Hydrogenation of CO was carried out by using a pulse technique on α-alumina supported Ni, Fe, Co, and Ru catalysts. When a CO pulse was introduced to the catalyst at around 473 K by H₂ carrier gas, hydrocarbons were produced of which chromatographic peaks showed pronounced tailings. The amount of H₂O produced during the slow formation of hydrocarbons was compared with that of hydrocarbons. When CO was pulsed to a catalyst stabilized by the pretreatment with CO pulse, H₂O and hydrocarbons were produced with almost equal reaction rate. On the other hand, when CO was pulsed to a freshly reduced catalyst of Fe, Co, and Ru, H₂O was produced much slower than hydrocarbons. The uptake of oxygen from CO molecule by such catalysts occurred and the metal surface was consequently considered to be partially oxidized. This leads to stabilization of the catalyst surface. In case of Ni catalyst such an oxygen uptake was not observed and the reaction took place in the metallic state. The rate of H₂O formation was equal to that of CH₄. Although the C-O bond dissociation process of the adsorbed CO species was recognized to be a rate-determining step in the hydrogenation of CO over all metal catalysts used, the surface state during the reaction was observed to be different between Ni and other metals such as Fe, Co, and Ru.

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The structure and the decomposition process of R₃(CO)₁₂ dispersed on various oxidei were investigated by use of infrared spectroscopy. Whereas interaction of Ru₃(CO)₁₂, with SiO₂ and ZnO was found to be relatively weak, Ru₃(CO)₁₂ strongly interacted with the surface γ-Al₂O₃ to give a very stable species, which was assumed to be a mononuclear ruthenium carbonyl. The infrared bands due to this Ru carbonyl on γ-Al₂O₃ were located at 2O63 and 199Ocm^-1 and the bands were little affected by evacuation at temperatures up to 25O°C as shown in Fig.4.
Thermal decomposition of the Ru carbonyl on γ-Al₂O₃ followed by H₂ reduction at 45O°C resulted in the formation of Ru catalysts with high dispersion (<9O%) as determined by H₂ chemisorption. The dispersion of Ru/Al₂O₂ catalysts prepared by conventional impregnation using RuCl₃ was low (<5O%) as shown in Fig.5.
Infrared spectra and adsorption measurement of CO and H₂ indicated that CO was adsorbed in linear- and twin-types on Ru/Al₂O₃ derived from Ru₃(CO)₁₂ and that multiple- and twintypesof CO were predominant of Ru/Al₂O₃ prepared from RuCl₃. With increasing dispersion of Ru, the relative amount and the strength of adsorption of twin-type CO increased. The twin-type species was little reactive to hydrogen (Fig.8), indicating that these species rather act as a poison for the hydrogenation of CO over Ru catalyst. The characteristic trend of Ru catalysts that specific activity (turnover frequency) for CO conversion increased with the decreasing metal dispersion in the hydrogenation of CO can be explained by this retardation effect of multiple- and twin-type CO. Infrared bands of adsorbed CO shifted to lower frequencies when Ru was supported on MgO or K₂CO₃-doped Al₂O₃ (Fig.9, 1O), probably due to electron transfer from the support to Ru.

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The reaction mechanism of CO hydrogenation to form hydrocarbons over ruthenium catalysts was investigated. It was confirmed that surface hydrocarbon species accumulated on a limited part of the ruthenium catalyst during the CO-H₂ reaction, while most of the surface were covered by molecularly adsorbed carbon monoxide as shown in Figs.1 and 2. The role of these surface hydrocarbon species in the reaction was examined by the carbon 13 distribution (Fig, 3). The reactivity of deposited carbon formed by Boudouard reaction was also studied by means of carbon 13 (Fig.4). From the behavior of these surface species under the reaction conditions, it was concluded that all of the hydrocarbon products were produced via dissociatively adsorbed CO without CO insertion, and that C₁ intermediate species had high mobility on the catalyst surface enough to react with each other. The effect of the particle size of ruthenium on the reaction was also investigated. The catalyst with smaller particle size exhibited lower activity because of the inhibition of CO dissociation by multiple adsorption of CO.

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The effects of catalyst support and dispersion of ruthenium on the activity and selectivity of CO hydrogenation have been studied. The correlation between the information on the beha vior of adsorbed species, obtained by physicochemical methods such as infrared spectroscopy (IR) and the reactive thermal desorption (RTD), and the catalytic features, determined by a steady-state reaction, have also been discussed.
Hydrogenation of CO at temperatures below 230°C and under pressurized conditions gave hydrocarbons with carbon atoms up to about 40. However, hydrocarbons of C₁₃ and higher did not come out of the catalyst bed during the reaction. They effused when the bed was treated at around 400°C in the flow of inert gas and gave product distributions which follow the Schulz-Flory law. The specific acti vity for CO conversion was dependent upon the metal dispersion, but the temperature and the pressure effect made a proper estimation difficult for the activity of supported ruthenium catalysts. For both SiO₂- and Al₂O₃- supported catalysts, the apparent activation energy of CO conversion was independent of the supports, but dependent on the dispersion (Table 4). It was around 20 kcal/mol and about 35 kcal/mol for the highly dispersed catalysts (H-catalyst) and for poorly dispersed catalysts (L-catalyst), respectively.
The specific activity for the H-catalysts was found to be higher than that for L-catalysts at atmospheric pressure, but an opposit result was found at 6 atm. Product distributions were characterized by the Schulz-Flory distribution law. The probability of chain growth (α) was independent of the supports, but dependent on the dispersion under a pressurized conditions. The a values for the H- and L-catalysts were 0.75 ± 0.02 and 0.87±0.01, respectively. The a values were smaller and the selectivity of methane was larger at 1 atm than at 6 atm (Table 5). The Ru/TiO₂ catalyst was found to produce high-molecular-weight hydrocarbons and less methane ev en at higher temperature and at low pressure.. The correlation of the chain growth hydr ocarbons and the metal dispersion obtained by both IR and the steady-state reaction coincided with each other, but the reactivity of adsorbed CO, obtained from RTD, did not exhibit a good agreement with those deduced from the steadystate reaction.

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Adsorption and hydrogenation of carbon monoxide on iron catalysts were investigated to determine the carrier effect of carbonaceous materials, such as graphite, carbon black and activated charcoal. Activities and product distribution were measured at 623 K and 1.0 MPa by using the synthesis gas whose composition was H₂/CO= 1. Among carbon-supported iron catalysts, a freshly reduced iron catalyst supported on carbon black was most effective in adsorbing an extremely large amount of CO at 298 K. The enhanced CO uptake was most remarkable on a carbon black-supported iron catalyst (1.1%) prepared by impregnation method. The molar ratio of adsorbed CO to Fe exceeded unity, leading to the supposition that “multiple”CO chemisorption occurred on small iron particles at 298 K. Such small iron particles exhibited lower catalytic activity than relatively large iron particles. The activities of carbonsupported iron catalysts were higher than those of alumina and silica supported iron catalysts on a per gram of iron basis, while there was no appreciable difference in the distribution of product hydrocarbons. The activities of some carbon-supported iron catalysts, especially those of activated charcoal-supported one, decayed considerably with time, and the decreased activity was unable to regenerate by H₂ flushing at 623 K and 0.5 MPa. Thus, the deactivation of carbon-supported iron catalysts may not be due to deposition of carbidic carbon on iron active site, which is the case for precipitated iron.

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The C₂∼C₄hydrocarbon synthesis from carbon monoxide and hydrogen has been studied over the rhodium ion-exchanged zeolite catalysts. As their activity and selectivity were strongly dependent on the properties of the supports, the influence of HY and NaY zeolites on the rhodium was studied initially. The observation of the rhodium particle with a high voltage electron microscopy indicated that rhodium, supported on HY zeolite, was highly dispersed. Therefore, the Rh-HY catalyst was more active for hydrogenation than the Rh-NaY catalyst. From the study of infrared spectra, the stretching frequency of carbon monoxide adsorbed on Rh-NaY catalyst was about 25cm^-1 lower than that on the Rh-HY catalyst. The results of the thermal desorption showed that carbon monoxide had a tendency to chemisorb dissociatively on the Rh-NaY catalyst. The binding energy of rhodium (3d_5/2) of the Rh-HY catalyst was large, indicating that the rhodium supported on HY had strong interaction with the zeolite and became low in the electron density. These results suggest that the increase of back donation by rhodium electrons contributes to a strengthening of the rhodium-carbon bond and to a weakening of the carbon-oxygen bond for the carbon monoxide chemisorbed on the Rh-NaY catalyst. The product distribution was also sensitive to the support. Particularly, large amounts of carbon dioxide formed over the Rh-NaY catalyst. The particle size and electronic structure of the rhodium catalysts are dependent on the properties of the supports, and these characters play important roles in controlling the product distribution.

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Hydrogenation of carbon monoxide was carried out over amorphous and crystalline ribbon catalysts of the same composition Fe₂₀Ni₆₀P₂₀. The initial distribution of product hydrocarbons was strongly dependent on the partial pressure of carbon monoxide, showing the s electivity for higher hydrocarbons with increasing partial pressure of carbon monoxide. The amorphous catalysts yielded C₂ to C₅ hydrocarbons at much higher rates than the crystalline catalyst which showed the higher selectivity to methane.
When high conversion of carbon monoxide was carried out, the rates of olefin production decreased with increasing residence time on both the amorphous and the crystalline catalystst. The distribution with the crystalline catalyst followed the Schulz-Flory model.
Since the propagation reaction of ethylene to yield propylene is experi mentally ascertained over the amorphous catalyst, a model simulating the reaction was constructed to explain the experimental product distribution. The calculated results from the proposed model show that the propagation reaction of olefins may be one of the most plausible explanations for the experimental distribution which was different from the SF distribution.

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Synthesis of hydrocarbons from syngas utilizing mixed catalysts prepared by physically combining a methanol synthesis catalyst composed of copper oxide, zinc oxide and alumina with zeolite (H-Y or H-ZSM-5) was studied under pressurized condition. At pressures higher than 10 kg/cm₂G hydrocarbons were formed beyond the thermodynamical limit of methanol formation. It is interpreted to be due to the rapid conversion of methanol formed to hydrocarbons on zeolite. The major product was a mixture of aliphatic hydrocarbons with 3 to 6 carbon atoms with minor amount of C₁ and C₂ hydrocarbons at temperatures as high as about 350°C. Both H-13 Y and H-ZSM-5 zeolites yielded aromatic hydrocarbons (mainly polymethylbenzenes)with fairly high selectivities from methanol when they were used without the methanol catalyst. However, both H-Y and H-ZSM-5 gave little aromatics if they were used for syngas conversion in combination with the methanol catalyst containing copper oxide. The operational factors such as reaction temperature, reaction pressure, residence time, H₂/CO ratio or catalyst composition exhibited marked effects on hydrocarbon yield but not on hydrocarbon distribution. It has been pointed out that one of the major reasons for the lack of aromatics in the products is the quick hydrogenation of olefins, which are the intermediates of the reaction from methanol to aromatic hydrocarbons, by hydrogen on the methanol catalyst.

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Methanol and a small amount of ethanol were catalytically produced (in more than 90%selectivity) under an atmospheric pressure of CO-H₂ over Pt, Pd and Cu catalysts supported on the selected metal oxides such as La₂O₃, Y₂O₃, Nd₂O₃ as rare earth oxides and MgO and CaO as alkali metal oxides. The relative rates of methanol formation decreased in the orde r; Pd/La₂O₃ PtiLa₂O₃ Cu/La₂O₃, which was in parallel with the decreasing order of their hydrogenation activities.. The kinetic parameters for methanol and methane formation were obtained in the atmospheric pressure CO-H₂ reactions over Pd/La₂O₃ as V_OH3OH=k1 P_H2 Pco^0.4 exp(-14000/RT) and V_CH4=-k₂P_H2^0.8Poo-^-0.4exp(-29000/RT). The Pd/La₂O₃ catalyst was app lied to the higher pressure syngas conversion and gave higher yields and selectivities for methanol production, in comparison with those over Pd/SiO₂ catalyst.
The specific promoting effects of these basic oxide supports for the methanol synthesis were considered from the kinetic and IR spectroscopic studies to be based on the formation of a formate ion intermediate in the reaction between associatively chemisorbed CO on Pd and Pt and basic sites such as OH^-and O^2-, which might be converted by hydrogen to methanol. The effects of addition of some other metal salts such as MnCl₂, ReCl₅, NbCl₅ and NaOH, which could be incoorporated in the catalytic preparation showed that the Re and Mn salts enhanced the yields of methanol specifically and that the Re addition improved the ethanol selectivities in the oxygenated product in the CO-H₂ reaction catalyzed by Pd/La₂O₃ and Pt/La₂O₈ catalysts.

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Preparation of zeolite catalysts for synthesis of lower olefins with high selectivity and long life have been studied with the purpose of a brief crystallization time and reproducibility in mind.
Cocoon-shaped zeolite crystallites [I] with a length of 14 μ, which had the performance of ca.75% selectivity of C₂∼C₄ olefins, could be synthesized with a crystallization time of only 2h at 187°C, using tetramethyl (or tetraethyl) ammonium hydroxide (TMAH) as the modif ier. TMAH was used in amount of 1/30∼1/3.8 molar ratio to alkali with the conditions of Si/A1atomic ratio of 6.5∼11.5, and alkali/Al atomic ratio of 7. When a portion of finely pulverized [I] was added as seed crystals to the mixture before crystallization, rice-shaped zeolite crystallite weres obtained reproducibly. In the case of 9 wt% addition of seed crystals [II]toward the formed zeolite without seed crystals, the crystal size reduced to 1.3, u in length and ca.1/70 in volume, and the shape became uniform as compared with J. On the basis of X-ray diffraction patterns, these zeolites were considered to be novel type crystals composed of offretite and erionite. The novel zeolite [II] catalyst exhibited more than 80% selectivity of C₂∼C₄ olefins with the life twice as long as [I]. Similar effect was found by the use of a mixture of γ- and -αlumina instead of the seed crystals. Furthermore, when small amounts of Rh or Ru had been impregnated previously on the alumina mixture, the catalyst performance was further improved with respect to the ethylene selectivity and the life.

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Selectivity regulation in the conversion of methanol to hydrocarbons on several zeolites was studied. The model analysis of reaction gave the following assumptions for the catalysis of H-Y or H-Moldenite in comparison with H-ZSM-5:
( 1 ) The concentration of acid site is very high.
( 2 ) The degree of unsaturation of adsorbed hydrocarbon species is high.
( 3 ) Therefore, the adsorbed hydrocarbon species with 3 or more ca r bon atoms polymerize, without desorbing, to form coke. The hydrogen which evolved during the coking, reacts with C₁- and C₂adsorbed species to form CH₄ and C₂ hydrocarbons.
While the reactions on the zeolites which carried sulfided nickel (Ni (S) ) on them gave results quite similar to those on the unearned ones under nitrogen atmosphere, the reactions under pressurized hydrogen gave markedly different results. On a Ni(S ) /H-ZSM-5 catalyst the selectivity of CH, increased by about 100 times to around 90% with an unchanged conversion (Table 3). On a Ni ( S )/H-Moldentite catalyst the rate of deactivation decreased to one tenth or less, compared to that in the reaction of nitrogen atmosphere, accompanied by the decrease in the selectivity of coke formation to about one tenth. At the same time, the selectivities of Ca₃∼C₇ aliphatic hydrocarbons and aromatic hydrocarbons increased from 2.4%and 0% to 26.6% and 15.4%, respectively (Table 4).

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The catalytic carbonylation of diaryliodonium salts ([Ar₂I]X)by a palladium catalyst has been investigated. In the presence of an alcohol and a base, diphenyliodonium bromide ([Ph, I]Br)gave the corresponding benzoate and iodobenzene quantitatively.
The reaction took place rapidly under mild cond itions such as an ambient temperature and an atmospheric pressure of carbon monoxide (Table 2). The carbonylation of [Phj]Br proceeded by two consecutive steps the direct carbonylation of [Ph₂I]Br to produce equimolar amounts of methyl benzoate and iodobenzene and the consequent slow carbonylation of iodobenzene to methyl benzoate (Fig.1).
Various palladium cataly sts were effective for the reaction (Table 3) and both trialkylamines and potassium acetate were effective as bases (Table 4). The addition of triphenylphosphine retarded the carbonylation and formed a small amount of by-products such as benzene and bromobenzene (Table 5). In addition, alkoxycarbonylation (Table 6) and amidation (Table 7)of various ([Ar₂I]X) have been studied. Aromatic carboxylic derivatives and aryl iodides were obtained quantitatively.

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The carbonylationo f diphenylacetylene a[4a]w ith Rh₄ (CO)₁₂ triethylamineg ave 3, 4 dipheny1-5-ethylidene-2(5H) - furanone [5] in a 5% yield, in which the ethylideneg roup was derived from the amine. Addition of ethylene to the reaction system resulted in the formation of 3, 4 -dipheny1-5-ethyl-2(5H)-furanone [6a] (16%). By usingp rotic solventss uch as alcohols and aqueousa cetone, t he yield of [6a] was increasedr emarkably( Table1 ). Amongs everal rhodiumc arbonylc omplexesa n d their precursorsu sed as the catalyst (Table2 ), the catalytic, ctivities of Rh₄ (CO)₁₂ and Rh₆ (CO)₁₆ were prominent. Similarly, the carbonylationo f 2butyne gave 3, 4 -dimethy1-5-ethy1(-52 H )-furanone [6b]in a 58% yield, and that of 1-phenyipropyneg ave 5-ethyl-3-methyl-4-phenyl-2(5H)-furanone [6c] and 5-ethy1-4-methy1-3ptieny1-2(H5) -furanone [6d] in 48% and 4% yields, respectively, i ndicatingt he reactiont o be regioselective. At higher temperatures( 150∼220°C)[6a] was mainlyo btainedby the carbonylation of [4a] in ethanol, but at lowert emperatures( 100∼125°C )3, 4 -dipheny1-5-ethoxy2 (5H)-furanone [15] and 3- ( ethoxycarbony1)-2-phenylindanone w[1e6r]e obtained as byproducts, , w hichw ere formed by the participationo f ethanol in the carbonylation. Possible mechanismsfo r the formationso f [6] and [16] are showni n Scheme1 and 2.

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Synthetic and kinetic invstigations have been carried out on the formation of phenylacetic acid in the carbonylation of benzyl alcohol catalyzed by RhC133H 20 in the presence of benzyl iodide. The carbonylation was carried out at 110∼160°C and under 10∼50 kg/cm' CO in the liquid phase using the autoclave equipped with a high-pressure gas reservoir, and the reaction products were analyzed by gas chromatography; gas chromatography-mass spectrometry, NMR-, and IR-spectrometries.
The produc t distributions in the carbonylation were remarkably affected by various reaction factors, such as the amounts of RhCl₃⋅3H₂O and benzyl iodide, the concentration of benzyl alcohol, partial pressure of CO, reaction temperature, and reaction time, the optimum condilions for the synthesis of phenylacetic acid being- benzyl alctthol: RhCl₃⋅3H₂O: benzyl iodide: solvent = 1.0: 6.3 × 1.1 × 1 0': 8×10^-1 (molar ratio), ca.30 kg/cm², ca.140°C, and ca.90 min, respectively. Tile conversion I of benzyl alcohol and the selectivity to phenylacetic acid under these conditions lead to 100 mol% and 94 mol%, respectively. In the initial stage of the carbonylation, diberizyl ether (DBE) and benzyl phenylacetate (BPA) were mainly produced, which were gradually converted to phenylacetic acid. Toluene and bibenzyl were formed in small amounts as the by-products. The kinetics of the carbonylation was studied by measuring the rates of CO consumption under the different reaction conditions. The rate equation was obtained as rate =k[Rh complex] [benzyl iodide]. The rate-determining step in this carbonylation is thus the oxidative addition of benzyl iodide to Rh ( I ) complex as in the case of the carbonylation of CH₃OH proposed by Forster. The fact that the carbonylation of a binary mixture of benzyl alcohol and CH₃OH gave predominantly the carbonylation products of benzyl alcohol indicates that benzyl alcohol was more easily carbonylated than CH₃OH. Although the rate of the carbonylation of benzyl alcohol was considerably faster than that in the case of CH₃OH, the active catalyst species, [Rh (C0)₂I₂]-, may be the same in both case s, and the catalytic cycle conducted by the species is proposed.

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Chlorosulfuric acid showed a high catalytic activity in the copolymerization of carbon monoxide with formaldehyde using trioxane or paraformaldehyde as a formaldehyde source. The copolymer obtained was separated into acetone-insoluble portion (white powder) and acetone-soluble portion (oil). The maximum yield of the acetone-insoluble copolymer was obtained when the copolymerization was carried out at 180°C. The ratio of carbonyl group to methylene group (CO/CH₂) of the acetone-insoluble copolymer was between 0.88and 0.94. Dichloromethane was found to be a good 'solvent for the copolymerization. The methanolys is products of the copolymer showed that the copolymer contained the structural unit of -CO⋅-CH₂O-. as a major component together with the structural units of -COCE₂OCH₂COO- [D]and -CH₂O-. The content of the structural unit [D] of the copoly mer increased with an increase in the pressure of carbon monoxide, the amount of the catalyst and the reaction temperature. The content of the unit [ D ] was higher in the acetone-soluble portion than in the acetone-insoluble portion.

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Carbonylation of formaldehyde by CO (1atm) was carried out at room temperature using [Cu (CO)n ]+ or [Ag (CO)₂]+ in strong acids as a catalyst. Glycolic acid or its ester was obta ined in high yield without side reaction. Rate constants of carbonylation increased 30 times in the presence of the catalysts (Fig.3∼6). The sufficient concentrations of the copper ( I ) and silver compounds were 0.2 and 0.4 mol/l, respectively, in sulfuric acid, and 0.05 mol/l in boron trifluoride hydrate to carry out carbonylation rapidly. The CO concentration in the catalyst solution decreased in the order:
The rate of carbonylation decreased in the same order at the same molar concentration of the copper ( I ) or silver compound. The rate decreased with the decrease of the acid concentratio n in each system. Carbonylation hardly proceeded in solutions less concentrated than 84.5%H₂SO₄, and H₂O/BF₃= 2. After the reaction, methyl glycolate was separated by vacuu m distillation and the catalyst solution was used again.

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Equilibrium constants were evaluated in H₂ O and MeOH-H₂O solutions saturated with Ca (OH)₂ for 1 to 1 complex formations between dissolved Ca (OH)₂ and formaldehyde (C_1A ); a feed stock for formose formation, known accelerators such as 2-hydroxyacetophenone (HAP), DL-glyceraldehyde (C_3A ), 1, 3-dihydroxyacetone, D-glucose (Glu), and D-fructose, or 2, 3dihydroxypropiophenone (DHPP); a C_1A addition product to HAP. The initial rate of C_1A conversion to formose was measured using HAP, C_3A and Glu as accelerators, in the presence of Ca(OH)₂ or NaOH at the pH region of 11.5 to 12.5, in order to elucidate kinetically whether the complex between dissolved Ca (OH)2 and accelerator might enhance the formose f ormation. The order of acceleration efficiency and that of complex formation constants were strictly in reverse, and DHPP revealed a great acceleration effect in spite of no binding ability to Ca (OH)₂. Moreover, the reaction kinetics were first order each with [uncomplexed accelerator], [C_1A], and [OH-]. These results indicate that the formose formation in a high pH region proceeds mainly through OH- catalyzed aldol reaction.

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Palladium (0) -phosphine complexes catalyzed the cyclodimerization of methylenecyclopropanes and carbon dioxide with opening of the three membered ring to give furanones. Methylenecyclopropanes having dialkyl-substituents on the exo-methylene gave exclusively 3, 3-dialky1-4methylenetetrahydro-2-furanone by Pd (0) -PPh, system. On the other hand, 4-methyl-5, 5dialky1-2 (5H) -furanone was formed as the major product in the presence of Pd (Ph₂ PCH₂ CH₂ ⋅ PPh₂) ₂ ' A considerably high yield of 3-alkyl-4-methyl-2 (5H) -furanone and 4-me thyl-5-alkyl-2 (5H) -furanone was realized on the reaction of carbon dioxide and methylenecyclopropanes having monoalkyl substituent on the exo-methylene by either catalytic system. The CO₂ methylenecyclopropane reaction occurred scarcely when a substituent was on the ring. Reaction scheme involving trimethylenemethane complex as an intermediate was proposed.

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Reactions of carbon dioxide with aliphatic primary or secondary amines readily gave the corresponding ammonium carbamates in variety of solvents. The used of carbamic acids would appear to offer certain advantages to the study of the carbon dioxide incorporation into organic compounds under mild conditions.
Reactions of 2-methoxy oxiranes or a-halogenated acylophenones with carbon dioxide and aliphatic amines in methanol gave corresponding 3-alkyl-4-hydroxy-2-oxazolidinone derivatives.3-Isopropyl-4-hydroxy-5, 5-dimethy1-4-pheny1-2-oxazolidinone was thus obtained from 2-methoxy3, 3-dimethyl-2-phenyloxirane or α-bromisobutyrophenone with isopropylamine. The structure of the oxazolidinones was deduced from their IR spectra which show strong carbonyl bands at 1740 cm^-1.
Acid hydrolyse s of the oxazolidinones afforded a-hydroxyisobutyrophenone. Catalytic reduction in acidic methanol and following hydrolysis gave corresponding 1-alkylamino-1-pheny1-2propanols. The mechanism of the oxazolidinone formation is discussed.

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Free anionic additions of oxirane and its alkyl, aryl and halomethyl derivatives with carbon dioxide catalyzed by potassiim carboxylates or carbonates have been achieved by the addition of a crown ether, resulting in the formation of five-membered cyclic carbonates as the main products. In the absence of carbon dioxide, the potassium salts initiated the polymerization of oxirane and alkyl- and aryloxiranes to afford polyethers having the carbonyl end group at one of the chain ends. Halomethyloxiranes were not polymerized under the same conditions and reacted stoichiometrically with potassium acetate to give glycidyl acetate in high yields. The reactions between halomethyloxiranes and potassium ethyl carbonate gave a variety of products including linear and cyclic carbonates. A reaction scheme is proposed to interpret all the results consistently.

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The alternating copolymerization of propylene oxide and carbon dioxide was conducted at 60°C with some new types of catalysts. The catalysts employed were metal oxides-supported diethylzinc (A), metal salts of acetic acid (B), the reaction products of zinc hydroxide and dicarboxylic acids (C), and metal oxides-supported zinc, cobalt and aluminum halides (D). In the case of the copolymerization with the A-series catalysts, the activity increased to a great extent with an increase in the pore diameters of metal oxides. Among the B-series catalysts, only cobalt and zinc acetates gave the alternating copolymer. The addition of acetic acid to these systems hardly diminished the copolymer yield, but the number average molecular weight of the copolymer decreased in proportion to the concentration of acetic acid. In the case of the copolymerization with the C-series catalysts, the activity was strongly dependent upon dicarboxylic facids used Aliphatic dicarboxylic acids, especially glutaric acid, showed very high activities. On the other hand, the D-series catalysts also showed considerably high activity, although none of these metal halides showed any activity without supporting on metal oxides. A plausible mechanism for the alternating copolymerization with these catalysts was proposed.

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When carbon is heated in the presence of alkali carbonates, carbon monoxide is evolved quite efficiently at temperature around 800°C. The overall reaction does proceed according to the following equation.

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Carbon monoxide hydrogenating characteristics of A-, B- and C-series catalysts containing Re have been studied with special attention to the selectivity for the formation of alcohols, where A-series=mainly Re-metal oxide catalysts, B-series=mainly Re-binary metal oxide mixture catalysts, and C-series=catalysts containing Fe.
Majority of the A-series catalysts exhibited measura ble activities with high selectivities for producing hydrocarbons. However there were several catalysts with better selectivities for producing alcohols. Results of activity tests on the B-series catalysts showed an outstanding effect of ZnO in raising the selectivity of methanol formation. A nitrogen-treated Re-Fe catalyst was prominent in the C-series catalysts, exhibiting a stable activity and a good selectivity for producing alcohols.

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Nickel complexes, NiY₂L₂ (Y =Cl or C₂H₅; L=1/2 bpy (2, 2'-bipyridine), 1/2 dpe (1, 2-bis (diphenylphosphino) ethane), or dpm (bis (diphenylphosphino) methane), catalyzed the forma tion of diary' ketones, RCOR, from RMgBr (R =C₆H₅, P-FC₆H₄, or p-CH₃C₆H₄), RBr, and CO in diethyl ether or THF at 10∼45°C. A C-C coupling reaction between RMgBr and RBr to form R-R accompanied the ketone synthesis, but the molar ratio of R-R to RCOR could be controlled under 0.07 by using NiCl₂ (dpm) 2 as the catalyst.

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Vapor-phase carbonylation of methanol to acetic acid under atmospheric pressure has been investigated with nickel-based catalysts supported on an active carbon. The reaction-gas mixture composed of 17 vol% CH₃0H, 66 vol% CO, 2.5 vol% CH₃ I, and 14 vol% N₂ was allowed to flow through the catalyst bed at a space velocity of 700 in the temperature range of 260∼360°C. Acetic acid formed as the major product accompanied by small amounts o f methyl acetate and methane on the catalyst of 4.8% Ni-2.5% La₂O₃ -1.2% Ru, 5.0% Ni-2.8% La₂ O₃, 1-10% Ni or even NiCl₂ (1% as Ni). In the case of 10% Ni catalyst, the maximum space-time yield of acetic acid (3.93 mol⋅ l^-1⋅h^-1) was obtained at 320°C under complete conversion of methanol. These catalysts surpassed the 2% Rh catalyst supported on the same active carbon in the maximum yield and selectivity of acetic acid.

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The polymer-immobilized rhodium complex prepared from rhodium (III) chloride and the chelate-resins with iminodiacetic acid moieties (catalyst I ) showed a catalytic activity for hydroformylation of 1-hexene in ethanol at 100°C under 20 atm of HE and 20 atm of CO. T he normal/branched ratio in produced aldehyde was 2.3 in this reaction. The same chelate-resin and (acetylacetonato) dicarbonylrhodium ( I ) gave the immobilized rhodium ( I ) complex catalyst (catalyst II), showing a much higher activity than the catalyst I for the reaction under the similar conditions as seen in Table 1. The normal/branched aldehyde ratio was 0.7.

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The formose formation, the condensation of formaldehyde producing a mixture of carbohydrates and their analogs, is of great importance in view of the production of edible carbohydrates from a simple material. Quaternized poly[p-[2- (diethylamino) ethyl]styrene] gel (OH type) was found to show catalysis for the formose formation with high efficiency. Formaldehyde consumption was high when the catalyst with high extent of quaternization or low extent of crosslinking was employed. Formose obtained by these catalysts consisted of similar components including 2-C- (hydroxymethyl) glycerol.

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Oxidation pretreatment of solid carbon and the subsequent ion-exchanging of the nickel catalyst greatly increase its hydrogenation reactivity to methane. In the present work a complete gasification was observed at>6 wt% of the nickel content. The comparative experiments, using the ion-exchanging vs. impregnation of the catalyst on oxidized or unoxidized active carbon, suggested that an increase in the reactivity was not attributable to an increase in the dispersion of the catalyst particles, but rather to an enhancement of the reactivity of carbon itself which was related probably to decomposition of the surface oxides. However, the amount of methane formed was much larger than that of carbon atoms constituting the surface oxides, indicating that the gasification of these carbon atoms activated the reaction of their peripheral atoms with hydrogen.

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