Carbon monoxide and methanol

Even though form amide was synthesized as early as 1863 by W. A. Hoffmann from ethyl formate [109-94-4] and ammonia, it only became accessible on a large scale, and thus iadustrially important, after development of high pressure production technology. In the 1990s, form amide is mainly manufactured either by direct synthesis from carbon monoxide and ammonia, or more importandy ia a two-stage process by reaction of methyl formate (from carbon monoxide and methanol) with ammonia. 

Similarly, nitroben2ene, carbon monoxide, and methanol can react sequentially in the presence of noble metal catalysts, to produce methyl A/-phenylcarbamate [2603-10-3] (4). The phenylcarbamate is subsequently coupled with formaldehyde [50-00-0] to yield the methylenebis(carbamate) (5) which is pyroly2ed to yield methylene diphenyl diisocyanate (MDI) (23). 

MMA from Propyne. Advances in catalytic carbonylation technology by Shell researchers have led to the development of a single-step process for producing MMA from propyne [74-99-7] (methyl acetylene), carbon monoxide, and methanol (76—82). 

This program helps calculate the rate of methanol formation in mol/m s at any specified temperature, and at different hydrogen, carbon monoxide and methanol concentrations. This simulates the working of a perfectly mixed CSTR specified at discharge condition, which is the same as these conditions are inside the reactor at steady-state operation. Corresponding feed compositions and volumetric rates can be calculated from simple material balances. 

Xs are surface fractions (or active centers), free and covered by chemisorbed species of hydrogen, carbon monoxide, and methanol. H, C, and M are activities of hydrogen, carbon monoxide, and methanol. Primes indicate equilibrium values. 

Discuss the range of values that the orders in hydrogen, carbon monoxide and methanol may assume if hydrogen adsorbs more weakly than the other gases. 

Gilman S. 1964. The mechanism of electrochemical oxidation of carbon monoxide and methanol on platinum. II. The reactant-pair mechanism for electrochemical oxidation of carbon monoxide and methanol. J Phys Chem 68 70-80. 

Lai SCS, LehedevaNP, Housmans THM, Koper MTM. 2007. Mechanisms of carbon monoxide and methanol oxidation at single-crystal electrodes. Top Catalysis 46 320-333. 

Kabbabi A, Faure R, Durand R, Beden B, Hahn F, Leger JM, Lamy C. 1998. In situ FTIRS study of the electrocatalytic oxidation of carbon monoxide and methanol at platinum-ruthenium bulk alloy electrodes. J Electroanal Chem 444 41-53. 

Knheiro ALN, Zei MS, Ertl G. 2005. Electro-oxidation of carbon monoxide and methanol on bate and Pt-modified Ru(10—10) electrodes. Phys Chem Chem Phys 7 1300. 

The darkness associated with dense interstellar clouds is caused by dust particles of size =0.1 microns, which are a common ingredient in interstellar and circum-stellar space, taking up perhaps 1% of the mass of interstellar clouds with a fractional number density of 10-12. These particles both scatter and absorb external visible and ultraviolet radiation from stars, protecting molecules in dense clouds from direct photodissociation via external starlight. They are rather less protective in the infrared, and are quite transparent in the microwave.6 The chemical nature of the dust particles is not easy to ascertain compared with the chemical nature of the interstellar gas broad spectral features in the infrared have been interpreted in terms of core-mantle particles, with the cores consisting of two populations, one of silicates and one of carbonaceous, possibly graphitic material. The mantles, which appear to be restricted to dense clouds, are probably a mixture of ices such as water, carbon monoxide, and methanol.7... 

Mechanistic Aspects of the Electrochemical Reduction of Carbon Monoxide and Methanol to Methane at Ruthenium and Copper Electrodes... 

The electrochemical reductions of carbon monoxide and methanol to methane (Equations 1 and 2) have potentials, under standard conditions, of +0.019 and +0.390 V vs SCE respectively (or a... 

Figure 2. Auger electron spectrum of the surface of two Ru electrodes after deactivation by reduction of carbon monoxide and methanol at higher temperatures (75 and 90 °C respectively in 0.2 M Na2SC>4 at pH 4 and -0.545 V vs SCE ). The presence of K on the surface must result from the adsorption of K+ ions present as an impurity in the electrolyte.

Tsuji and co-workers carbonylated a-carbonate-substituted allenes 113 with carbon monoxide and methanol, which provided 114 in excellent yields (Scheme 14.25) [54], They found that allenylic carbonates are more reactive than simple allylic carbonates and that the reaction proceeded rapidly even at ambient temperature under atmospheric pressure of carbon monoxide. Unfortunately, the poor E/Z selectivity diminishes the synthetic value of this very efficient carbonylation reaction. 

Following the first observations by Heck that Pd(OAc)2 can substitute a hydrogen atom in ethylene by a carbomethoxy group [50], Stille and James have discovered that the [Pd - Cu] couple catalyzes the incorporation of a COOMe group arising from carbon monoxide and methanol [51]. Most of the reactions with an alkene end up with a diester or a methoxyester, copper being used in stoichiometric quantities. Cyclic alkenes give preferentially diesters (Scheme 7). 

Pyrrolo-benzoxazepine 402 (Scheme 84, Section 5.2.1.1) gives ester 403 through the triflate intermediate by reaction with carbon monoxide and methanol in the presence of tetrakis(triphenylphosphine)palladium (1996JMC3435). 

One process that capitalizes on butadiene, synthesis gas, and methanol as raw materials is BASF s two-step hydrocarbonylation route to adipic acid(3-7). The butadiene in the C4 cut from an olefin plant steam cracker is transformed by a two-stage carbonylation with carbon monoxide and methanol into adipic acid dimethyl ester. Hydrolysis converts the diester into adipic acid. BASF is now engineering a 130 million pound per year commercial plant based on this technology(8,9). Technology drawbacks include a requirement for severe pressure (>4500 psig) in the first cobalt catalyzed carbonylation step and dimethyl adipate separation from branched diester isomers formed in the second carbonylation step. 

The speculative mechanism(20-21) as outlined in Equation 2 involves initial reaction between palladium(II) and butadiene to form a -complex 2 followed by a nucleophilic reaction with carbon monoxide and methanol to give 3. 

The treatment of the mercurio ketone with palladium (II) in the presence of carbon monoxide and methanol, Eq. (27) results in the formation of a y-keto ester with incorporation of one molecule of carbon monoxide [8], The overall conversion of a siloxycyclopropane to the keto ester may be performed without isolation of the mercurio ketone. 

Bromobenzocyclobutene 2 is converted to 4-benzocyclobutenyl carboxylic acid 3 by either of two routes (Fig. 2). The first method of preparation proceeds from the corresponding Grignard reagent of 2 followed by reaction with carbon dioxide [38], The acid 3 is obtained in a yield of 60-70%. The second method for the formation of 3 again starts with 4-bromobenzocyclobutene, but in this case 2 is reacted with a palladium zero catalyst in the presence of carbon monoxide and methanol to provide 4-carbomethoxybenzocyclobutene, 4 in a yield of > 95% [39, 40]. Ester 4 is hydrolyzed under standard conditions to provide 3 in an overall yield of 90% for the two steps [36]. 

In Ihe 1990s. formamide is mainly manufactured cither by direct synthesis from carbon monoxide and ammonia, or more importantly in a two-stage process by reaction of methyl formate (front carbon monoxide and methanol) with ammonia. 

Terminal monoalkenes were alkylated by stabilized carbanions (p a 10-18) in the presence of 1 equiv. of palladium chloride and 2 equiv. of triethylamine, at low temperatures (Scheme l).1 The resulting unstable hydride eliminate to give the alkene (path b), or treated with carbon monoxide and methanol to produce the ester (path c).2 As was the case with heteroatom nucleophiles, attack at the more substituted alkene position predominated, and internal alkenes underwent alkylation in much lower (=30%) yield. In the absence of triethylamine, the yields were very low (1-2%) and reduction of the metal by the carbanion became the major process. Presumably, the tertiary amine ligand prevented attack of the carbanion at the metal, directing it instead to the coordinated alkene. The regiochemistry (predominant attack at the more sub-... 

A methyl ester group is introduced, assembled f rom carbon monoxide and methanol. 

Terephthalic Acid from Toluene. Both carbon monoxide and methanol can react with toluene to yield intermediates that can be oxidized to terephthalic acid. In work conducted mainly by Mitsubishi Gas Chemical Company (62,63), toluene reacts with carbon monoxide and molar excesses of HF and BF3 to yield a jtanz-tolualdehyde—HF—BF3 complex. Decomposition of this complex under carefully controlled conditions recovers HF and BF3 for recycle and ra-tolualdehyde, which can be oxidized in place of para-xyiene to yield terephthalic acid. One drawback of the process is the energy-intensive, and therefore high cost, decomplexing step. The need for corrosion-resistant materials for construction and the need for extra design features to handle the relatively hazardous HF and BF3 also add to the cost. This process can be advantageous where toluene is available and xylenes are in short supply. 

Direct esterification of methacrylic acid with alcohols using sulfuric acid or other catalysts can be used to prepare methyl methacrylate (MMA) and other esters. Commercial routes for the direct preparation of MMA and some lower alkyl esters also exist. In the 1990s, researchers at Shell developed a direct route to MMA from propyne (methylacetylene), carbon monoxide, and methanol using a Pd(II) catalyst. The limited availability of propyne may slow the expansion of this highly efficient route to high purity MMA. Transesterification of MMA is often the preferred route for the preparation of other esters. 

Ans. In the homogeneous catalytic process for PO the by-product is f-butanol, which has an attractive market. The atom utilization by the old route for PO is 31%. The atom utilizations by the new route are 44 and 56% for PO and f-butanol. For methylmethacrylate the atom utilization by the new route (methyl acetylene plus carbon monoxide and methanol) is 100%, and by the old route is 46% (see R. A. Sheldon, Chemtech, 1994, March, 38-47). 

The rate of cobalt-catalyzed carbonylation is strongly dependent on both the pressure of carbon monoxide and methanol concentration. Complex 4.7, unlike 4.1, is an 18-electron nucleophile. This makes the attack on CH3I by 4.7 a comparatively slow reaction. High temperatures are required to achieve acceptable rates with the cobalt catalyst. This in turn necessitates high pressures of CO to stabilize 4.7 at high temperatures. 

Hydro(methoxycarbonyl)ation of epoxides has also been achieved this was accomplished by allowing the substrate to react with carbon monoxide and methanol at elevated pressures, at temperatures above 130, in the presence of cobalt salts or cobalt carbonyl as the catalyst. ... 

In order to prevent hydrogenolysis of the benzylidene group, Kalra substituted methanol in place of hydrogen other workers had previously shown that, by this modification of the oxo reaction, carbonyl insertion occurs in epoxides, with the formation of esters. - When the same substrate (75) was treated with carbon monoxide and methanol at 190 , the preponderant products were those formed by methanolysis and hydrolysis, with preponderant, tmns-diaxial opening of the epoxide, to give, in 30% yield, methyl 3-O-methyl-a-D-altropyranoside (78) and, in 26 % yield, methyl 4,6-O-benzylidene-a-D-altropyranoside (79). Part of the reaction product (15%) consisted of unchanged substrate, and there was evidence (from mass-spectral studies) that a carbonyl insertion had taken place to a very negligible extent (less than 5 %). 

As indicated in Section 11,4 (p. 64), direct treatment of alkyl halides with sodium cobalt tetracarbonyl, carbon monoxide, and methanol at elevated temperatures and pressures yields esters. Surprisingly, application of this reaction at 60° (using methanol instead of ether) to methyl tri-0-acetyl-2-deoxy-2-iodo-/3-D-glucopyranoside gave, almost exclusively, the elimination product (88) (in deacetylated form) and a compound presumed to be (on the basis of nuclear magnetic resonance evidence only) the branched-chain ester (87) in less than 0.5 % yield. It is thought that, in the presence of methanol, the sodium cobalt tetracarbonyl dissociates to yield sodium methoxide, and that this causes deacetylation of the substrate. 

The low-pressure acetic acid process was developed by Monsanto in the late 1960s and proved successful with commercialization of a plant producing 140 X 10 metric tons per year in 1970 at the Texas City (TX, USA) site [21]. The development of this technology occurred after the commercial implementation by BASF of the cobalt-catalyzed high-pressure methanol carbonylation process [22]. Both carbonylation processes were developed to utilize carbon monoxide and methanol as alternative raw materials, derived from synthesis gas, to compete with the ethylene-based acetaldehyde oxidation and saturated hydrocarbon oxidation processes (cf. Sections 2.4.1 and 2.8.1.1). Once the Monsanto process was commercialized, the cobalt-catalyzed process became noncom-... 

Eisenmann reported that in the presence of the catalyst and under conditions of the 0X0 reaction propylene oxide reacts with carbon monoxide and methanol to give methyl, 6-hydroxybutyrate in 40% yield. Later he found that the mtyor... 

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