Reactions of carbon monoxide with unsaturated fatty acids and derivatives: A review

The important reactions of carbon monoxide with unsaturated fatty derivatives that are reviewed in this paper include hydroformylation (the oxo reaction), Koch carboxylation and Reppe carbonylation. With oleic acid as a substrate, the products are C₁₉ bifunctional compounds e.g., formyl- or carboxy-stearic acid. Double bond isomerization before carbon monoxide addition is characteristic of these catalytic reactions; additionally, rearrangement to introduce methyl branching occurs in the Koch carboxylation. Isomerization does not occur when a rhodium-triphenylphosphine catalyst replaces cobalt in the oxo reaction. Properties of the C₁₉ dicarboxylic acids differ and depend upon method of preparation: Many areas of application have been reported for C₁₉ compounds-lubricants, plasticizers, polyurethanes, epoxy resins, leather and other coatings, unsaturated polyester resins and transparent polyamide plastics. Presented at the AOCS Meeting, Los Angeles, April 1972. N. Market. Nutr. Res. Div., ARS, USDA.     

Ni/PHAC催化甲醇羰基化合成乙酸工艺研究

以自制的酚醛树脂基活性炭(PHAC)负载镍为催化剂、碘甲烷为助催化剂,研究了在连续固定床反应器中催化甲醇碳基化合成乙酸的反应。探讨了反应温度、液体进料空时、甲醇与一氧化碳配比及加水量等反应工艺条件对甲醇羰基化反应及乙酸收率的影响,优化了反应的工艺条件。结果表明：反应工艺条件对甲醇羰基化反应及乙酸的收率影响较大,在系统压力为1．0MPa,反应温度558K,液体进料空时为10gcat．(mo1．h^-1)^-1,V(H20)：V(CH30H)＝3：100,n(CO)：n(CH30H)：n(CH3I)＝80：40：1的条件下乙酸收率最高达到了67．1％,而羰基化产物总收率可以达到79．1％,甲醇转化率可以达到93．8％,羰基化产物总收率和乙酸收率明显高于文献报道的同类催化剂。     

An effective rhodium catalyst system on the synthesis of acetic acid from methyl formate

Rh/Lil/SnR₄ is an effective catalyst system for the conversion of methyl formate to acetic acid under carbon monoxide pressure. The effects of solvent and initial CO partial pressure on the turnover rate of the reaction were investigated. The possibility of replacing some of the iodide promoters by tin compounds has been probed.     

A highly efficient catalyst for direct synthesis of methyl acrylate via methoxycarbonylation of acetylene

A non-petroleum approach for the catalytic synthesis of methyl acrylate via methoxycarbonylation of acetylene with carbon monoxide and methanol as nucleophilic reagent has been studied under various conditions. Pd(OAc)₂/2-PyPPh₂/p-tsa was found to be a highly efficient catalytic system. The types of phosphorus ligands and their concentration was a determinative factor for catalytic activity. Mono-dentate phosphorus ligand such as triphenylphosphine has no activity while 2-(diphenylphosphino)pyridine with a mixed N-P bidentate structure has an excellent activity. Catalytic performance of acids depends on their acidic strength and coordinative property. Among all acidic promoters, p-toluenesulfonic acid displayed an excellent performance. Other parameters such as solvent polarity and initial pressure of carbon monoxide have also important influences on the hydroesterification of acetylene. It is beneficial for the reaction that the solvents have a high polarity. At low pressure of carbon monoxide, to high active palladium catalyst, the reaction easily proceeded. However, at high pressure of carbon monoxide, acetylene will transfer from solution to gas phase, resulting in lower conversion of acetylene. In addition, due to steric hindrance of alcohols, methanol has a highest activity in hydroesterification of acetylene in low carbon alcohols. Under the optimal reaction conditions, 99.5% of acetylene conversion and 99.7% of selectivity toward methyl acrylate as well as 2,502 h^?1 TOF were achieved.     

Carbonylation of dimethyl ether on solid Rh-promoted Cs-salt of Keggin 12-H3PW12O40: A solid-state NMR study of the reaction mechanism

The carbonylation of dimethyl ether (DME) with carbon monoxide on Rh-promoted cesium salt of 12-tungstophosphoric acid, Rh/Cs₂HPW₁₂O₄₀ (HPA), has been studied with ¹³C solid-state NMR. The bi-functional character of Rh/Cs₂HPW₁₂O₄₀ catalyst in halide-free carbonylation of DME has been directly demonstrated. The activation of the C–O bond of DME proceeds on Brønsted acid sites of HPA with the formation of the methyl group attached to the surface of HPA (methoxy species), whereas the role of rhodium consists in trapping carbon monoxide from gaseous phase and a transfer of CO to the center of DME activation, acidic OH-group of the catalyst, in the form of rhodium carbonyls. The lattice of Cs₂HPW₁₂O₄₀ makes it possible to locate these two different active centers in close proximity to each other, e.g., on two adjacent oxygen atoms, terminal and bridging, of one Keggin anion, thus facilitating the insertion of carbon monoxide from rhodium carbonyl into the C–O bond of methoxy-group to produce the acetate group bound to the Keggin anion. The latter offers finally methyl acetate under the interaction with DME, the intermediate surface methoxy-groups being restored.     

Promotion effects of Lewis acid/(CH3)4NI on [Co(CO)4]ˉ-catalyzed C–N bond activation in the carbonylation of trimethylamine

An effective synthesis of N,N-dimethylacetamide (DMAc) via NaCo(CO)₄-catalyzed carbonylation of trimethylamine is reported. Lewis acid (AlCl₃, FeCl₃, BiCl₃, InCl₃ etc.) and (CH₃)₄NI were used as promoters to activate the unreactive sp³ carbon–nitrogen (C–N) bond of trimethylamine and a significant increase in catalytic activity was observed. High selectivity (98%) and yield of DMAc (96%) were obtained under relatively mild reaction conditions. Based on the role of promoters and the products in the reaction, a plausible mechanism that contains two different ways of activating C–N bond was proposed.     

Low-Pressure Carbonylation of Benzyl Bromide with Palladium Complexes Modified with PNS (PNS = Ph2PCH2CH2C(O)NHC(CH3)2CH2SO3Li) or P(OPh)3. Structural Identification of Palladium-Catalyst Intermediate

The catalytic activities of two palladium complexes with water soluble phosphine PNS (PNS = Ph₂PCH₂CH₂C(O)NHC(CH₃)₂CH₂SO₃Li) (I) and phosphite P(OPh)₃ (II) were tested in the carbonylation of benzyl bromide in methanol at 40–50°C and 1 atm of CO. The first catalyst, (I), was formed in situ from PdCl₂(cod) and PNS, the second one, (II), was based on the PdCl₂(P(OPh)₃)₂ complex. At the ratio of [NEt₃]:[PhCH₂Br] equal to 2.5 the yields of phenylacetic acid methyl ester were 83–86% in the carbonylation with PNS and 100% in the carbonylation with P(OPh)₃. The palladium catalyst with P(OPh)₃ produced under the same conditions 70% of phenylacetic acid methyl ester in the carbonylation of benzyl chloride and 60% of 2-methylphenylacetic acid methyl ester in the carbonylation of 1-bromoethylbenzene. The lower rate of carbonylation of 1-bromoethylbenzyl bromide in comparison to that of benzyl bromide was explained by the lower rate of the substrate oxidative addition step leading to palladium benzyl complexes. Two palladium benzyl complexes, cis-PdBr(PhCH₂)(P(OPh)₃)₂ and trans-PdBr(PhCH(Me))(P(OPh)₃)₂ have been isolated and characterized (X-ray, ³¹P and ¹H NMR).     

Phosphorus Acids as Highly Efficient Promoters for the Palladium-Phenanthroline Catalyzed Carbonylation of Nitrobenzene to Methyl Phenylcarbamate†

A new family of promoters, based on phosphorus acids, is reported for the catalytic carbonylation of nitrobenzene to methyl phenylcarbamate by palladium-phenanthroline complexes. With the new promoters, unprecedented reaction rates (TOF up to 6000/h) and catalyst stability (TON up to 10⁵) could be reached. The best promoter is phosphoric acid, which is also very cheap, nontoxic and easily separable from the reaction products.     

A study of the water–gas shift reaction in Ru-promoted Ir-catalysed methanol carbonylation utilising experimental design methodology

The water–gas shift reaction occurs competitively to the main reaction of the Ir-catalysed methanol carbonylation process. To study the effect of seven factors including temperature, pressure, iridium, ruthenium, methyl iodide, methyl acetate and water concentrations on the formation of hydrogen and carbon dioxide as a result of the water–gas shift reaction and other side reactions in the carbonylation of methanol to acetic acid, the experimental design method combined with response surface methodology (RSM) was utilised. Central composite design at five levels (with α=1.63) was used to design experiments. A quadratic model that included the main and interaction effects of variables for H₂ and CO₂ formation was developed. For two responses, R² was in reasonable agreement “Adj-R²”. Furthermore, statistical tests confirmed the accuracy and the precision of models developed in this research. For CO₂ formation, pressure, iridium and methyl iodide concentrations and for H₂ formation, water and iridium concentrations had the most pronounced effects. Optimum conditions to minimise H₂ and CO₂ and CH₄ formation were determined as follows: temperature of 189 °C, pressure of 32.0 bar, iridium content of 859 ppm, ruthenium concentration of 528 ppm, methyl iodide content of 8.68 wt%, methyl acetate concentration of 23.9 wt% and water content of 6.49 wt%. Ultimately, an experiment at optimum conditions revealed satisfactory agreement between the experimental and predicted data.     

LaCl3-based catalysts for oxidative chlorination of CH4

LaCl₃ is an active, selective and stable catalyst for oxidative chlorination of methane to methyl chloride. Selective conversion to methyl chloride can be achieved by limiting methane conversion, for example, by using an excess of methane in the feed. Methylene chloride and carbon monoxide are the main side products at higher methane conversion levels. Transient OCl⁻ anion, formed by oxidation of Cl⁻ in LaOCl and LaCl₃ with molecular oxygen, is proposed to be the active site for the initial step of methane activation. CO _x formation is proposed to proceed through the formation of adsorbed multiply substituted chloromethanes.     

Preparation of CuCl/C catalyst for the synthesis of dimethyl carbonate: Effects of calcination temperature

Activated carbon supported cuprous chloride, a rarely examined catalyst, was prepared and applied to the oxidative carbonylation of methanol. The catalyst was prepared by impregnation. Water insoluble cuprous chloride was dissolved in hydrochloric acid. The effects of the calcination temperature in preparing the catalysts were examined. The results showed that, as the temperature was increased, the major surface species in the catalyst shifted from CuCl₃²⁻ to CuCl, then to Cu₂Cl(OH)₃, and finally to Cu⁰. Cuprous chloride appeared to be the active species for the production of dimethyl carbonate (DMC), and maximum amount of cuprous chloride in the catalyst occurred at a calcination temperature of 300 °C.     

Zur Rhodium-katalysierten Carbonylierung aromatischer Nitroverbindungen zu Isocyanaten. I. Katalysatoren und Reaktionsbedingungen

On the Rhodium-catalyzed Carbonylation of Aromatic Nitrocompounds to Isocyanates The carbonylation of aromatic nitro compounds with carbon monoxide giving isocyanates at normal pressure and 100°C in the presence of rhodium complexes and a co-catalyst has been studied. Isocyanates can be obtained in o-dichlorbenzene with a selectivity of 50%. The main by-product is the corresponding amine which destroys the co-catalyst. Di-μ-chlorotetracarbonyldirhodium(I) is the active rhodium catalyst as the co-catalyst reacts with the ligands of other rhodium complexes producing this complex in all cases. The most active co-catalysts are MoCl₅ and VCl₄. Voluminous substituents in position 2 of the nitro compound increase the reaction rate, whereas substituents in position 4 have no unfluence. The reaction rate is independent of the carbon monoxide pressure.     

Easy,Green and Safe Carbonylation Reactions through Zeolite‐Catalyzed Carbon Monoxide Production from Formic Acid

Zeolites with the right shape and acid site density and strength, such as certain ZSM‐5 forms, were able to cleanly decompose formic acid to carbon monoxide (CO), and the latter could be directly used in palladium‐catalyzed carbonylation reactions. A simple two‐reactor system was designed to produce CO conveniently and then further react this gas in a safe way. The two‐reactor system is particularly cheap, easy to set up and use. In addition, the carbonylation conditions without pressure allowed for very efficient CO incorporation, with only 1% of palladium(II) chloride (PdCl₂) and Xantphos.

     

利用工业废气常压氯苄羰化制备苯乙酸

研究了含有一氧化碳的工业废气（化肥厂铜氨再生气及黄磷尾气）经过简单处理，用八羰基二钴为催化剂羰化法制备苯乙酸，苯乙酸产率达９０％，产品不需要精制，纯度可达９９．９％，其应用于青霉素发酵中效果良好。溶剂可以反复使用，催化剂的回收率在９０％以上。     

The deep oxidation of chemical warfare agent models: facile catalytic oxidative cleavage of phosphorus-carbon and sulfur-carbon bonds using dioxygen

In water, metallic palladium on carbon was found to catalyze the deep oxidation of organophosphorus and organosulfur compounds by dioxygen at 90°C in the presence of carbon monoxide. This system presents the first examples of catalytic cleavage of phosphorus-carbon bonds. Starting with trimethylphosphine oxide, the phosphorus-containing products formed by sequential P-C cleavage were dimethylphosphinic acid, methylphosphonic acid, and phosphoric acid. A similar reaction sequence was also observed for triethylphosphine oxide, except that products formed by partial oxidation of the ethyl groups, such as phosphonoacetic acid, were also seen as intermediates. The deep oxidation of dimethyl and diethyl sulfides proceeded through the intermediacy of the corresponding sulfoxides. For the methyl derivatives, the ease of oxidation decreased in the order: (CH₃)₂S>(CH₃)₂S O>(CH₃)₂SO₂ and is consistent with the system acting as an electrophilic oxidant. This revised version was published online in July 2006 with corrections to the Cover Date.     

Carbonylation of Dinitrotoluene to Dimethyl Toluenedicarbamate; High Efficiency of Phosphorus Acids as Promoters for the Palladium‐Phenanthroline Catalytic System

Phosphorus acids are excellent promoters for the palladium‐phenanthroline catalyzed carbonylation of 2,4‐dinitrotoluene to 2,4‐toluenedicarbamate. For the first time, all intermediate nitrocarbamates and aminocarbamates have been independently synthesized and their amount after every catalytic reaction precisely quantified. An extensive optimization of all experimental variables has been carried out. The best acids are phenylphosphonic and 4‐tolylphosphonic acids. The addition of 2,2‐dimethoxypropane as an internal drying agent is highly beneficial. The addition of an amine derived from the starting dinitroarene increases both rate and selectivity of the carbonylation reaction. The complexes [Pd(Phen)₂] [SbF₆] and [Pd(Phen)₂][BAr^F₄] [Ar^F=3,5‐(CF₃)₂C₆H₃] have been prepared for the first time. The latter displays a markedly higher solubility than all other [Pd(Phen)₂]²⁺ complexes. The effect of several possible promoters has also been investigated. Under the optimized experimental conditions, a 77.6% selectivity in dicarbamate was obtained when working at a molar ratio dinitrotoluene/Pd=2920. At the end of the reaction, the dicarbamate spontaneously precipitates out of the solution in high yields upon cooling, with no inclusion of the acid promoter or of phenanthroline. 2,6‐Dinitrotoluene can also be efficiently carbonylated to the corresponding dicarbamate.     

Hydrogenation of carbon dioxide on iron catalysts doubly promoted with manganese and potassium

The effect of addition of manganese and potassium promoters onto iron catalysts for hydrogenation of carbon dioxide was investigated. Catalyst characterizations were performed using BET surface area measurement, carbon monoxide chemisorption, temperature-programmed reduction and Mössbauer spectroscopy. It was noted that metallic iron catalysts were carburized to θ-Fe₃C and χ-Fe₅C₂ as well as oxidized to Fe₃O₄ during the course of reaction. The promotional effect of manganese was reflected in stabilization of catalytic behavior owing to a higher resistance to bulk oxidation. However, the distribution of hydrocarbon products did not change significantly in the presence of manganese promoter. With further addition of potassium promoter, the bulk phase was more likely to transform to carbides, and the selectivity toward olefins and long-chain hydrocarbons was remarkably enhanced.     

Reduction of Vegetable Oil-Derived Fatty Acid Methyl Esters toward Fatty Alcohols without the Supply of Gaseous H2

An alternative route to the conventional one for fatty alcohol synthesis was investigated. It was possible to synthesize lauryl alcohol from methyl laurate via reduction by transfer of hydrogen and hydride in liquid phase, in noncatalytic reactions and without the supply of H₂ gaseous. Pure NaBH₄ or alumina-supported NaBH₄ and methanol were used as co-reactants and 100% fatty alcohol selectivities were achieved. The aim of supporting the metal hydride was to increase its stability and achieve the full recovery of the solid at the end of reaction. When alumina-supported NaBH₄ was used, a final fatty alcohol yield of 93% was achieved. The use of methanol and NaBH₄ in amounts higher than stoichiometric is important to generate alkoxyborohydride anions which act as better reducing species than NaBH₄. The reaction conditions effect was investigated and the role of short carbon chain alcohol structure was elucidated. The effect of fatty acid methyl ester structure was also studied. Fatty acid methyl esters with shorter carbon chain length and without unsaturation (methyl laurate, methyl myristate) were easily reduced using NaBH₄/Al₂O₃ and methanol reaching high conversions and fatty alcohol selectivities. Unsaturated fatty acid methyl ester with longer carbon chain (methyl oleate) introduced steric hindrance which disfavoured interaction between ester and reducing solid surface and fatty acid methyl ester conversion was noticeably lower. A reaction mechanism based on alkoxyborohydride anions as the actual reducing species was proposed. This mechanism fully interprets results obtained during fatty acid methyl ester reduction using short carbon chain alcohols and metal hydride.     

Factors affecting the carbonylation of methanol over sulfided CoMo/C catalysts at atmospheric pressure

Methanol carbonylation has been carried out over carbon supported sulfided CoMo catalysts without addition of CH₃I, as promoter, to the feed. A temperature around 250°C, and methanol concentrations higher than 5 mol% were found to be optimum for ester production. Sulfided Mo/C catalysts were inactive for methanol carbonylation, methane being the major product. While sulfided Co/C catalysts were as effective for ester production as CoMo/C catalysts, methanol conversion was higher in the latter. The selectivity to methyl acetate was found to be strongly dependent on the nature of the carbon support.     

乙酸甲酯的合成与应用新进展

介绍了近几年国内外有关乙酸甲酯合成与应用的研究新进展，提出了甲醇脱氢合成法，并重点探讨和比较了反应精馏法和甲醇羰化法的合成研究，对发展乙酸甲酯工业具有指导意义。