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Benzoyl disulfide

It is convenient during this step to use the dropping funnel as an exhaust tube by attaching its upper end to a gas-absorption trap. If this is not done, the preparation should be conducted in a well-ventilated hood. [Pg.17]

The gas inlet tube should be of moderately large diameter or it may become plugged with crystals during the latter stages of the saturation with hydrogen sulfide. [Pg.17]

Stirring is discontinued after the benzoyl chloride has been added. The precipitate of potassium chloride can be separated more easily if the mixture is allowed to stand overnight before filtration. [Pg.17]

After the filtration and washing, the application of suction is continued imtU bubbles of hydrogen sulfide no longer form in the filtrate. Much of the excess hydrogen sulfide is removed during the filtration. [Pg.17]

The amount of iodine required is presumed to vary according to the presence of variable amounts of hydrogen sulfide and to the extent of oxidation by atmospheric oxygen. In one unsatisfactory preparation in which a relatively large amount of hydrogen sulfide must have remained in the solution a total of 493 g. (1.94 moles) of iodine was required and the final product contained free sulfur. [Pg.18]


Benzoyl suinde [644-32-6] M 174.4, m 131.2-132.3 . About 300mL of solvent was blown off from a filtered soln of benzoyl disulfide (25g) in acetone (350mL). The remaining acetone was decanted from the solid which was recrystd first from 300mL of 1 1 (v/v) EtOH/ethyl acetate, then from 300mL of EtOH, and finally from 240mL of 1 1 (v/v) EtOH/ethyl acetate. Yield about 40% [Pryor and Pickering J Am Chem Soc 84 2705 7962]. Handle in a fume cupboard because o/TOXICITY and obnoxious odour. [Pg.126]

Sulfhydryl compounds are oxidized with ease to disulfides. It is necessary to employ mild oxidizing agents that do not attack the product. Oxidation of an alkaline solution of n-amyl mercaptan by iodine is described for -amyl disulfide (68%). A mixed disulfide, ethyl /-butyl disulfide, is obtained in 63% yield by treatment of an equimolecular mixture of ethyl and /-butyl mercaptans with iodine in ethanol. Hydrogen peroxide is probably the best reagent for the oxidation. " Halo and amino groups in the molecule are unaffected. Benzoyl disulfide, CtHsCOSSCOCjH, is conveniently prepared by the iodine oxidation of the potassium salt of thiobenzoic acid, C4H5COSK. ... [Pg.850]

Sodium thiosulfate reacts with alkyl halides to form salts of the type RSSOjNa (Bunte salts). Alkyl disulfides may be obtained from these salts by pyrolysis or reaction with iodine or hydrogen peroxide. The yields range from 47% to 6S>%. Cyano and carboxyl groups do not interfere. Benzoylation of sodium thiosulfate produces benzoyl disulfide in 58% yield. ... [Pg.850]

In the seccHid part, surveys concerning telechelk telomers ate mentioned. The different telc ens used and their known transfer-constants are supplied alijAatic and aromatic disulfides, disubstituted benzoyl disulfides, functional xanthogens and polyhalogenated compounds. Also novel monoaddition reactions of functional monomers onto both end groups of dithiols and ditrichloromethyl compounds are summarized. [Pg.69]

Table 13. Transfer constants to the MMA of substituted benzoyl disulfides at 60 °C (according to Tsuda and Otsu) [88]... Table 13. Transfer constants to the MMA of substituted benzoyl disulfides at 60 °C (according to Tsuda and Otsu) [88]...
Table 14. Transfer constants to the styrene of substituted benzoyl disulfides... Table 14. Transfer constants to the styrene of substituted benzoyl disulfides...
This operation is carried out at room temperature because heating in the presence of alkalies decomposes benzoyl disulfide. [Pg.18]

Benzoyl disulfide has been obtained by the reaction of benzoyl chloride with hydrogen sulfide, hydrogen disulfide, hydrogen trisulfide, potassium sulfide, sodium disulfide, lead sulfide, sodium hydrosulfite, sodium thiosulfate, sulfhydrylmagnesium bromide, and thiobenzamide. It is also formed by reaction of benzoic anhydride with hydrogen sulfide. The better preparative methods involve the oxidation of thiobenzoic add by means of air,hydrogen peroxide or sulfur monochloride, or of the sodium or potassium salt by means of air, - chlorine, iodine, copper sulfate, - potassium ferricyanide, - or ferric chloride. - ... [Pg.18]

Benzoyl chloride dropped with stirring below 15° into abs. ethanol containing KHS, filtered, the filtrate cooled to 10-15 , and solid iodine added slowly with constant agitation, until a slight excess is present -> benzoyl disulfide. Y 68-73%. (R. L. Frank and J. R. Blegen, Org. Synth. 28, 16 (1948).)... [Pg.173]

Acyl and aroyl disulfides react by a somewhat different route. Both acetyl disulfide (225) and benzoyl disulfide (125) react exothermically with triethyl phosphite at room temperature to produce 0,0,0-triethyl phosphorothioate and the acyl or aroyl sulfide. This result suggests that the acyl-sulfur linkage in the phosphonium intermediate is more susceptible to cleavage by mercaptide ion than is the alkyl-oxygen bond. [Pg.84]

Benzoyl disulfide (dibenzoyl disulfide) [644-32-6] M 174.4, m 131.2-132.3". About 300ml of solvent is... [Pg.278]


See other pages where Benzoyl disulfide is mentioned: [Pg.128]    [Pg.851]    [Pg.16]    [Pg.17]    [Pg.9]    [Pg.9]    [Pg.72]    [Pg.262]    [Pg.254]    [Pg.278]    [Pg.241]    [Pg.291]    [Pg.699]    [Pg.279]    [Pg.290]    [Pg.698]    [Pg.254]    [Pg.186]    [Pg.188]   
See also in sourсe #XX -- [ Pg.16 , Pg.28 ]

See also in sourсe #XX -- [ Pg.16 , Pg.28 ]

See also in sourсe #XX -- [ Pg.16 , Pg.28 ]

See also in sourсe #XX -- [ Pg.16 , Pg.28 ]




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