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s The reductive amination of acetophenone, (+)-camphor, and 5α-cholestan-3-one over Ru and Pd metals as well as their carbon-supported catalysts gave corresponding amines together with alcohols as by-products. However, we found that the corresponding amines are selectively synthesized by the addition of ammonium chloride to the reaction system with depression of the formation of alcohol, as exemplified with acetophenone. Although alcohols are usually not formed over Pd with alicyclic ketones, the alcohols formation was effectively depressed over Ru in the presence of ammonium chloride. The effects of the additive on the stereoselectivity of the formation of amines are also discussed in the cases of (+)-camphor and 5α-cholestan-3-one.

The thermal decomposition of phthalate alone and with poly(vinyl chloride) (PVC) was carried out under a nitrogen atmosphere in a 4-necked separable flask. The thermal decomposition of phthalate in the presence of PVC began at 150°, about 100°C lower than the decomposition of phthalate alone. The formation of octyl chloride indicated an interaction reaction between phthalate and PVC. From the analysis of the composition of commercially plasticized PVC sheet (film and board), the phthalates (dibutyl phthalate, dihexyl phthalate) and di(2-ethylhexyl) phthalate), 2-ethyl-1-hexanol, phthalic anhydride, and 2-ethylhexyl hydrogen phthalate were identified. The mutagenicities of these decomposition products were higher than those of phthalic diesters (phthalates).

Pd metal catalysts were prepared by the reaction of palladium(II) chloride with sodium aluminate at pH 6—10. The Pd catalysts prepared at pH 10 contained only small amounts of Al (0.14 wt%), were the most thermally stable, and kept large specific surface areas and high catalytic activities in the hydrogenation of nitrobenzene even after hydrogen treatment at high temperatures up to 380 °C.

8族金属触媒によるノナナールの還元アミノ化を行い,第一級アミンのノニルアミン(1),第二級アミンのジノニルアミソ(2)および第三級アミンのトリノニルアミン(3)の生成に対する触媒の選択性を検討した.1の生成率はPd < Os < Pt < Rh < Ir < Raney Ni(R-Ni)=Ru < RaneyCo(R-Co)の順で,R-Coで94%,R-NiとRu触媒で87%と1が高収率で生成した.PdとOs触媒上では1よりも2が多く得られ,2の収率はそれぞれ62%と53%で,特にPd触媒上では1の生成は24%にすぎなかった.3はPd触媒(6%)やOs触媒(1%)上でのみわずかに生成した.NH4C1を添加しても1の生成は増加しなかったがパラジウム黒触媒上ではNH4Clの添加により3の生成が6%から45%に増加した.反臨中に中間体として生成するシッフ塩基(5)の最大生成量はR-Niで69%,R-Coで67%,Ru触媒で53%といずれもこれらの触媒上で最終的に生成する2の量よりはるかに多く,これらの触媒上では5にアンモニアが付加してイミン(4)と1に分解する経路が存在することが判明した.また3の前駆体(8)が中間体として生成することが認められた.8に関しても5と同様の分解経路が存在することが判明した.触媒による1および2への選択性の相違を5のエナミンへの異性化を含む反応経路を考慮して考察した.

Partial hydrogenation of the exo-olefinic bond in limonene to carvomenthene proceeds smoothly by photocatalytic hydrogen transfer from 2-propanol using [Rh6(CO)16] as a catalyst under UV-irradiation in the presence of acetone. Hydrogen gas evolves after the formation of carvomenthene has been completed. 1-Hydroxy-1-methylethyl radical formed in the reaction of photochemically excited acetone with 2-propanol serves both as an activator for the catalyst and as a hydrogen source.

Thermal diffusion columns, consisting of water-cooled glass tubes and a coaxial red-hot metal wire, were applied as the reactor to dehydrogenative coupling of ethylene or C4 hydrocarbons. This application was intended to separate hydrogen spontaneously from other products, especially from aromatics, leading to enhanced yields. Hydrogen gas would ascend the red-hot wire, while the aromatics would descend the cold glass walls. When the metal wire was actually red-hot in the reactant hydrocarbon flow, oily products were really formed, most of which were mono- and bicyclic aromatic compounds such as benzene, styrene, and naphthalene. Product distributions were measured for different reactant species, wire metals, wire temperatures, and a few additional variables. Especially notable was the selective formation of 4-vinyl-1-cyclohexene from 1,3-butadiene at relatively low temperatures near 600 °C.

A facile and efficient synthesis of the carboxyl-linked glucosides of bile acids is described. Direct esterification of unprotected bile acids with 2,3,4,6-tetra-O-benzyl-D-glucopyranose in pyridine in the presence of 2-chloro-1,3,5-trinitrobenzene as a coupling agent afforded a mixture of the alpha- and beta-anomers (ca. 1:3) of the 1-O-acyl-D-glucoside benzyl ethers of bile acids, which was separated effectively on a C18 reversed-phase chromatography column (isolated yields of alpha- and beta-anomers are 4-9% and 12-19%, respectively). Subsequent hydrogenolysis of the alpha- and beta-acyl glucoside benzyl ethers on a 10% Pd-C catalyst in acetic acid/methanol/EtOAc (1:2:2, by vol) at 35 degrees C under atmospheric pressure gave the corresponding free esters in good yields (79-89%). Chemical specificities such as facile hydrolysis and transesterification of the acyl glucosides in various solvents were also discussed.

Partial hydrogenation of the exo-olefinic bond in limonene to carvomenthene proceeds smoothly by photocatalytic hydrogen transfer from 2-propanol using [Rh6(CO)16] as a catalyst under UV-irradiation in the presence of acetone. Hydrogen gas evolves after the formation of carvomenthene has been completed. 1-Hydroxy-1-methylethyl radical formed in the reaction of photochemically excited acetone with 2-propanol serves both as an activator for the catalyst and as a hydrogen source.

The homogeneous and heterogeneous hydrogenations of methyl 4-t-butyl -1-cyclohexenyl ether (I), methyl 4-t-butyl-1-cyclohexenyl ester (II) and methyl 4-t-butyl-1-methylcyclohexene (III) over Rh and Pd metals and the Rh metal complex catalyst, RhCl(PPh3)3, are reported. The isomer distributions of products formed from I, II and III are compared for the homogeneous and heterogeneous catalytic hydrogenations. The hydrogenations of I, II and III over Rh metal catalyst give mainly the cis isomer for I and II, whereas the trans isomer is formed in large excess over the Rh metal complex. The implications of these stereochemical results for the mechanism are examined on the basis of the exchange patterns obtained during the deuteration of the substrates, as well as on the basis of various kinetic factors. In addition, the effects of the solvent and the ligands of the Rh complex catalyst on the stereochemistry of hydrogenating II have been investigated. The trans isomer is obtained in 93% yield when o-cresol is used as the solvent. The Rh complex containing the dimethylaminophenylphosphine ligand gives the largest amounts of trans isomer (93%).

Heat-condensation reaction of Phthalic Anhydride (1a) with Phthalide (2a) or the corresponding sulfur compounds (1b), (2b) were investigated.The products were not only Biphthalide type compounds (3), but also much a condensed cyclic type isomer (4).The yield and ratio of products were remarkably changed by the combination of sample and reacted condition.

Heat-condensation reaction of Phthalic Anhydride (1a) with Phthalide (2a) or the corresponding sulfur compounds (1b), (2b) were investigated.The products were not only Biphthalide type compounds (3), but also much a condensed cyclic type isomer (4).The yield and ratio of products were remarkably changed by the combination of sample and reacted condition.