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Ethylene glycol was oxidized to glycolic acid in an alkaline solution over a Pt/C catalyst, and data were collected at 40°C and ambient pressure in a liquid-full reactor. During a run, strong catalyst deactivation took place, but could be partly reversed by temporarily stopping the reaction or treating the catalyst with formalin. The catalyst activity could also be restored (though not completely) by oxidizing the deactivated catalyst with oxygen, followed by reduction with hydrogen. The deactivation of the catalyst is ascribed to the formation of some oxidized species (unknown) of platinum and/or to catalyst poisoning. The reactivation of the catalyst during the stopping period or on treatment with formalin is considered to be due to a reduction reaction between the oxidized species of Pt and ethylene glycol or formalin. The decay of catalyst activity is well described by a first-order deactivation process.

Vapor-phase synthesis of benzyl cyanide from 2-phenylethanol and ammonia was studied over Ni-Cu-SiO2 catalyst in the presence of hydrogen. Experiments were carried out in a flow reactor system under atmospheric pressure at 300°. The main product was benzyl cyanide, and toluene and phenethylamine were also produced. The Ni-Cu-SiO2 catalyst (Ni/Cu=3/1) gave the best selectivity for benzyl cyanide, 80%. The deactivation of this catalyst was negligible. By kinetic analysis, the rate of loss of 2-phenylethanol was found to show a first order dependency on the partial pressure of 2-phenylethanol, and was not affected by the partial pressures of ammonia and hydrogen. The experimental data were well interpreted by a model in which phenethylimine was produced as an intermediate and was then dehydrogenated to benzyl cyanide.

The oxidation of diethanolamine to N-(2-hydroxyethyl) glycine in alkaline solution was carried out over a Pd-Al2O3 catalyst in a liquid-full reactor, and the effect of mass transfer on the global rate of reaction was studied. Data were taken at 40°C and atmospheric pressure. Experiments were first done to determine the order of reaction with respect to oxygen, which was found to be 0.64 for an assumed tortuosity factor of 3.4 for the catalyst particles. Under the reaction conditions used, the effective mass transfer area between liquid and porous catalyst was found to be less than the outer surface area of the particles. With 0.5% Pd-Al2O3 catalyst, the global rate of reaction was mainly controlled by liquidsolid and intraparticle mass transfers, and the reaction was considered to be completed inside the deactivated outer shell, as the core of the particle still retained high catalyst activity.

The kinetics of heterogeneous vapor-phase ammoxidation of lutidine isomers was studied over a Cr2O3-Al2O3 catalyst in a flow system. The reaction was carried out at atmospheric pressure and at a temperature of 360°. 3-Cyano-5-methylpyridine, 4-cyano-3-methylpyridine, 2-cyano-6-methylpyridine, 2-cyano-5-methylpyridine and 2-cyano-3-methylpyridine were produced selectively at low conversion from 3, 5-lutidine, 3, 4-lutidine, 2, 6-lutidine, 2, 5-lutidine and 2, 3-lutidine respectively. 2-Cyano-4-methylpyridine and 4-cyano-2-methylpyridine were produced in same amounts from 2, 4-lutidine. The reaction rate depended on the partial pressure of lutidine and oxygen. Experimental rate data were well interpreted by Langmuir-Hinshelwood mechanism, where the rate determining step was the surface reaction between adsorbed lutidine molecules and adsorbed oxygen molecules.

The structures of four new isoatisine-type alkaloids, spiramines A, B, C, and D, isolated from Spiraea japonica L. fil var acuminata Franch, were determined.

The metabolism of 1-methylhydantoin (2) is described. The major and general metabolic route in mammals, represented by formulae (2)→(7), includes two consecutive stepwise oxidations giving 5-hydroxy-1-methylhydantoin (3) and thence 1-methylparabanic acid (4). Since the first oxidation proved to be stereoselective, the step was thought to be enzymatic. Although enantiomeric products (3a) and (3b)(ca. 3 : 1) could not be separated directly, the mixture was converted into (S)- and (R)-5-(N-benzyloxycarbonyl-L-prolyloxy)-1-methylhydantoins (13a) and (13b) which proved separable and were identified by X-ray analysis of the (R)-diastereoisomer. The regioselective ring-fission of the second product (4) into the methyloxaluric acid (5) is discussed. Two minor oxidative routes from the substrate (2) into sarcosine (9) and parabanic acid (10) were also shown to exist.