-BuLi)and N, N, ' N, '-tetramethy1-1, 2-ethanediamine (TMEDA) was found to be particularly active as an initiator of living anionic polymerization of CHD. Poly (1, 3-cyclohexadiene) (PCHD) yielded had high molecular weight with narrow molecular weight dispersity. PCHD had two kind of microstructure in the main chain (1, 2-unit and 1, 4-unit), the molar ratio of which was determined by measuring 2D-NMR. The glass transition temperature of PCHD was found to rise with an increase in the ratio of 1, 2-unit to 1, 4-unit. Hydrogenated poly (1, 3-cyclohexadiene), as it was called, polycyclohexene showed higher heat resistance and modulus than those of PCHD. The designs of poly (1, 3-cyclohexadiene-blockbutadieneblock-1, 3-cyclohexadiene), P (CHD-block-Bd-block-CHD), triblock copolymers and the effects of microphase structures on the mechanical and thermal properties of several triblock copolymers were also reported. Heat resistance of the completely hydrogenated triblock copolymers was found to be higher than that of the unhydrogenated triblock copolymers, nevertheless lower mechanical strength than those of the unhydrogenated triblock copolymers with the same weight ratio of CHD to butadiene. To clarify the relationship between the higher order structures of those triblock copolymers and their properties, the degree of compatibility between the polycyclohexene (PCHE)block sequence and the poly (ethylene/butylene) (PEB) block sequence was observed and it found to be increased. The micro phase separation structure of those triblock copolymers was considered to become minute by hydrogenation of P (CHD-block-Bd-block-CHD).

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A new type of crown compounds were efficiently prepared by means of intramolecular [2 + 2] photocycloaddition of styrene derivatives, which were named “crownophanes” due to possessing both crown ether and cyclophane moieties. It was found that prototypical crownophane showed relatively high Li⁺ ion selectivity on the solid-liquid extraction. Simple and appropriate modification of the crown compounds was performed, taking the complexation with Li⁺ ion into consideration. Crownophanes bearing two cyclobutane rings (crownopaddlanes) extracted the ion exclusively and quantitatively. A double-looped crownophane with two crown ether moieties selectively transported size-complementary dibasic acids in the liquid membrane system. Heterocrownophanes, which have sulfur or nitrogen atoms in and on the crown ether ring systems, were also prepared by this method and found to extract Ag⁺ ion with high selectivity and efficiency, and among others the crownophane possessing py ridine rings on the aromatic nuclei recorded the perfect selectivity on the liquid-liquid extraction.
At the preparation of a tertiary amine-containing crownophane (cryptocrown ophane), the photochemical cyclization was successfully carried out in the presence of γ-CD.

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Stabilities of steady states in a reaction model for generation of enantiomers were studied and conditions for spontaneous appearance of an optically acitive state were clarified. In this reaction system, an excess of either D-or L-enantiomer is realized as a result of competition between two stereoselective, autocatalytic reactions of the respective enantiomers and is determined by chance.

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Lithium-doped indium oxide crystals (In₂O₃: Li_x, x=0-1.0) were synthesized by calcination in flowing oxygen of dried powders from aqueous solutions of InCl₃ with Li. Only the peaks from cubic In₂O₃crystal were observed in X-ray diffraction (XD). The lattice constant increased from 10.116 to 10.163Å, and the optical absorption energy decreased from 2.72 to 2.68 eV with increasing x in In₂O₃: Li, . The lattice constant estimated by XD and the optical absorption edge in UV-visible absorption spectrometry remained at constants (10.163 Å and 2.68 eV) in the region of x=0.5-1.0. Tight-binding (TB)band-structure calculations were performed for studying changes in the electronic structure with Li doping. The calculated energy splitting between the top of the valence band and the bottom of the conduction band decreased by Li doping at the empty sites (8a and 16c) of pure In₂O₃ crystal, which was consistent with the experimental decrements of the absorption energy with x in In₂O₃: Lix. Changes in the valence band spectra by X-ray photoelectron spectroscopy of the In₂O₃: Lix (x=0, 0.2 and 1.0)agree with that in the density of states by the TB calculation for two Li atoms doped at 8a or at 16c sites of In₂O₃ crystal. Doping of Li atoms into the interstitial sites affects both on the valence band and the conduction band minimum of the In₂O₃ crystal.

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The reaction of triisocyanato (methyl) silane with ammonia in diethyl ether, tetrahydrofuran or pyridine was investigated. Isocyanato (methyl) silazane was isolated as a white powder soluble in organic solvents after removal of the oligomers by means of reprecipitation. The isolated polysilazane was unstable and easily polymerizable and was composed of the unit structures of MeSi (NH)_X/2(NCO)_3-X( X =1, 2, 3)with a number average molecular weight of 500. However, the reaction of methylisocyanatopolysilazane with amine provided silylurea derivatives of polysilazane with a softening point, spinnability, and stability against condensation.

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Photochemical formation and scavenging of hydroxyl radical (OH radical) was investigated using rain (n=69) and dew (n=26) waters collected during June, 1997 to June, 1998 in Higashi-Hiroshima city, Hiroshima prefecture. For the sources of OH, it was found that majority of OH radical was formed from sources other than nitric acid or nitrous acid photolysis in rain waters. For dew waters, almost all o(f the OH radical was formed from nitrite ion (NO2^-) photolysis. Scavenging rate constants (Σ (k_{scavenger, OH}[scavenger])) for rain waters ranged from (0.2-1.6)×10⁵s^-1and the mean was 0.7×10⁵s^-1. For dew waters, scavenging rate constants ranged from (2.1-4.6)×10⁵ s^-1 and the mean w as 3.4×10⁵ s^-1. The corresponding lifetimes of OH radical for rain and dew waters were estimated to be on the average 20.6 and 3.2 ps, respectively. For rain waters, it was speculated that majority of the OH radical was scavenged by dissolved organic compounds. On the other hand, nitrous acid scavenged on the average 59% of OH radical in the dew waters studied here. Based on the aqueous-phase photochemical sources of OH in rain and dew waters and scavenging rate constants, steady-state OH radical concen-t rations were estimated to be approximately 1×10^-15 M(1M =1mol dm^-3) for both rain and dew waters.

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A preparation method for high performance porous titanium trichloride catalyst for propylene polymerization was established. α-Titanium trichloride was selectively obtained by reducing titanium tetrachloride with a concentrated alkylaluminum compound. Highly active porous titanium tri chloride catalyst was obtained from the mixture of dibutyl ether (ether/Ti>1.0) and hexachloroethane (C₂Cl₆/Ti>0.8). This catalyst showed 15% higher activity than conventional porous titanium trich loride catalyst. In the treatment of the mixture, crystalline structure would be transformed from α-form to δ-form by the action of chlorine radical. It is considered that the stabilityand the amount of chlorine radical are important to obtain high activity catalyst.

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The porous lithium aluminates were developed as a catalyst support for vapor phase synthesis of dimethyl carbonate. The porous lithium aluminates were prepared by the impregnation of activated alumina with Li salt and the subsequent thermal treatment at 800°C. The crystal structures of the materials were identified as the inverse spinel structure in which Li⁺ and part of Al³⁺ ions located in the sites octahedrally coordinated with oxide ions and other Al³⁺ ions located in the sites tetrahedrally coordinated with oxide ions. The Pd-Cu-Cl catalysts supported on these porous lithium aluminates were employed for the vapor phase dimethyl carbonate synthesis from methyl nitrite and carbon monoxide. These catalysts showed higher activities and selectivities for dimethyl carbonate formation than that supported on activated alumina. According to the measurements of physical properties of the catalyst carriers, the lithium aluminates had micropores of scores to hundreds angstrom of diameter and comparatively weak surface acidic sites as well as basic sites. The high catalytic performances of lithium aluminates supported Pd-Cu-Cl catalysts result from not only the acid-base properties but also these moderate porosity of the the lithium aluminates carriers.

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5-Aminolevulinic acid (ALA) is known as a selective and biodegradable herbicide which is also recognized as the growth promotive factor at low concentration. The authors studied on the synthesis of ALA from 1, 5-dihydroxy-2-pyridone (DHPy) via piperidine-2, 5-dione (PDO). DHPy can be obtained easily from 2-furaldehyde by the conventional method. PDO was synthesized from DHPy by the reductive dehydroxylation with 5% Pd-C catalyst in an ethanol solution under a hydrogen atmosphere for 24hours refluxing. However, yield of PDO was 14% and that of 5-hydroxy-2-pyridone (HPy) was 28%. Considering the deactivation of the catalyst by the basic products, dil. HCl or acetic acid was added into the ethanol solution. As the result, dil. HCl addition reduced PDO yield, while acetic acid addition enhanced PDO yield. Furthermore, PDO yield was increased to 65 % and HPy yield was 21% when the reaction was carried out at room temperature in an acetic acid solution. HPy, by-product of this reaction, could be converted to PDO in 75% yield by the reduction with Pd-C in a methanol solution at room temperature. Therefore, the total yield of PDO was about 80%. PDO was hydrolyzed with dil. HCl and the final product of ALA HCl was obtained in 60% yield.

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Protonation of the metal diphenylphosphide formed by the reaction of chlorodiphenylphosphine with a representative metal such as magnesium, aluminium, zinc, or tin at room temperature gave diphenylphosphine in satisfactory yields. Especially activated zinc in THF was found to be the most effective system than other combinations. Transition metals also reacted with chlorodiphenylphosphine but were inferior to the representative metals except for the case of manganese as the reductant. Dialkylphosphines such as dicyclohexylphosphine and di-t-butylphosphine were also produced under the similar conditions from the corresponding chlorophosphines in 67% and 31% yields, respectively.

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