2-Ethenyl-8-quinolinols containing bulky substituents in the 2-position of the ethenyl group have been prepared. From the NMR and X-ray analysis data, O, N and 2-C atoms of the ligand are expected to be in-plane of the tridentate. Cyclometalation of the ligands with Na₂[PdCl₄] in the presence of pyridine in MeOH took place at 25°C to give (ca.60%) the neutral chelate complex possessing a Pd (II)-C σ bond. When the pyridine was exchanged with triphenylphosphine, steric interactions arose throu gh three substituents bonded to α-C, β-C of chelate ring and PPh₃. As revealed from X-ray analysis bis (benzyl ester) groups in Pd complex, the mutual repulsion by adjacent groups causes the dis tinction between disubstituents. The resolution of the diastereomer was thus accomplished by the column chromatography. These indicate that Pd-C bond in cyclometalate ring is stable even under the inherent structural molecular strain.

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The thermal and photochemical oxidations of 1-benzyl- or 1-alkyl-1, 4-dihydronicotinamides (BNAH, RNAHs, respectively) were kinetically examined in the presence of unmodified cyclodextrins (CyDs) or modified CyDs with one or two 3-chloro-1, 4-dioxo-2-naphthylamino groups (hereafter, naphthoquinone moiety: Q) on the primary or secondary side (QCyDs). The α- and β-CyDs formed an inert binary host-guest complex with either of a BNAH or the CyD-free naphthoquinone (NQ), but yCyD afforded a ternary complex exhibiting a weak reactivity only in lower concentrations of γ-CyD than BNAH. The reactivity of QCyDs toward BNAH (k_obs/10^-4 s^-1) decreased in the order: 6-QβCyD (4.1)>3-QβCyD (3.5)>6-QβCyD (2.5)>6-QγCyD (2.2)>3-QαCyD (1.9) at [BNAH]/[QCyDs] 1. The sequence was independent of the nature of the 1-alkyl substituents. Meanwhile, 1-ethyl-1, 4-dihydronicotinamide with a benzyl group at the 3-carbamoyl nitrogen (EBNAH) showed a different rate sequence: 6-QβCyD (3.9)>6-QγCyD (2.7)> 6-QβCyD (2.3)>3-QβCyD (1.7)>3-QαCyD (1.1). Thus, the RNAH (BNAH) and EBNAH molecules seem most suitable for the β-CyD and γ-CyD cavities, respectively.

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The three kinds of TEMPO radical derivatives (TEMPO (-H), TEMPOL (-OH), TEMPOAM (-NH₂) ) having different substituents in the molecule as the spin probe agents were added to the poly(vinyl chloride) (PVC) including dioctyl phthalate (DOP) as plasticizer, and the rotational correlation times τ_c^(m) of the radical derivatives were obtained in the temperature range of 90-180°C by the ESR measurement. The values of τ_c^(m) for each radical decreased by increasing the quantity of DOP added to PVC. Similarly, the values of τ_c^(m) decreased by increasing the temperature. The decrease of τ_c^(m) may be explained by the decrease of the density of the PVC resin and, thus, the decrease of the viscosity of PVC resin, due to the addition of DOP and the increase of the temperature. It has been cleared that the value of τ_c^(m) varies depending on the kinds of functional groups (-H, -OH, -NH₂) in TEMPO radical derivatives, indicating the existence of the interaction between the PVC molecule and the functional groups (-H, -OH, -NH₂) in TEMPO derivatives. The energies of the above interactions were calculated with the UHF-PM3 method by using the MOPAC 93 program. TEMPO derivativesand DOP increases in the order of TEMPO<TEMPOL =DOP<TEMPOAM. Low stabilization energy was obtained for the TEMPO derivatives, which show fast rotation motion in PVC resin.

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Relative magnitude of the orientational order of liquid crystal (LC) molecules at the (polymer/LC) interface against that in the bulk phase was evaluated by two different methods. One was an indirect method based on the statistic phenomenological theory by measuring the difference between the nematicisotropic phase transition temperatures (T_NI) at the interface and that in the bulk phase. The other was a rather direct method based on the optical second-harmonic generation (SHG) technique that could evaluate the orientational order of the LC molecules contacting with the substrate surface. Qualitative agreement was obtained for the results of interfacial order of the LC molecules from these two methods. The orientational order of LC molecules at the (polymer/LC) interface was strongly dependent upon the difference of interfacial energy between the polymer and LC molecules.

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Industrially available aromatic polyesters of bisphenol A polyarylate is conventionally produced by the interfacial condensation polymerization of bisphenol A and the mixture of terephthaloyl/isophthaloyl chlorides. We now report a new synthetic method without using the acid chloride derivatives. The synthesis of oligomeric polyarylate by the melt condensation polymerization of bisphenol A and diphenyl terephthalate/isophthalate (mole ratio of reactants is 1/0.5/0.5), and the crystallization of this oligomeric polyarylate contacting with the proper solvent have been previously repoted. This crystallized oligomeric polyarylate could be polymerized by the solid-state condensation polymerization into a high molecular weight polymer with excellent color. The key point to obtain a high molecular weight polymer was to adjust precisely the mole ratio of the end-groups of -OH and phenyl. The molecular weight of the obtained polymer reached to twice that of the commercial polyarylate and the molecular weight distribution hadthe most probable distribution of Mw/Mn=2. The high molecular weight polyarylate showed an excellent wear property. The melting points of the obtained polymers were over 280°C, and some polymers showed a melting point over 300°C. These values were nearly 40°C higher than the reported value of the maximum melting point of the random copolyarylate composed of bisphenol A, terephthalic and isophthalic acid (mole ratio of bisphenol A/terephthalic/isophthalic acid =1/0.5/0.5).

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It was found that an exfoliated graphite (E. G) can sorb very quickly a large amount of heavy oil. The maximum sorption capacity on E. G. was found to be very high, 86 g of A-grade heavy oil per 1 g of an exfoliated graphite, which is much larger than the package of absorbents (polypropylene) have ever used. E. G have small surface area and total pore volume, a little less maximum sorption capacity (about 70 g/g) was observed.
On observat ion through SEM and porosimeter, differences of morphology on exfoliated graphite (samples A and B) were detected. The sorption capacity and rate for sorption of heavy oil into exfoliated graphite were depended on shape of exfoliated graphite (bulk density, specific surface area and total pore volume).

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5-Aminolevulinic Acid (ALA) is known as a selective herbicide and one of the agricultural chemicals which promote the growth of plants. The authors studied on the practical synthesis of ALA from Nacetylfurfurylamine (AcFA). AcFA was converted to 2-acetamidomethy1-2, 5-dimethoxy-2, 5-dihydrofuran by electrolytic or bromine-methanol oxidation. It was changed to the tetrahydro compound by catalytic reduction with Raney Ni under ordinary temperature and pressure. The tetrahydro compound was oxidized to N-acetyl-ALA with potassium permanganate in a diluted sulfuric acid solution. N-Acetyl-ALA gave ALA hydrochloride by the hydrolysis with diluted hydrochloric acid. Overall yield of ALA hydrochroride was about 42%.

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The conductivity of several alkali metal thiocyanates in water-methanol mixtures was measured at 25°C. The data were analyzed using the Lee-Wheaton theory for symmetrical electrolytes to obtain ion association constant, K_A, limiting molar conductivity, Δ₀, and limiting ionic molar conductivity, λ₀^±. In all the solvent systems, calculated λ₀⁺ values of the alkali metal ions increase in the order Li⁺<Na⁺<K⁺<Rb⁺<Cs⁺. The.λ₀^± values of the alkali metal ions and thiocyanate ion showed a minimum whe n the molar fraction of methanol was ca.0.4. The changes in λ₀^± of these alkali metal ions and thiocyanate ion with the molar fraction of methanol agree with the change in the viscosity of the solvent or the heat of mixing of water-methanol mixtures. These alkali metal thiocyanates form little or no ion aggregated in water and water-methanol mixtures. These alkali metal thiocyanates were K_A=15-24 dm3 mol^-1 in methanol.

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Two new diterpenes 1 and 2 were isolated from the fruit of Vitex rotundifolia L. fil. These compounds were determined as abieta-9 (11), 12-diene and abietane 9 (11): 12 (13)-di-α-epoxide, respectively. Structural determination of 1 was made by the connection of spectroscopic data and the results that 1afforded known αγ-abietatriene (3) by air oxidation. That of 2 was also made by the comparison of spectroscopic data of the MCPBA oxidation products 2, 4, and 5 of 1 and by the analysis of the epoxide ring opening reaction product of 4.

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A ¹³C-NMR spin-lattice relaxation time of methanol was measured with solutions of o-, m-BDS (BDS: benzenedisulfonate) and perchlorate of some divalent transition metals in water-methanol mixture. The comparison in NMR data between water-methanol mixture and pure methanol solution gave the number of methanol molecules that locate in the first solvation sphere of divalent transition metal ions. The results show that divalent transition metal ions are preferentially hydrated in all the Mn²⁺ and Cu²⁺ salt/H₂O/Me0H systems, while in the Coo-BDS and Nio-BDS/HH₂0/MeOH system s, both Co²⁺ and Ni²⁺ show no preferential solvation behaviors, presumably due to the o-BDS^2- counter ion effect.

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