The reaction of carbon monoxide with platinum ylids

The platinum(II) ylids [X₂Pt{CH(py)CH₂CH₃}(py)] (X = Cl, Br; PY = pyridine) react with carbon monoxide to give the platinum carbonyls [CO(X₂)Pt{CH(py)CH₂CH₂CH₃}] which lose CO on heating or in solution. The platinum(IV) ylids [Cl₄Pt{CH(py)CH₂CH₃}(py)] and[Cl₂I(CH₃)Pt{CH(py)CH₂CH₃}(py)] also react with CO to give Pt(CO)-ylid compounds.     

Desulfurization of mercaptans to hydrocarbons by carbon monoxide and water in the presence of cobalt carbonyl

Benzylic mercaptans and thiophenols undergo desulfurization when exposed to carbon monoxide and water, with cobalt carbonyl as the catalyst; carbonyl sulfide is evolved in these reactions.     

The photochemically induced reaction of sulfur dioxide with alkanes and carbon monoxide

Abstract— The gas phase photochemical reactions of SO₂ induced by 3130 Å radiation have been studied in the presence of added alkanes or added CO. The quantum yields obtained in the reactions with the low molecular weight alkanes employed are lower than those obtained by previous workers. The quantum yields were found to be pressure dependent increasing slowly with increasing pressure. A stoichiometric ratio of one SO₂ removed per molecule of hydrocarbon consumed was observed only under experimental conditions of [SO₂] < [RH]. For reaction mixtures where [SO₂] < [RH] the ratio of [SO₂]/[RH] reacted always exceeded unity. The quantum yields decreased slightly with increasing temperature. In all the alkane reaction systems studied, the deposition of viscous, nonvolatile reaction products was observed. In the experiments with added CO, the quantum yields were computed with respect to the rate of CO₂ formation. At 25°C and equal pressures of SO₂ and CO, φco₂ was observed to be 0.005 and it decreased slightly with increasing temperature. The results obtained are interpreted in terms of the sulfoxidation of the alkanes and the oxidation of CO proceeding by way of a ³SO₂ reaction intermediate.     

Cobalt carbonyl catalysed reaction of oxetanes with a hydrosilane and carbon monoxide

The cobalt carbonyl catalyzed reaction of oxetanes with HSiR₃ and CO took place at 25°C under 1 atm to give not only 1,4-disiloxybutanes but also 1-siloxypropanes. The product ratio was highly dependent on the solvent used.     

A new insight into palladium-catalyzed reaction of 2-alkynylphenol with carbon monoxide

A novel and efficient pathway for the generation of 3-(benzofuran-3-ylmethylene)benzofuran-2(3H)-ones via a palladium-catalyzed carbonylative reaction of 2-alkynylphenol with carbon monoxide is described. The reaction proceeds through a double insertion of triple bonds during the reaction process. The products are obtained in good yields with high selectivity. A one-pot synthesis starting from 2-iodophenol and alkyne is presented as well.     

Effect of solvent properties on reaction of isocyanates with mercaptans

Generalization of data on the reaction rate of catalyzed process between mercaptans and phenyl isocyanate in various media led to the conclusion that the reaction rate increased due to the specific, especially nucleophilic, solvation. The primary reaction stage is the formation of a complex between the acidic mercaptan and a base, a catalyst (triethylamine) or basic solvent.     

Dichlorosilylene: Rate constant for reaction with carbon monoxide and nitrous oxide

The absolute rate constanss for the gas-phase reactions of 1,1-dichlorosilylene with carbon monoxide and nitrous oxide have been determined using the flash photolysts-kinetic absorpiton spectroscopy technique. The bimolecular rate constant values at 25° C are: $$\begin{gathered} k\left( {Cl_2 Si + CO} \right) = \left( {6.3 \pm 0.7} \right) \times 10^8 M^{ - 1} s^{ - 1} \hfill \\ k\left( {Cl_2 Si + N_2 O} \right) = \left( {5.7 \pm 0.3} \right) \times 10^8 M^{ - 1} s^{ - 1} \hfill \\ \end{gathered} $$      

Activity of silver catalysts in the reaction of nitric oxide with carbon monoxide

The specific catalytic activity of supported silver at equivalent amounts of reagents is approximately 10 times lower than that of silver powder. This is due to the influence of the reaction medium on the catalyst: under the reaction conditions, microcrystals of silver are extensively oxidized and lose their activity. In the steady state the reaction proceeds mainly on large silver crystallites, which remain in the metallic state under reaction conditions. At excess carbon monoxide, no significant influence of the metal dispersity on the catalytic activity is observed.

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Kinetics and mechanism of the reaction of tetracobalt dodecacarbonyl with carbon monoxide under pressure

The kinetics of the reaction of tetracobalt dodecacarbonyl with carbon monoxide to form dicobalt octacarbonyl in n-hexane have been investigated over a wide range of temperature and CO pressure. The reaction is first order in [Co₄(CO)₁₂]; the order in [CO] changes between one (at low pressures and high temperatures) and two (at high pressures and low temperatures).Activation parameters have been estimated and a mechanism involving initial reversible breaking of one CoCo bond, followed by irreversible breaking of a second, is proposed. The first step involves concerted addition of CO while the second can proceed with or without such addition.     

The source of the carbon monoxide in the classical Belousov-Zhabotinsky reaction

CO and CO2 evolution was measured in a cerium and in a ferroin-catalyzed Belousov-Zhabotinsky (BZ) reaction. These gases were stripped from the reaction mixture by a N2 carrier gas, mixed with H2, converted to methane on a Ni catalyst, and then measured by a flame ionization detector (FID). CO could be detected separately by absorbing CO2 on a soda lime column. In separate experiments it was proven that CO is produced in a reaction of BrO2* radicals with bromomalonic acid (BrMA). To this end BrO2(.-) radicals were generated in two different ways: (i) in the reaction HBrO2 + HBrO3 <--> 2 BrO2(.-) + H2O and (ii) by reducing HBrO3 to BrO2(.-) by Fe(2+). It was found that (.-)OH radicals--produced by Fenton's reagent--can also generate CO from BrMA. We propose that CO can be formed when an inorganic radical (like BrO2(.-) or (.-)OH) reacts with the enol form of BrMA producing an acyl radical which decarbonylates in the next step. Malonic acid (MA)-BrMA mixtures were prepared by a new method modifying Zaikin and Zhabotinsky's original recipe to minimize the production of dibromomalonic acid (Br2MA).     

Laser induced and controlled chemical reaction of carbon monoxide and hydrogen

Bimolecular chemical reaction control of gaseous CO and H(2) at room temperature and atmospheric pressure, without any catalyst, using shaped femtosecond laser pulses is presented. High intensity laser radiation applied to a reaction cell facilitates non-resonant bond breakage and the formation of a range of ions, which can then react to form new products. Stable reaction products are measured after irradiation of a reaction cell, using time of flight mass spectroscopy. Bond formation of C-O, C-C, and C-H bonds is demonstrated as CO(2)(+), C(2)H(2)(+), CH(+), and CH(3)(+) were observed in the time of flight mass spectrum of the product gas, analyzed after irradiation. The formation of CO(2) is shown to be dependent on laser intensity, irradiation time, and on the presence of H(2) in the reaction cell. Using negatively chirped laser pulses more C-O bond formation takes place as compared to more C-C bond formation for unchirped pulses.     

Synthesis and properties of copolymers of ethylene/carbon monoxide with styrene/carbon monoxide

The terpolymerization of ethylene, styrene, and carbon monoxide was accomplished by two different palladium‐based catalysts: a phosphine‐based ligand system and a nitrogen‐based ligand system. The range of possible compositions and the composition dependence of the properties of the resulting polymers were determined. These polymers were essentially carbon monoxide versions of the ethylene styrene interpolymers recently presented by Dow. A comparison between the two families of polymers is attempted. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 752–757, 2000