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Carbon disulfide, reduction

Diethanolamine (DEA) has replaced MEA as the most widely used amine solvent. High load DEA technologies, such as that developed by Elf Aquitaine, permit the use of high (up to 40 wt % DEA) concentration solutions. The Elf Aquitaine—DEA process allows lower cinculation rates, and has consequent reductions ia capital and utility expenses. DEA tends to be more resistant to degradation by carbonyl sulfide and carbon disulfide than MEA. DEA is, however, susceptible to degradation by carbon dioxide. [Pg.211]

Tungsten pentachlofide [13470-13-8], WCl, mp 243°C, bp 275.6°C, is a black, crystalline, deHquescent soHd. It is only slightly soluble in carbon disulfide and decomposes in water to the blue oxide, 200 2. Magnetic properties suggest that tungsten pentachlofide may contain trinuclear clusters in the soHd state, but this stmcture has not been defined. Tungsten pentachlofide may be prepared by the reduction of the hexachloride with red phosphoms (9). [Pg.287]

Thiophosgene has been prepared in small yield by the chlorination of carbon disulfide in the presence of iodine and by the reduction of thiocarbonyl perchloride. ... [Pg.91]

Treatment of the heterocycle, 38 (obtained from ethylene-diamine and carbon disulfide), with nitrous acid affords the N-nitroso compound, 39. Reduction with zinc leads to the corre-... [Pg.230]

N204 also forms expl mixts with incompletely halogenated hydrocarbons, NGu, carbon disulfide, etc (Ref 33). The effect of spontaneous decompn by oxidation-reduction reactions when N204 is mixed with a number of fuels (hydrazine, gasoline, liq paraffin, etc) has resulted in its extensive use in liq propint rocket engines (Refs 12, 22, 27 35)... [Pg.314]

Attempts to follow a published procedure for the preparation of 1,3 -dithiole-2-thione-4,5-dithiolate salts [1], involving reductive coupling of carbon disulfide with alkali metals, have led to violent explosions with potassium metal, but not with sodium [2], However, mixtures of carbon disulfide with potassium-sodium alloy, potassium, sodium, or lithium are capable of detonation by shock, though not by heating. The explosive power decreases in the order given above, and the first mixture is more shock-sensitive than mercury fulminate [3],... [Pg.223]

Titanium (IV) iodide may be prepared by a variety of methods. High-temperature methods include reaction of titanium metal with iodine vapor,1-3 titanium carbide with iodine,4 titanium(IV) oxide with aluminum (III) iodide,5 and titanium (IV) chloride with a mixture of hydrogen and iodine. At lower temperatures, titanium (IV) iodide has been obtained by the combination of titanium and iodine in refluxing carbon tetrachloride7 and in hot benzene or carbon disulfide 8 a titanium-aluminum alloy may be used in place of titanium metal.9 It has been reported that iodine combines directly with titanium at room temperature if the metal is prepared by sodium reduction of titanium (IV) chloride and is heated to a high temperature before iodine is... [Pg.11]

The present procedure, which is based on those of Schumaker8 and Larsen and Lenoir,14 is simple and avoids the use of the troublesome and sometimes hazardous reduction of carbon disulfide with alkali metals. On several occasions a violent explosion has occurred in our laboratories during this reaction. [Pg.136]

Carbon is able to bind sulfur to its surface. The reaction of sugar charcoal or wood charcoal with elementary sulfur at temperatures of 400-1000° was studied in detail by Wibaut (118-122). In this reaction some carbon disulfide was formed as well as hydrogen sulfide, if hydrogen was present in the samples. The solid reaction products contained considerable amounts of sulfur, up to 20% by weight. The maximum sulfur uptake was observed at 600°. The sulfur was not completely volatized even by heating in a vacuum to 1000° (122). The sulfur came off in elementary form and as carbon disulfide. Neither could the sulfur be removed from the samples by extraction. It was disposed of by powerful chemical attack, e.g., by oxidation or by reduction with hydrogen at 700°. The formation of hydrogen sulfide started at 460°. [Pg.211]

Soil In both soils and water, chemical and biological mediated reactions can transform thiram to compounds containing the mercaptan group (Alexander, 1981). Decomposes in soils to carbon disulfide and dimethylamine (Sisler and Cox, 1954 Kaars Sijpesteijn et al., 1977). When a spodosol (pH 3.8) pretreated with thiram was incubated for 24 d at 30 °C and relative humidity of 60 to 90%, dimethylamine formed as the major product. Minor degradative products included nitrite ions (nitration reduction) and dimethylnitrosamine (Ayanaba et al., 1973). [Pg.1051]

Cagniant and Cagniant have reported that succinoylation of benzo[6]thiophene under Friedel-Crafts conditions yields a separable mixture of the y-ketobutyric acids 42a and 43a in a ratio of 9 1 (combined yield 85%). Huang-Minlon reduction of 42a to the butyric acid (90%) followed by cyclization of the derived acid chloride (90%) was reported to yield 4-keto-l,2,3,4-tetrahydrodibenzothiophene (44a) (69% overall). Likewise, acylation of benzo[6]thiophene with the ester chloride of succinic acid in carbon disulfide-aluminum chloride gave a separable mixture (80%) of the 2- and 3-y-ketobutyric esters. Two alternative... [Pg.231]

Acyloins were converted to mixtures of stereoisomeric vicinal diols by catalytic hydrogenation over copper chromite [972]. More frequently they were reduced to ketones by zinc (yield 77%) [913, 914], by zinc amalgam (yields 50-60%) [975], by tin (yields 86-92%) [173], or by hydriodic acid by refluxing with 47% hydriodic acid in glacial acetic acid (yields 70-90%) [916], or by treatment with red phosphorus and iodine in carbon disulfide at room temperature (yields 80-90%) [917] Procedure 41, p. 215). Since acyloins are readily accessible by reductive condensation of esters (p. 152) the above reductions provide a very good route to ketones and the best route to macro-cyclic ketones [973]. [Pg.125]

Electrolytic reduction of H SO /HjSeO mixtures using aluminium electrodes results in the formation of a sulfur-selenium coating at the elwtrode Irradiation of a solution of SCg in carbon disulfide by sunhght for 1-2 hours at 20 °C results in the formation of various cyclic selenium sulfides The formation of Se Sg compounds is also initiated by refluxing the above solution . ... [Pg.184]

Benzofuranyl)butanoic acid readily forms the acid chloride, and this undergoes intramolecular Friedel-Crafts acylation on treatment with tin(IV) chloride in carbon disulfide at room temperature, providing 1,2,3,4-tetra-hydro-l-dibenzofuranone (54%). " This intermediate has been converted to dibenzofuran by lithium aluminum hydride reduction and subsequent dehydrogenation, to 1-methyldibenzofuran by Grignard reaction and dehydrogenation, and to 1-dibenzofuranol by reaction with iV-bromosuccinimide and subsequent dehydrobromination with pyridine. [Pg.33]

Late in the nineteenth century, Herman Sprengel patented a series of simple oxidation-reduction mixts for use in commercial blasting. These so-called Sprengel explosives typically consisted of coned nitric acid, or liquid N02, mixed with liq fuels such as nitrobenzene, carbon disulfide, petroleum, etc. They were intended to be mixed immediately before use. Because of handling difficulties Sprengel expls never became very popular (Refs 4 6)... [Pg.584]

Compound I may be prepared by the reduction of carbon disulfide either electrochemically6 or by use of an alkali metal.7 In this report we present the synthesis of BEDT-TTF, and derivatives, via the procedure just described beginning with the alkali metal reduction of carbon disulfide. In our hands we find this procedure easier to set up and use than that involving the electrolytic reduction of carbon disulfide. [Pg.387]

Reductive amination of benzaldehyde with (R)-81 provided the corresponding benzyl amine, which was reductively alkylated with formaldehyde to give 82 (Scheme H) " Compound 82 was debenzylated by hydrogenation in the presence of Pearlman s catalyst to afford frovatriptan ((/J)-6). Alternatively, monomethylation of amine (/ )-81 was affected by treatment with carbon disulfide and dicyclohexylcarbodiimide in pyridine to provide isothiocyanate 83, which was reduced with sodium borohydride to give (l )-6. [Pg.182]

Larger runs, up to 5.4 moles of carbon disulfide, have been made with only a slight reduction in yield. [Pg.82]

In this review we have attempted to cover the very recent literature relevant to the coordination chemistry of carbon dioxide and its use as a source of chemical carbon. We have omitted similar investigations involving the more reactive substrates, carbon disulfide and carbonyl sulfide. The reader is referred to a recent review by Ibers (722) which has contrasted the behavior of these sulfides to carbon dioxide. Likewise we have, as stated at the onset, elected to neglect heterogeneous processes involving the reduction... [Pg.163]


See other pages where Carbon disulfide, reduction is mentioned: [Pg.326]    [Pg.122]    [Pg.116]    [Pg.243]    [Pg.777]    [Pg.66]    [Pg.9]    [Pg.4]    [Pg.29]    [Pg.149]    [Pg.136]    [Pg.122]    [Pg.262]    [Pg.171]    [Pg.732]    [Pg.365]    [Pg.326]    [Pg.384]    [Pg.144]    [Pg.207]    [Pg.595]    [Pg.88]    [Pg.116]    [Pg.299]    [Pg.383]    [Pg.187]   
See also in sourсe #XX -- [ Pg.679 ]




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