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Disulphides, reactions

E. Jellum and S. Skrede, Biological aspects of thiol-disulphide reactions during treatment with penicillamine, iji "Penicillamine research in rheumatic disease", E. Munthe, ed., Fabritius/MSD, Oslo, (1977) p. 68. [Pg.380]

Further reaction then occurs between the disulphur dichloride and the carbon disulphide ... [Pg.196]

This was formerly manufactured by passing sulphur vapour over white hot coal or charcoal. An equilibrium was established and the carbon disulphide vapour was condensed, allowing the reaction to proceed ... [Pg.201]

The inflammable solvents most frequently used for reaction media, extraction or recrystallisation are diethyl ether, petroleum ether (b.p. 40-60° and higher ranges), carbon disulphide, acetone, methyl and ethyl alcohols, di-Mo-propyl ether, benzene, and toluene. Special precautions must be taken in handling these (and other equivalent) solvents if the danger of Are is to be more or less completely eliminated. It is advisable to have, if possible, a special bench in the laboratory devoted entirely to the recovery or distillation of these solvents no flames are permitted on this bench. [Pg.90]

Xanthates (or xanthogenates), t.g., CS(OR)SK, are formed by the reaction between carbon disulphide and an alcoholic solution of potassium hydroxide, for example ... [Pg.496]

In a 1 litre round-bottomed flask provided with an efficient double surface condenser, place 40 g. (39 ml.) of aniline, 50 g. (40 ml.) of carbon sulphide CAUTION inflammable) (1), and 50 g. (63-5 ml.) of absolute ethyl alcohol (2). Set up the apparatus in the fume cupboard or attach an absorption device to the top of the condenser (see Fig. 11, 8, 1) to absorb the hydrogen sulphide which is evolved. Heat upon an electrically-heated water bath or upon a steam bath for 8 hours or until the contents of the flask sohdify. When the reaction is complete, arrange the condenser for downward distillation (Fig. 11, 13, 3), and remove the excess of carbon disulphide and alcohol (CA UTION inflammable there must be no flame near the receiver). Shake the residue in the flask with excess of dilute hydrochloric acid (1 10) to remove any aniline present, filter at the pump, wash with water, and drain well. Dry in the steam oven. The yield of crude product, which is quite satisfactory for the preparation of phenyl iao-thiocyanute (Section IV.95), is 40-45 g. Recrystalhse the crude thiocarbanihde by dissolving it, under reflux, in boiling rectified spirit (filter through a hot water funnel if the solution is not clear), and add hot water until the solution just becomes cloudy and allow to cool. Pure sj/m.-diphenylthiourea separates in colourless needles, m.p, 154°,... [Pg.642]

The addition of powdered potassium hydroxide (about 20 per cent, of the weight of the carbon disulphide) reduces the refluxing period necessary to complete the reaction. [Pg.642]

To the cold acid chloride add 175 ml. of pure carbon disulphide, cool in ice, add 30 g, of powdered anhydrous aluminium chloride in one lot, and immediately attach a reflux condenser. When the evolution of hydrogen chloride ceases (about 5 minutes), slowly warm the mixture to the boiling point on a water bath. Reflux for 10 minutes with frequent shaking the reaction is then complete. Cool the reaction mixture to 0°, and decompose the aluminium complex by the cautious addition, with shaking, of 100 g. of crushed ice. Then add 25 ml. of concentrated hydrochloric acid, transfer to a 2 htre round-bottomed flask and steam distil, preferably in the apparatus, depicted in Fig. II, 41, 3 since the a-tetralone is only moderately volatile in steam. The carbon disulphide passes over first, then there is a definite break in the distillation, after whieh the a-tetralone distils completely in about 2 htres of distillate. [Pg.738]

The commercial product, m.p. 53-55°, may be used. Alternatively the methyl -naphthyl ketone may be prepared from naphthalene as described in Section IV,136. The Friedel - Crafts reaction in nitrobenzene solution yields about 90 per cent, of the p-ketone and 10 per cent, of the a-ketone in carbon disulphide solution at — 15°, the proportions ore 65 per cent, of the a- and 35 per cent, of the p-isomer. With chlorobenzene ns the reaction medium, a high proportion of the a-ketone is also formed. Separation of the liquid a-isomer from the solid p-isomer in Such mixtures (which remain liquid at the ordinary temp>erature) is readily effected through the picrates the picrate of the liquid a-aceto compound is less soluble and the higher melting. [Pg.767]

Reaction of alkali cellulose with carbon disulphide to produce a cellulose xanthate which forms a lyophilic sol with caustic soda. This may be extruded into a coagulating bath containing sulphate ions which hydrolyses the xanthate back to cellulose. This process is known as the viscose process and is that used in the manufacture of rayon. [Pg.633]

Industrially, chlorine is obtained as a by-product in the electrolytic conversion of salt to sodium hydroxide. Hazardous reactions have occuned between chlorine and a variety of chemicals including acetylene, alcohols, aluminium, ammonia, benzene, carbon disulphide, diethyl ether, diethyl zinc, fluorine, hydrocarbons, hydrogen, ferric chloride, metal hydrides, non-metals such as boron and phosphorus, rubber, and steel. [Pg.280]

During emulsion polymerization, a high conversion of monomer to polymer produces cross-linked rubber which is insoluble. To obtain a high conversion in the polymerization reaction and a processable polymer, suitable polymer modification should be made. The use of sulphur moieties allows this goal to be reached [2]. Sulphur-modified polychloroprenes contain di- and polysulphide sequences in the polymer chains. After the polymerization reaches the desired degree, reaction is stopped by adding thiuram disulphide ... [Pg.590]

The reaction of a-aminonitriles and carbon disulphide was stated by Cook and Heilbron to give 5-amino-2-mercaptothiazoles however, they later found that the same reaction with aminoacetonitrile was more complex. When aminoacetonitrile sulphate in ethanolic solution was treated with carbon disulphide, the dithiodicarbamate 9 was formed. Benzylation was then carried out treatment of the resulting ester 10 with phosphorus tribromide with subsequent loss of water gave 5-amino-2-benzylthiothiazole 11 in a quantitative fashion. The rapid reaction was thought to be the first example of the formation of a 5-aminothiazole from an a-aminoamide. [Pg.277]

All reactions involving the uniform formation and growth of a film of reaction product (e.g. reaction of metals with high-temperature water, reaction of copper with sulphur dissolved in carbon disulphide). [Pg.20]

Acetyl chloride (60 mmol) was added dropwise with stirring to an ice-cold mixture of 2-trimethylsilyltoluene (60 mmol) and aluminium trichloride (60mmol) in carbon disulphide (60 ml). Stirring was continued for 3h at 0-5 °C, and then the reaction mixture was poured on to ice-cold dilute HCI. [Pg.31]

To a cooled (2-8 °C) solution of A1C13 in carbon disulphide or nitrobenzene was added dropwise an equimolar mixture of the alkynylsilane and the acid chloride (or anhydride), dissolved in a little of the same solvent. After being stirred for 30 min, the reaction mixture was poured onto dilute sulphuric acid/ice. Normal isolation procedures gave the alkynone (50-90%). [Pg.118]

The acetylation reaction has been used by a number of workers for this purpose. Using acetyl chloride with aluminium chloride as catalyst in carbon disulphide or... [Pg.182]

Few racemic alkyl p-tolyl sulphoxides were prepared in rather low yields (16—40%) by the reaction of Grignard reagents with mixed anhydrides 108, 109 and compound HO formed in situ from p-toluenesulphinic acid and 3-phthalimidoxy-l,2-benzoisothiazole 1, 1-dioxide167 (equation 59). The mixed anhydrides 109 or 110 when reacted with cyclopen-tene and cyclohexene enamines 111 gave the corresponding a-ketocycloalkyl sulphoxides 112 in low yields (10-41%) along with small amounts of several by-products such as disulphides and thiosulphonates167 (equation 60). [Pg.261]


See other pages where Disulphides, reactions is mentioned: [Pg.319]    [Pg.349]    [Pg.219]    [Pg.11]    [Pg.319]    [Pg.349]    [Pg.219]    [Pg.11]    [Pg.10]    [Pg.28]    [Pg.258]    [Pg.587]    [Pg.676]    [Pg.725]    [Pg.733]    [Pg.962]    [Pg.107]    [Pg.553]    [Pg.278]    [Pg.418]    [Pg.178]    [Pg.145]    [Pg.171]    [Pg.173]    [Pg.282]   


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Carbon disulphide, reaction

Disulphide bonds exchange reactions

Disulphides

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Disulphides, reactions with alkynes

Reactions of Disulphides

Reactions of Disulphides and Polysulphides

Reactions, with disulphides

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