Dimercaptan

Unusual reactions occur between diazomethane and heterocyclic thiocarbonyl compounds. For example, pyran-4-thiones give methylene ethers of 1,2-dimercaptans formed by dimerization (cf. 115 —>116). 4-Thioflavones and 4-thiochromones react similarly. 

Trimethylene dibromide, dl21 Trimethylene dimercaptan, pi95 Trimethylene glycol, pi92 Trimethylethylene, ml66 Trimethylgermanium bromide, b437... 

Following the preparation of 2,6-di(bromomethyl)triquinacene 471), dimercaptan 472 was synthesize conventionally. Coupling of these intermeiates produced a 3.5 to 1 mixture of anti- and syn-triquinacenophanes 473 and 474. These [somers were separate chromatographically and identities established by x-ray structure determination of 473... 

Recently, new types of organic positives, formed by a mixture of dimercaptan with polyaniline, have been reported. These composite materials appear to have an energy density higher than that of most inorganic intercalation oxides and good cyclability. However, use of these materials in practical rechargeable lithium batteries has still to be confirmed. 

Figure 1.3.2 a,u-Dimercaptans with Tm plotted against Nc. (Source Reprinted with permission from Ref. 19. Copyright (1943) American Chemical Society.)... 

Although the compounds in which R" is alkyl can be prepared more readily by the simple Mannich reaction, this sequence is useful for nitrogen compounds such as aromatic amines, hydrazines, and hydroxylamine which do not ordinarily enter into the Mannich reaction. These intermediates react cleanly with mercaptans (21) and with dimercaptans (17) to produce compounds of the type XVI and XVII. 

Reaction with mercaptans and dimercaptans (12, 16, 21) proceeds normally to produce the 2-hydroxybenzyl thioether compounds XXV and XXVI. 

Of all the compounds prepared in this work, these latter compounds, the ortho-linked compounds derived from dimercaptans, come the closest to realizing our objective of structures with the activity of a bisphenol and the nondiscoloring characteristics of a monocyclic phenol. For example, Table IV shows some results in cw-polybutadiene which demonstrate that a compound of the type XXVI is superior as a heat stabilizer to both 2,6-di-terf-butyl-4-methylphenol and 2,2 -methylenebis(4-methyl-6-ferf-butylphenol) in both activity and color. Screening results in cis-... 

SYNS 1,2-DLMERCAPTOETHANE D DITHIOETHYL-ENEGLYCOL DITHIOGLYCOL ETHYLENE DIMERCAPTAN a-ETHYLENE DIMERCAPTAN ETHYLENE DITHIOGLYCOL ETHYLENEDITHIOL ETHYL HYDROPERSULFIDE... 

ETHYLENE DIHYDRATE see EJC500 ETHYLENE DIMERCAPTAN see EEBOOO a-ETHYLENE DIMERCAPTAN see EEBOOO ETHYLENE DIMETHYL ETHER see DOE600 ETHYLENE DINITRATE see EJGOOO ETHYLENEDINITRILOTETRAACETIC ACID see EIXOOO... 

The reactants are dissolved in a pair of immiscible liquids, usually water and a hydrocarbon or chlorinated hydrocarbon. The aqueous phase contains the diol, diamine, dimercaptan, or other active hydrogen compound, an acid acceptor like... 

The present procedure is that of Adams and Ferretti. Another method is the reduction of 1,2-benzenedisulfonyl chloride with zinc powder. In a third method a 2-aminomercaptobenzene is diazotized and converted to an intermediate xanthate and then to the corresponding mercaptosulfonic acid. The latter can be converted to the dimercaptan either by (1) oxidation to a di-sulfonic acid, conversion to the disulfonyl chloride, and reduction to the dimercaptan, or (2) mild oxidation to the corresponding disulfide, conversion to the sulfonyl chloride disulfide, and reduction to the dimercaptan. 

I panol dimercaptan, uses its sulfur atoms in combining with the mer... 

Desulfurization. Alicyclic thiol sulfonates, for example l,2-dithiolane-l,l-dioxide (1, prepared by oxidation of the corresponding dimercaptan) are desul-... 

Poly (thiol esters) from Dibasic Acids and Dimercaptans (Reaction A/M). By this procedure (26), only low molecular weights were obtained because of side reactions. The reaction has therefore not found wider application, compared with the synthesis of polyesters. 

From Dibasic Acids Esters and Dimercaptans (Reaction E/M). This transesterification (31) offers some advantages over other methods. 

From Dibasic Acid Chlorides and Dimercaptans (Reaction C/M). 

In XXXI, when the trans-dimercaptan is replaced by a 70 30 mixture of trans and cis isomers, the melting point is lowered to 240°-255°C. 

The recently developed crab-like method to prepare aza-crowns has been used to prepare thiaaza macrocycles. A crab-like bis-a-chloroamide was reacted with a dimercaptan in DMF or acetonitrile in the presence of sodium or cesium carbonate to give 30-40% yields of the dithia macrocycle (method Y-7) (Bradshaw et al., 1990 Krakowiak et al., 1990). It is possible that similar... 

Two additional methods have been used to prepare thiaaza macrocycles by the formation of C—S bonds. Anisaldehyde reacted with dimercaptans in methylene chloride in the presence of boron trifluoride-etherate to give insoluble 2 2 cyclization products (method Y-8) (Cynkier et al., 1979). A second... 

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