Carbon disulfide, reaction with alcohols

The required xanthates 1 can be prepared from alcohols 5 by reaction with carbon disulfide in the presence of sodium hydroxide and subsequent alkylation of the intermediate sodium xanthate 6. Often methyl iodide is used as the alkylating agent ... 

The reaction of compound 376 with hydrazine gives product 377 that has been transformed into similar triazoles 378, after reaction with carbon disulfide in the presence of alcoholic potassium hydroxide, benzoic acid in the presence of phosphoms oxychloride, or 3-[bis-(methylthiomethylene)]pentan-2,4-dione and l,l-dicyano-2,2-dimethylthioethylene, in refluxing -butanol (Scheme 40) (Table 55) <2000FES641>. 

If the hydroxy group of a 2-amino alcohol is replaced by a mercapto group (XCIX) the reaction with carbon disulfide yields thiazolidine-2-thiones (C) with liberation of hydrogen sulfide. This method though is practically never used since thiazolidine-2-thiones are more simply obtained from 2-halo amines (see further under Section IV.l) which are themselves starting materials for the 2-amine thiols. 

OXICLORURO de FOSFORO (10025-87-3) Fumes in moist air. Contact with water, steam, or alcohols produces hydrochloric acid, phosphoric acid, and phosphine gas, which is pyrophoric, with possible ignition or explosion (may be a delayed reaction). Contact with air produces corrosive fumes. Violent reaction with carbon disulfide, 2,6-dimethylpyiidine-M-oxide, dimethyl sulfoxide, ferrocene-l,l -dicarboxylie acid, pyridine, zinc powder. Reacts, possibly -violently, with acids, alkali metals, alkalis, combustible materials, dimethyl formamide, organic matter, zinc powder. Incompatible with acetic anhydride, iV,A -dimethyl formamide, 2,5-dimethylpyrrole, sodium. Rapid corrosion of steel and most metals, except lead, occurs in the presence of moisture. 

Commercial hexythiazox is a racemic mixture of the two trans enantiomers Scheme 26.2.2 shows the main synthetic pathways [11, 17, 19]. Starting from 4-chloro propiophenone the key intermediate erythro amino alcohol may be obtained by stereoselective catalytic reduction of the corresponding hydroxy imi-noketone or by sodium borohydride reduction of the aminoketones obtained via Gabriel synthesis. Different routes lead from this aminoalcohol to the trans-thiazolidinone system the basis of all routes is activation of the hydroxy group, e.g., in form of the sulfonate and a ring forming reaction with carbon disulfide or carbonyl sulfide. The final acylation of the NH group with cyclohexyl isocyanate leads to hexythiazox. 

The alkah metal xanthates are generally prepared from the reaction of sodium or potassium hydroxide with an alcohol and carbon disulfide. The initial reaction is the formation of the alkoxide, which reacts with carbon disulfide to give the xanthate ... 

Alcohols can be dehydrated via xanthate esters at temperatures that are much lower than those required for acetate pyrolysis. The preparation of xanthate esters involves reaction of the alkoxide with carbon disulfide. The resulting salt is alkylated with methyl iodide. 

The reaction of 2-aminobenzyl alcohol 376 with 2-chloro-4,5-dihydroimidazole afforded [2-(4,5-dihydro-177-imidazol-2-ylideneamino)phenyl]methanol hydrochloride 377, which upon treatment with carbon disulfide gave l-(477-3,l-benzoxazin-2-yl)imidazolidine-2-thione 378 (Scheme 71). The assumed reaction mechanism involved the initial formation of the dithiocarbamate 379, which underwent intramolecular nucleophilic addition to furnish the unstable thiazetidine 380. By nucleophilic attack of the hydroxy group on the carbon atom of the thiazetidine ring, thiocarbamate derivative 381 was formed, which gave the final 3,1-benzoxazine 378 by an intramolecular cyclocondensation with the evolution of H2S <2006H(68)687>. 

Reaction of N-(2-aminobenzoyl)-2-aminobenzyl alcohol (711JC647) or anthraniloyl anthranilic acids (597) (76JIC382) with carbon disulfide gave the 3-(2-carboxyphenyl)-2-mercaptoquinazolin-4-ones (598), which underwent cyclodehydration to the title compounds 599 (76JIC382). 

Methyl isothiocyanate has been prepared from methyl thiocyanate by rearrangement with heat1 and from A, A /-dimethyl-thiuramdisulfide by the action of iodine 2 or by heating with water or alcohol.3 The most useful method of preparation has been the reaction of methylamine with carbon disulfide to form methyl-... 

Interest in the xanthates of carbohydrates has arisen almost entirely through the importance of the viscose process in the technical production of rayon and related products.126 The selective character of the reaction of carbon disulfide and alkali with polyhydroxy compounds has been studied. Lieser and Nagel126 found that a monoxanthate is formed with polyhydric alcohols and methyl a-D-glucopyranoside when they react with carbon disulfide and aqueous barium hydroxide. The xanthation that has been demonstrated in the cases of glycerol 1,3-dimethyl ether and levoglucosan (LXIX) shows that secondary hydroxyl groups can... 

Radical deoxygenation of alcohols is important, and the reduction of xanthates prepared from alcohols, with Bu3SnH in the presence of AIBN is called the Barton-McCombie reaction (eq. 2.13) [37-51]. The driving force for the reaction is the formation of a strong C=0 bond from the C=S bond, approximately 10 kcal/mol stronger. This reaction can be used for various types of substrates such as nucleosides and sugars. Though methyl xanthates, prepared from alcohols with carbon disulfide and methyl iodide under basic conditions are very frequently used, other thiocarbonates, as shown in eq. 2.14, can also be employed. 

Fig (19) Octalin ketal (163) is converted to kete dithioacetal (164) by the cleavage of ketal function and condensation with carbon disulfide and methyl iodide. Subjection of (164) to the action of dimethylsulfonium niethylide and acid hydrolysis leads to the formation of unsaturated lactone (165).lts furan silyl ether derivative is caused to undergo Diets-Atder reaction with methyl acrylate to obtain salicyctic ester (166) which is converted by standard organic reactions toabietane ether (167). It is converted to aiiylic alcohol (168) by epoxidation and elimination. Alcohol (169) obtained from (168) yields orthoamide which undergoes transformation to amide (170). Its conversion to the previously reported intermediate has been achieved by epoxidation, elimination and hydrolysis. 

Carbonyl transposition.1 Tetrafluoroboric acid is the most effective acid for rearrangement of a-hydroxy ketene dithioketals to a,p-unsaturated thiol esters. This rearrangement is particularly useful for rearrangement of the tertiary allylic alcohols formed by addition of organometallic reagents to a-keto ketene dithioketals, which are readily available by reaction of ketone enolates with carbon disulfide followed by alkylation with methyl iodide. 

A thiete intermediate (225a) was proposed in the photochemical reaction of dimethyl acetylenedicarboxylate with 225,and similar intermediates were proposed in the addition of thiones or dithioesters to heteroatom-substituted acetylenes. Thiete 227 was suggested as an intermediate in the reaction of 226 with carbon disulfide. Reactions of aryl vinyl sulfide derivatives (2,4,6-trinitrobenzenesulfonate of a phenylthiovinyl alcohol, a phenacyl derivative )... 

A facile one-pot synthesis of thiophosphoryl xanthates was carried out by using a mild base DBU-catalysed sequential reaction of excess alcohols with carbon disulfide and diethoxy thiophosphoryl chloride. ... 

The formation of xanthates (77) by reaction of an alcohol with carbon disulfide in the presence of alkali (the xanthate reaction) (Scheme 40) is of considerable industrial importance since it forms the basis of the manufacture of rayon and cellophane (see... 

Derivation (a) Addition of carbon disulfide to an alcoholic solution of ethylenediamine followed by neutralization with sodium hydroxide, or (b) by reaction of ethylenediamine with carbon disulfide in aqueous sodium hydroxide. 

The reaction of carbon disulfide with 2-amino alcohols (LVIII) can give rise to the formation of thiazolidine-2-thiones (LX) 81, 219, 247, 294, 34S ) as well as oxazolidine-2-thiones (LXI) 27, 47, 324, 348). 

C. Yet another and very elegant method has been worked out by Rosen 292). The reaction of amino alcohols with carbon disulfide is carried out in the presence of iodine. In this way N-(2-hydroxyalkyl)-thiuram disulfides (LXVIII) are formed which may be thermally decomposed into the oxazolidine-2-thiones (LXI). These reactions are... 

The remarks made above in connection with the reaction of carbon disulfide with 2-amino alcohols are also valid for its reaction with... 

The same considerations which hold for 2- or 3-amino alcohols also apply for the reaction of carbon disulfide with o-amino benzyl alcohols. In the presence of alkali l,4-dihydro-2H-3,l-benzothiazine-2-thione (LXXIVa) [253, 272] is formed and without alkali the 1,4-di hydro-2 H-3,l-bcnzoxazine-2-thione (LXIVb) [217, 229, 271]. 

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