In an attempt to introduce the site (s) available for modification into the macrocyclic ring of calixarenes, cyclic phenol-formaldehyde oligomers having such a group as carbonyl, sulfur, chiral amino acid residue (Val, Trp, Cys and Cys-S-S-Cys), or thiophene ring as bridge (s) were synthesized stepwise. The oxocalix[n]-(n=4-6) and thiacalix[4]arenes (S_n, n=1-4) form crystalline inclusion cornplexes with organic solvents. NMR studies (VT-NMR, ¹H-NMR relaxation times(T₁/s), etc. ) indicated that the oxo- and thia-analogs preferentially existed in cone conformations in CDCl₃, which are much more flexible than the parent calixarenes. The greater flexibility of the oxocalixarenes is ascribable to strong intramolecular hydrogen bonding between bridging CO and the neighboring phenolic OH groups; the flexibility is in the order, oxocalix[5]>[6]>[4]. Replacement of the methylene bridge by sulfur weakened the intramolecular hydrogen bonding characteristic for calixarenes. The mean T₁ values for the aromatic protons in the molecules of the thiacalixarenes gave an excellent linear relationships with the strength of the hydrogen bonding (ν_OH, δ_OH) or with the energy barriers (Δ G†) of the conformational inversion of the diarylmethane units. The calixarene analogs incorporating the amino acid residue in the macrocyclic ring, as well as homoazacalixarenes with the chiral unit as side chain, were found to have chiral cavities. With the dihomoazacalixarenes constructed from the L-amino acid methyl esters and bischloromethylated p-cresole-formaldehyde tetramer, ¹H-NMR chemical shift non-equivalence was observed for the methyl protons of racemic trimethyl (1-phenylethyl) ammonium iodide.

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Anodic oxidation of cyclic amino acids was performed in a strong basic solution by galvanostatic and potentiostatic methods.1 mM (1 M=1 mol dm^-3) tryptophan, tyrosine, histidine and proline were completely decomposed within 100 min at a constant current of +1.15 mA cm^-2, and converted to CO₂, NH₂, HCOOH etc. Rate constants for potentiostatic oxidation of these amino acids (1.29×10^-2min^-1for tryptophan) at +1.8 V vs. Ag/AgC1 were larger than those for aliphatic amino acids (6.82×10^-3min for lysine) indicating that the adsorption of the cyclic amino acids to electrode surface promo tes their decomposition. Adsorption and decomposition processes of cyclic amino acids were studied by in situ FT-IR. In the oxidation of tyrosine, it was suggested that phenolic and carboxylic moieties start to be adsorbed on electrode at +0.3 and +0.4 V, respectively, followed by the decarboxylation at higher potential than +1.1 V.

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Methane rich city gas has been synthesized by means of steam reforming of naphtha; however, the produced gas always contains significant concentration of CO and CO₂. Therefore, development of a methane production process containing no CO and CO₂ removal processes is strongly requested.
Authors reported in the previous paper that C₃H₈→2CH₄+C(1) took place over Ni/SiO₂ with 90%selectivity. In this paper, the catalyst supports were studied and found that neutral SiO₂ and a-Al₂O₃ are suitable but the activity was much reduced over Ni supported on acidic SiO₂-Al₂O₃. Catalyst was diluted by various materials to avoid blocking-up by the deposited carbon. Several diluted materials affected the conversion. α-Al₂O₃ and basic MgO accelerated the reaction which may be due to interaction between Ni and dilution materials with direct contact. Over Ni/SiO₂, reaction (1) took place with 90%selectivity, so that the produced gas always contained H₂ formed by the C₃H₈→3C+4H₂ (2). It has confirmed that H₂ in a high concentration of CH₄ can be reacted with C₃H₈ to produce CH₄. From these results, a following simple synthesis process can be constituted; the first step is CH₄, H₂, and solid C formation from C₃H₈, and the second step is succeeding H₂ consumption process of the produced gas in the first step.

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Previously, we have reported the methodology for chemical conversion of guaiazulene (7-isopropyl1, 4-dimethylazulene, 1) to 7-isopropyl-4-methylazulene-1-carbaldehyde (4) by protecting-deprotecting technique of reactive 3-position. In the synthetic scheme, DDQ (2, 3-dichloro-5, 6-dicyano-p-benzoquinone, 5c) was used to convert unreactive 1-methyl group into formyl one. Computational calculation (RHF/ 3-21G/ /AM1) suggested that (1) o-chloranil (6b) is also effective as the oxidant instead of DDQ, which decomposes to highly toxic hydrogen cyanide (HCN), and (2) three weaker oxidants (p-benzoquinone (5a), and p-chloranil (5b), and o-benzoquinone (6a)) do not oxidize the desired reactants. In accordance with these prediction, 3-trichloroacetyl derivative (2d, Z=-COCCl₃) was successfully converted to the corresponding 1-formyl derivative (3, Z=-COCCl₃) in 90% yield, when treated with 3-equimolar o-chloranil. Moreover, the treatment of 2d with the latter three oxidants gave no 1-formyl derivative. The oxidation of 1-methyl group of azulene derivatives by quinones is considered to be thermodynamically controlled, according to the same tendency between the theoretical predictions and the experimental results.
This study provided a good example of successful prediction of experimental results by simple application of computational technique in organic synthesis.

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Poly (1, 1-difluoroethylene) (hereafter named poly (vinylidene fluoride) (PVdF)) in the mixed solvent of y-butyrolactone/cyclohexanone converts to thermally reversible gel. Gelation process of PVdF in the mixed solvent was investigated by Fourier transform infrared (FT-IR) measurement and gelation time (t_gel)was measured as a function of composition of cyclohexanone (X_cyclo) in the mixed solvent.
FT-IR spectra suggested that gelation of PVdF in γ-butyrolactone/cyclohexanone mixe d solvent occurred through crystallization of polymers taking two kinds of conformations, T₃GT₃G and TGTG. t_gel increased slowly with increasing X_cyclo, and showed maximum value at X_cyclo≅30vol%, then decreased with increasing X_cyclo According to measurement of cloud temperature of PVdF solution, the mixed solvent showed the maximum solvent power at X_cyclo≅30vol%. That is, cosolvency appeared at this composition. It is considered, therefore, that crystallization and gelation of PVdF in the mixed solvent proceed very slowly at X_cyclo≅30vol%.

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The behavior of Izod impact strength of acrylonitrile-butadiene-styrene (ABS) resins with the addition of silicone fluid has been investigated using some graft structure. Poly (dimethylsiloxane) was used as silicone fluid, and added to the resins in the range of 0 to 0.1 wt%. In the case of lower graft density, Izod impact strength was almost the same as that observed in the absence of silicone fluid, though, the effect of added silicone fluid was marked in the case of higher graft density. Therefore, it was suggested that silicone fluid exists at near the rubber phase and gives a significant effect to the initiation of craze by contributing to the entanglement of graft phase and matrix phase.

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Environmental distribution of trihalomethanes (chloroform, bromodichloromethane, dibromochloromethane, bromoform) was studied in closed coastal marine area such as Ise, Kinuura and Atsumi Bays in Aichi Prefecture, and rivers drain into each Bay from August 1996 to May 1998. In surface water samples, chloroform was found in widespread sites, at maximum concentration of 14.46 μg/L in rivers drain into Ise Bay and 1.48 μg/L in Ise Bay, respectively, except for less polluted area in offshore sea and rural inland. In marine area, higher levels of chloroform were found at heavily polluted sites. Bromoform was also determined widely around polluted coastal sites, at maximum concentration of 2.51 μg/L in Ise Bay and 0.14 μg/L in Kinuura Bay, respectively, but rarely in river sites. This indicate s bromoform is formed in polluted coastal and estuarine area.
Vertical distribution of trihalomethanes was determined in the interior of bay area. Chloroform levels were high in surface water, but bromoform levels were almost the same from surface to 6 m in depth.

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A new method of preparation of porous titanium trichloride catalyst for propylene polymerization was developed. α-Titanium trichloride was selectively obtained by the reduction of titanium tetrachloride with concentrated alkylaluminum compound. It was then, converted to porous δ-titanium trichloride catalyst by treating with the mixture of ether and chlorinated organic compounds. The aluminum cornpound contained in the α-titanium trichloride solid was extracted with ether, and simultaneously the crystalline structure of titanium trichloride was transformed from α-type to δ-type with chlorinated organic compound. The porous δ-titanium trichloride catalyst showed very high activity for propylene polymerization and gave highly isotactic polypropylene. It was proposed that chlorine radical formed by the reaction of chlorinated organic compound and extracted alkylaluminum compound transformed to crystalline structure, on the basis of the results chlorinated organic compound in which the chlorine atoms have lower negative charge gave catalysts with higher propylene polymerization activity.

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In a closed reaction vessel, chlorobenzenes were exclusively hydrodechlorinated to give benzene in the presence of zinc powder, water, sodium hydroxide, and a catalytic amount of metallic nickel in ethanol under nitrogen atmosphere. The reaction was accelerated by adding excess zinc powder, water, and stoichiometric amount of sodium hydroxide to the catalyst system. Water was a hydrogen source and sodium hydroxide was a trapping reagent of hydrochloric acid produced. A probable reaction pathway was presented.

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4-Phenylpentacyclo [5.3.0.0^{2, 5}.0^{3, 9}.0^{4, 8}]decan-6-one underwent acid-catalyzed rearrangement to give two isomeric chloro or tosyloxy derivatives having tricyclo[5.2.1.0^{4, 8}]dec-2-ene ring system, according to the type of the acid, Lewis acid containing chlorine or TsOH.

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