The asymmetric autocatalysis is an enantioselective synthesis where the asymmetric catalyst and the product possess the same structure and the same absolute configuration. We disclosed chiral α-isopropyl-3-pyridinemethanols, α-isopropyl-5-pyrimidinemethanols, and α-isopropyl-3-quinolinemethanols operate as asymmetric autocatalysts in the enantioselective additions of i-Pr₂Zn to 3-pyridinecarbaldehyde, 5-pyrimidinecarbaldehyde and 3-quinolinecarbaldehyde, respectively. Especially, practically perfect asymmetric autocatalysis ( >99% yield and >99.5%e.e.) is attained by using 2-(3,3-dimethyl-1-butynyl)-α-isopropyl-5-pyrimidinemethanol as an asymmetric autocatalyst. Moreover, consecutive asymmetric autocatalytic reaction enables α-isopropyl-5-pyrimidine- and α-isopropyl-3-quinolinemethanols as well as 5-(1-hydroxy-2-methylpropyl)pyridine-3-carboxamides with extremely low e.e. to automultiply with dramatic amplification of e.e. without any assistance of other chiral auxiliaries.
It was also found that various chiral compounds can operate as chiral initiators in the enantioselective addition of i-Pr₂Zn to 5-pyrimidinecarbaldehydes and α-isopropyl-5-pyrimidinemethanols with high e.e. were obtained. For example, in the presence of L-leucine with 2%e.e., asymmetric autocatalysis affords an (R)-α-isopropyl-5-pyrimidinemethanol with high e.e. It is known that asymmetric degradation of racemic leucine using circularly polarized light (CPL) gives chiral leucine (ca. 2%e.e.). Thus, asymmetric autocatalysis with amplification of e.e. serves as a correlation between CPL and highly enantiomerically enriched organic molecules. Moreover, enantiomorphic inorganic crystals such as quartz (SiO₂) and sodium chlorate (NaClO₃) can be utilized as chiral initiators and an α-isopropyl-5-pyrimidinemethanols with high e.e. was obtained in high yields.

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The reaction of 1-buten-3-yne with acetic acid was examined in the presence of transition metal catalysts. Among catalysts examined, Pd(OAc)₂ or H₂[PtCl₆] was an effective catalyst forconverting 1-buten-3-yne to the corresponding acetic acid adducts and corresponding dimerization product. With these catalysts a mixture of 1-acetoxy-1,3-butadiene and 2-acetoxy-1,3-butadiene was obtained along with the dimerization product (1,3,7-octatriene-5-yne). Under Pd(OAc)₂ catalyst, the dimerization product was produced almost exclusively. The mechanism for the formation of this head-to-head dimerization product is discussed.

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Reaction processes and effect of the structures, basicities, and reaction conditions in the reaction of amines with isocyanato(trimethyl)silane and triethoxy(isocyanato)silane which are noted to be pseudohalosilanes and also heterocumulenes were investigated. It was revealed that the amines as a nucleophile competitively attack the silicon and the isocyanato group to form the substitution products of silylamine together with urea derivative and the addition product of silylurea in appreciable yields according to the preference of reactions depending on the structure and basicity. In the reaction with triethoxy(isocyanato)silane, furthermore, the addition reaction took place more easily and selectively compared with that of isocyanato(trimethyl)silane.

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Structure and mechanical properties of the mixtures of asphalt and the triblock copolymer poly[styrene-block-(ethylene-co-propylene)-block-styrene](SEPS) were studied by differential scanning calorimetry (DSC), needle penetration and softening point, and tensile strength measurements. From the measurements of glass transition temperature in the mixture of asphalt components and SEPS, maltene, the soluble fraction extracted from the asphalt in heptane, was partially miscible with the ethylene/propylene block of SEPS, whereas asphaltene, the insoluble fraction in heptane, partially miscible with the polystyrene block. The mixture of asphalt and SEPS was a partially miscible system. The viscosity, needle penetration and tensile strength of the mixtures may be improved in the low concentration of SEPS (e.g. 5–10 wt%). A microstructure model of SEPS-asphalt blend system with the lower amount of SEPS was proposed and efficaciously approached to explain the resulting phenomena. The small amount of SEPS in asphalt seem to act as a compatibilizer and emulsify the two components of asphalt to make a mechanically stable network.

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A periodic change in the thickness of a crosslinked poly(4-vinyl-N-methylpyridinium chloride) gel membrane, induced by a periodic voltage change, could be performed for several hours on a microelectrode. The amplitude of the change of thickness was proportional to the applied voltage, and is dependent on the degree of crosslinking and the concentration of NaCl solutions, in which all the membranes were preliminarily equilibrated before use. Moreover, a propagating wave could be generated on the surface of the gel membranes by using a 5-electrode.

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Bis(sulfophenyl) phosphonate-formaldehyde resin was prepared by the reaction of diphenyl phosphonate-formaldehyde resin with fuming sulfuric acid. This resin was used as an acid catalyst for esterification of malonic acid, succinic acid, gultaric acid and adipic acid with ethanol by bath and column method. In bath method the yields of the esters were about 83.0% at 100 °C for 1 h. In column method the yields of the esters were 59.0–63.0% at 100 °C with the developing speed (24 cm³/h).

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Alumina-modified titania sample (Al–TiO₂) in anatase form was synthesized by thermal decomposition of mixtures of alkoxides of titanium and aluminum in toluene at 300 °C. The Al–TiO₂ prepared from titanium(IV) isopropoxide (TIP) and aluminum ethoxide (Ti/Al mole ratio 9) transformed into rutile at around 1000 °C, and it possessed a surface area of 48 m² g⁻¹, even after calcination at 800 °C for 1 h. Another Al–TiO₂ prepared from TIP and aluminum isopropoxide showed lesser thermal stability (39 m² g⁻¹ at 800 °C), suggesting that reactivity of aluminum alkoxides determines the thermal stability of produced Al–TiO₂.

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