Acetylenic sulfides, oxidation

Mahyisulfonyl chloride CH3SO2CI and tosyl chloride give low to moderate yields of ROCSO2CH3 and RC=CS02-Aryl. Part of the sulfonyl chloride reacts with the lithium alkynylide to give a chloroalkyne. A more succesful method to prepare acetylenic sulfones involves Oxidation of acetylene sulfides with peiacids. 

Ether solutions of magnesium cuprates undergo 1,4-additions to acetylenic phosphine oxides or sulfides, unlike organolithium reagents... 

Dalsgaard T. and Bak F. (1992) Effect of acetylene on nitrous oxide reduction and sulfide oxidation in batch and gradient cultures of Thiobacillus denitrificans. Appl. Environ. Microbiol. 58, 1601-1608. 

For example, carbon dioxide from air or ethene nitrogen oxides from nitrogen methanol from diethyl ether. In general, carbon dioxide, carbon monoxide, ammonia, hydrogen sulfide, mercaptans, ethane, ethene, acetylene (ethyne), propane and propylene are readily removed at 25°. In mixtures of gases, the more polar ones are preferentially adsorbed). 

Nickel peroxide is a solid, insoluble oxidant prepared by reaction of nickel (II) salts with hypochlorite or ozone in aqueous alkaline solution. This reagent when used in nonpolar medium is similar to, but more reactive than, activated manganese dioxide in selectively oxidizing allylic or acetylenic alcohols. It also reacts rapidly with amines, phenols, hydrazones and sulfides so that selective oxidation of allylic alcohols in the presence of these functionalities may not be possible. In basic media the oxidizing power of nickel peroxide is increased and saturated primary alcohols can be oxidized directly to carboxylic acids. In the presence of ammonia at —20°, primary allylic alcohols give amides while at elevated temperatures nitriles are formed. At elevated temperatures efficient cleavage of a-glycols, a-ketols... 

Cobalt Copper Acetylene, hydrazinium nitrate, oxidants Acetylene and alkynes, ammonium nitrate, azides, bromates, chlorates, iodates, chlorine, ethylene oxide, fluorine, peroxides, hydrogen sulfide, hydrazinium nitrate... 

Pericas and Jeong demonstrated independently that sulfur-tethered substrates, when subjected to the PKR conditions, afforded the desired bicyclic products. The sulfur tether is removed cleanly by Pummerer reaction after oxidation of sulfur to sulfoxide or 1,4-addition of bisalkyl cuprate followed by hydrogenolysis of sulfide with Raney nickel. It is worth mentioning that the regioselectivity regarding the acetylene part is opposite to that of the intermolecular version (Equation (30)). 

A second major type of reactor involves thermal destruction of the calcium carbide. At about 1,S00°F, both calcium carbide and acetylene are thermally oxidized. Therefore, a system such as a rotary kiln could be used for thermal destruction of the reactivity characteristics. The additional benefit of thermal destruction is that it will also effectively deal with potential sulfide reactivity problems. Large chunks of metals often included in the desulfurization slag will tend to be a problem for many types of thermal units. Concern over air emissions and cost are other hurdles to the use of thermal systems for calcium carbide desulfurization slag. 

The best-known gas hydrates are those of ethane, ethylene, propane, and isobulaue. Others include methane and I butene, most of the fluorocarbon refrigerant gases, nitrous oxide, acetylene, vinyl chloride, carbon dioxide, methyl and ethyl chloride, methyl and ethyl bromide, cyclopropane, hydrogen sulfide, methyl mercaptan, and sulfur dioxide. 

Organic constituents that may be found in ppb levels in WP/F smoke include methane, ethylene, carbonyl sulfide, acetylene, 1,4-dicyanobenzene, 1,3-dicyanobenzene, 1,2-dicyanobenzene, acetonitrile, and acrylonitrile (Tolle et al. 1988). Since white phosphorus contains boron, silicon, calcium, aluminum, iron, and arsenic in excess of 10 ppm as impurities (Berkowitz et al. 1981), WP/F smoke also contains these elements and possibly their oxidation products. The physical properties of a few major compounds that may be important for determining the fate of WP/F smoke in the environment are given in Table 3-3. 

Bauerle and co-workers have synthesized a macrocycle consisting of 8 thiophenes in conjugation by an oxidatively induced elimination of platinum complexes <03CC948>. The platinum complexes 55 were obtained by reaction of terthiophene with terminal acetylenic groups with cw-Pt(dppp)Cl2 in the presence of Cul and EtsN. C-C bond formation was effected by oxidatively induced elimination using iodine and the diacetylene bridged thiophene macrocycle 56 was converted to an all thiophene macrocycle 57 by reacting with sodium sulfide. 

A powerful oxidizer. Explosive reaction with acetaldehyde, acetic acid + heat, acetic anhydride + heat, benzaldehyde, benzene, benzylthylaniUne, butyraldehyde, 1,3-dimethylhexahydropyrimidone, diethyl ether, ethylacetate, isopropylacetate, methyl dioxane, pelargonic acid, pentyl acetate, phosphoms + heat, propionaldehyde, and other organic materials or solvents. Forms a friction- and heat-sensitive explosive mixture with potassium hexacyanoferrate. Ignites on contact with alcohols, acetic anhydride + tetrahydronaphthalene, acetone, butanol, chromium(II) sulfide, cyclohexanol, dimethyl formamide, ethanol, ethylene glycol, methanol, 2-propanol, pyridine. Violent reaction with acetic anhydride + 3-methylphenol (above 75°C), acetylene, bromine pentafluoride, glycerol, hexamethylphosphoramide, peroxyformic acid, selenium, sodium amide. Incandescent reaction with alkali metals (e.g., sodium, potassium), ammonia, arsenic, butyric acid (above 100°C), chlorine trifluoride, hydrogen sulfide + heat, sodium + heat, and sulfur. Incompatible with N,N-dimethylformamide. 

These methods suggested in the present form by Caunt83) rely on inhibition (retardation) effects of strong catalyst poisons on polymerization. Typical poisons potentially usable for this purpose are carbon oxides, carbonyl sulfide, carbon disulfide, acetylenes and dienes. All these substances exhibit a strong unsaturation they have either two double bonds or one triple bond. Most of the works devoted to application of the poisons to determination of active centers 10,63 83 102 1O7) confirm a complicated nature of their interaction with the catalytic systems. To determine the active centers correctly, it is necessary to recognize and — as much as practicable — suppress side processes, such as physical adsorption and chemisorption on non-propagative species, interaction with a cocatalyst, oligomerization and homopolymerization of the poison and its copolymerization with the main chain monomer. 

As already mentioned, vinyl sulfides are electron-rich dienophiles and react, therefore, preferentially with electron-poor dienes, i.e. in inverse-electron-demand processes such as those depicted in Scheme The auxiliary sulfur substituent may be removed at some stage after the cycloaddition, either by hydrogenolysis (e.g. -+ 81) or oxidation/sulfenic acid elimination (e.g. - 84), illustrating the potential of vinyl sulfides as ethylene or acetylene equivalents. 

Indirect methods used to estimate DNF include the acetylene block method (S0rensen, 1978), metabolite stoichiometry (Dollar et al., 1991), or stable isotope tracers (Nielsen, 1992). Acetylene (C2H2) blocks the terminal step of DNF, the conversion of N2O to N2, and the DNF rate is estimated by quantifying the production of N2O on a gas chromatograph with an electron capture detector. Problems with the acetylene block technique include blockage of NTR (which means that rates of coupled NTR—DNF cannot be obtained), inefficacy at low N03 concentration, and interference by H2S. Sulfide appears to alleviate the acetylene block of nitrous oxide reductase and permit full reduction of N2O to N2. 

In the presence of hydrogen chloride, a-acetylenic ketones react with thioacetic acid to give a monothio-)S-diketone which is converted to a 1,2-dithiolium ion by phosphorus pentasulfide or hydrogen sulfide. These reactions, which involve some sort of oxidation, are discussed in the next paragraph. 

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