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Sulfides from alcohols

Vinyllithium [917-57-7] can be formed direcdy from vinyl chloride by means of a lithium [7439-93-2] dispersion containing 2 wt % sodium [7440-23-5] at 0—10°C. This compound is a reactive intermediate for the formation of vinyl alcohols from aldehydes, vinyl ketones from organic acids, vinyl sulfides from disulfides, and monosubstituted alkenes from organic halides. It can also be converted to vinylcopper [37616-22-1] or divinylcopper lithium [22903-99-7], which can then be used to introduce a vinyl group stereoselectively into a variety of a, P-unsaturated systems (26), or simply add a vinyl group to other a, P-unsaturated compounds to give y, 5-unsaturated compounds. Vinyllithium reagents can also be converted to secondary alcohols with trialkylb o r ane s. [Pg.414]

Vinyl chloride reacts with sulfides, thiols, alcohols, and oximes in basic media. Reaction with hydrated sodium sulfide [1313-82-2] in a mixture of dimethyl sulfoxide [67-68-5] (DMSO) and potassium hydroxide [1310-58-3], KOH, yields divinyl sulfide [627-51-0] and sulfur-containing heterocycles (27). Various vinyl sulfides can be obtained by reacting vinyl chloride with thiols in the presence of base (28). Vinyl ethers are produced in similar fashion, from the reaction of vinyl chloride with alcohols in the presence of a strong base (29,30). A variety of pyrroles and indoles have also been prepared by reacting vinyl chloride with different ketoximes or oximes in a mixture of DMSO and KOH (31). [Pg.414]

When reactions with oxygen-containing acceptors were performed [3] in the 300-400°C region, the formation of adducts occurred with both Tetralin and mesitylene. This reaction was observed when benzyl radicals were generated from dibenzyl ether, dibenzyl sulfide, benzyl alcohol, and benzaldehyde. [Pg.378]

A number of mechanistic pathways have been identified for the oxidation, such as O-atom transfer to sulfides, electrophilic attack on phenols, hydride transfer from alcohols, and proton-coupled electron transfer from hydroquinone. Some kinetic studies indicate that the rate-determining step involves preassociation of the substrate with the catalyst.507,508 The electrocatalytic properties of polypyridyl oxo-ruthenium complexes have been also applied with success to DNA cleavage509,5 and sugar oxidation.511... [Pg.499]

The method described is adapted from the procedures of Kym 3 and Engelhardt, Latschinoff, and Malyscheff.4 Thio-benzoic acid has been prepared by the reaction of benzoyl chloride with potassium sulfide,4 hydrogen sulfide in pyridine,6 6 and magnesium bromide hydrosulfide.7 It is formed from dibenzoyl disulfide with potassium hydrosulfide,4 potassium hydroxide,4 8 and ammonia.9 It is also formed from dibenzoyl sulfide, from phenyl benzoate, and from benzoic anhydride with alcoholic potassium hydrosulfide.4 It has been obtained from dibenzoyl sulfide and hydrogen sulfide,10 carbon oxysulfide and phenyl-magnesium bromide,11 12 dibenzyl disulfide and sodium ethoxide,13 benzyl chloride and sulfur in the presence of potassium hydroxide,14 and benzylthiosulfuric acid and alkali.18 16... [Pg.103]

Efficient procedures for the direct preparation of allyl sulfides from allylic alcohols have also been reported [21]. [Pg.10]

Sulfides can be prepared from alcohols. A convenient conversion under mild conditions and in high yields has been published [20], The work-up is particularly simple. [Pg.117]

More recently, chemiluminescence detectors based on redox reactions have made possible the detection of many classes of compounds not detected by flame ionization. In the redox chemiluminescence detector (RCD), the effluent from the column is mixed with nitrogen dioxide and passed across a catalyst containing elemental gold at 200-400°C. Responsive compounds reduce the nitrogen dioxide to nitric oxide. The nitric oxide is reacted with ozone to give the chemiluminescent emission. The RCD yields a response from compounds capable of undergoing dehydrogenation or oxidation and produces sensitive emissions from alcohols, aldehydes, ketones, acids, amines, olifins, aromatic compounds, sulfides, and thiols. [Pg.54]

Fig. 17.13. Mechanism of the Swern oxidation of alcohols. The actual reagent is an "activated DMSO" (compound B or D), which reacts with an alcohol with formation of A or C, respectively. Dissociation leads to the sulfonium salt E, which is then converted into the sulfonium ylide F after NEt3 addition and raising the temperature from -60 to -45 °C. /3-Elimination via a cyclic transition state generates the carbonyl compound and dimethyl sulfide from F. Fig. 17.13. Mechanism of the Swern oxidation of alcohols. The actual reagent is an "activated DMSO" (compound B or D), which reacts with an alcohol with formation of A or C, respectively. Dissociation leads to the sulfonium salt E, which is then converted into the sulfonium ylide F after NEt3 addition and raising the temperature from -60 to -45 °C. /3-Elimination via a cyclic transition state generates the carbonyl compound and dimethyl sulfide from F.
Bromothiazole (1) reacts with thiourea in alcohol to yield a mixture of dithiazolyl monosulfide (2) and A-4-thiazoline-2-thione (3) (Scheme 1) (4-6). Treatment of 2-bromo-4-methvlthiazole with potassium hydrogen sulfide in alcohol is reported to result in the formation of bis(4-methyl-2-thiazolylisulfide (7). which probably results from the reaction between the initially formed 2-mercaptothiazole and the initial 2-bromo-4-methylthiazole. [Pg.192]

Some of the radicals derived from alcohols, ethers, ketones, nitriles, and sulfides are given in Tables 6, 7, and 8. [Pg.69]

Symmetrical sulfides are obtained in 70-90% yields by refluxing aqueous alcoholic solutions of halides with sodium sulfide. The nonahydrate of sodiiun sulfide is a satisfactory reagent for the reac-tion. Tetramethylene and pentamethylene halides give cyclic sulfides, e.g., tetramethylene sulfide (tetrahydrothiophene) (64%). Halides containing several other important functional groups have been employed. Typical examples include methallyl chloride, and halides with hydroxyl, ethoxyl, carboxyl, and diethylamino groups in the beta position. A dry synthesis of phenyl sulfide from calcium oxide, sulfur, and chlorobenzene at 300° has been reported. ... [Pg.399]

A novel tandem process has been reported " for the preparation of allylic amines, ethers, and sulfides from a-bromo-a, jS-unsaturated sulfones. The process is believed to proceed via an initial conjugate addition followed by proton exchange and Ramberg-Backlund rearrangement (see Scheme 75). A new variant of the Ramberg-Backlund reaction has been described in which a, /f-epoxy sulfones (319), on treatment with base, are converted into a range of mono-, di-, and tri-substituted allylic alcohols (320). [Pg.546]

Thiols have also been prepared from alcohols. One method involves treatment with H2S and a catalyst, such as Al203, but this is limited to primary alcohols. Another method involves treatment with Lawesson s reagent (see 16-10). When epoxides are substrates, the products are (3-hydroxy thiols. Tertiary nitro compounds give thiols (RNO2 —> RSH) when treated with sulfur and sodium sulfide, followed by amalgamated aluminum. ... [Pg.549]

Manufacture of dithiophosphoric ester acids from alcohol.s and diphosphorus(V) sulfide... [Pg.94]


See other pages where Sulfides from alcohols is mentioned: [Pg.685]    [Pg.516]    [Pg.368]    [Pg.685]    [Pg.1317]    [Pg.33]    [Pg.888]    [Pg.1331]    [Pg.813]    [Pg.692]    [Pg.1683]    [Pg.187]    [Pg.190]    [Pg.546]    [Pg.546]    [Pg.72]    [Pg.414]    [Pg.100]    [Pg.178]    [Pg.431]    [Pg.67]    [Pg.412]    [Pg.390]    [Pg.368]   
See also in sourсe #XX -- [ Pg.646 ]




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