The kinetics of liquid-phase hydrogenation of benzonitrile in the presence of a reduced nickel catalyst were studied at temperatures ranging from 70 to 100°C. The initial concentrations of benzonitrile in 250 ml methanol varied from 25 to 50g.Under given conditions, the absorption rate of hydrogen was first order in catalyst concentration. It was independent of the partial pressure of hydrogen and of the concentration of benzonitrile over a relatively low conversion range. The activation energy was calculated to be 8.8 Kcal/mol.The reactions to form Schiff-bases and secondary amines became evident when the absorption rate of hydrogen was low. Such reactions were markedly accelerated when the hydrogenation reaction was interrupted.Hydrogenation of benzonitrile was also studied in the presence of n-butylamine. The results indicated that when the absorption rate of hydrogen was high, the amine was involved in the formation of Schiff-bases as well as secondary amines only to a very slight extent. Upon interruption of the hydrogenation reaction, however, the presence of amine gave rise to the formation of mixed Schiff-bases.

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The kinetics of liquid-phase hydrogenation of isophthalonitrile in methanol-ammonia (1:1) in the presence of a reduced nickel catalyst and a Raney nickel catalyst were studied at temperatures ranging from 90 to 110°C.In the presence of a reduced nickel catalyst, the reactions proceeded in a stepwise manner, m-cyanobenzylamine being the intermediate. Under given conditions, the absorption rate of hydrogen was first order in catalyst concentration and agreed with the Langmuir-type rate equation for the partial pressure of hydrogen. At a partial pressure of hydrogen above 70 kg/cm², the absorption rate was not affected by the partial pressure. The effects of isophthalonitrile concentration also agreed with the Langmuir-type rate equations. The adsorption of isophthalonitrile and m-cyanobenzylamine was relatively strong and their adsorption equilibrium constants almost comparable with each other. The specific rate constant for isophthalonitrile was almost three times as much as that for m-cyanobenzylamine. The activation energy for the reaction was calculated to be 12.8 kcal/mol.Similar reaction mechanisms can also be applied for the hydrogenation in the presence of a Raney nickel catalyst.

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Reactions between alkali phenoxides and carbon dioxide in nitrobenzene have been studied under various conditions.When potassium phenoxide was treated with carbon dioxide in nitrobenzene, salicylic acid was obtained in a good yield, whereas the formation of p-hydroxybenzoic acid was depressed as compared with similar reactions conducted in N, N-dimethylformamide. From sodiun phenoxide and carbon dioxide, salicylic acid was obtained as a main product, but p-hydroxybenzoic acid undetectable.Similar reaction was also carried out in nitrobenzene containing N, N-dimethylformamide. Though the yield of p-hydroxybenzoic acid was improved, the total yield of hydroxybenzoic acids was decreased.

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Anemonin (1) was synthesized by photochemical dimerization of protoanemonin (2). Thus, a methanol solution of (2) was irradiated at -50°C under a 250 W high pressure mercury lamp to obtain a crystalline dimer (1), mp 153°C, and polymers.Catalytic hydrogenation of (1) yielded tetrahydroanemonin, which, with subsequent oxidation with potassium permanganate, gave dilevulinic acid, mp 158°C. Tetrahydroanemonin was reduced with lithium aluminium hydride to obtain a tetraol derivative (8), which showed no signal in its n.m.r. spectrum less than 4τ and was not oxidized with lead tetraacetate. The configuration of (1) has thus been established to be (9).

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