Sodium thiocarbonate

A double end point, acid—base titration can be used to determine both sodium hydrosulfide and sodium sulfide content. Standardized hydrochloric acid is the titrant thymolphthalein and bromophenol blue are the indicators. Other bases having ionization constants in the ranges of the indicators used interfere with the analysis. Sodium thiosulfate and sodium thiocarbonate interfere quantitatively with the accuracy of the results. Detailed procedures to analyze sodium sulfide, sodium hydro sulfide, and sodium tetrasulfide are available (1). 

Sodium ferro-heptanitroso sulphide, NaFe4(NO)7S3.2H20, may be obtained in a similar manner to the potassium salt by boiling a solution of sodium ferro-dinitroso thiosulphate, as also by the action of sodium nitrite and sulphide solutions upon ferrous sulphate. In this latter reaction the sodium sulphide may be replaced by sodium thiocarbonate, Na2CS3. 

Sodium thiocarbonate. See Sodium trithiocarbonate Sodium thiocyanate... 

Synonyms Sodium thiocarbonate Empiricai CNa2Ss Formula S=C(SNa)2 Properties M.w. 154.19 Uses Metal precipitant for treatment of wastewater and other heavy metal-contg. liqs. insecticide... 

Under similar conditions, perfluoroalkyl iodides react with alkyl phosphates to give fluorinated phosphine oxides, phosphinates, and phosphines [54 (equation 49) The product formed depends upon the stoichiometry and type of iodide used. When sodium alkyl trithiocarbonates are used as substrates, perfluoroalkyl tri-thiocarbonates ate formed [55]. 

In 1863 Husemann prepared an intermediate, to which he assigned the formula C2H4S, by the action of sodium sulfide on ethylene bromide. From it he obtained the cyclic dimer, dithiane, by distillation. Mans-feld (1886) reinvestigated the intermediate and concluded that it is a polymer. As a reminder of the significance of the term polymer at that time it is to be noted, however, that Mansfeld suggested the cyclic trimeric formula for the intermediate, which is now known to be a linear polymer. Other polymers prepared similarly by Husemann (1863) include methylene sulfide (—CH2—S—)a and methylene tri-thiocarbonate (—CH2—S—CS—S—) . Neither was recognized as a polymer, and neither has since been investigated from this standpoint. 

Calcium and sodium carbonates react with the acid forming the corresponding thiocarbonates, thus ... 

Sodium perthiocarbonate, Na2CS4, is formed when an alcoholic solution of sodium sulphide is converted into the disulphide by the addition of sulphur and subsequently treated with carbon disulphide.2 Perthiocarbonates may also be formed by the direct combination of thiocarbonates with sulphur.3 There is no analogy to this latter method of preparation in the case of percarbonates this fact is usually regarded as illustrating the superior chain-forming power of sulphur atoms as compared with oxygen atoms. 

Hydroxypyridines may be thioacylated using benzotriazole reagents. The sodium salt of 3-hydroxypyridine reacts with aryloxythiobenzotriazole 97 to give thiocarbonate 98 in good yield <2005JOC7866> (Equation 66). 

Platinum Thiocarbonate is obtained in combination with 2 molecules of ammonia, PtCS3(NH3)2.H20, by crystallisation from a mixture of potassium chlor-platinite, concentrated ammonia and carbon disulphide.2 It yields red needles, insoluble in cold water, ammonium or sodium hydroxide. Exposed over sulphuric acid in vacuo it becomes anhydrous. 

The most significant discovery in the history of carbohydrate thiocarbonates was reported in 1892 by Cross, Bevan, and Beadle, who found that cellulose reacts with a mixture of aqueous sodium hydroxide and carbon disulfide to give a soluble dithiocarbonate derivative, from which cellulose can be regenerated. This observation, the basis of the Viscose process, was made at a time when only one other polyhydric alcohol thiocarbonate, that of glyceritol, was known. The subsequent industrial development of... 

Very little information is available concerning the thermal stability of the metallic salts of the acid carbonates and thiocarbonates. Calcium glyc-eritol dicarbonate [C3H60H(C0s )2Ca ], although very unstable in solution, could be stored at room temperature in an anhydrous state for a short period of time. On being strongly heated it charred, with the evolution of acrolein. A hydrated 0-(sodium thiocarbonyl) derivative of cellulose became insoluble in alkali within 24 hours at room temperature, due to decomposition. On the other hand, many metal xanthates, particularly the insoluble copper salts, which are readily obtained in a pure, anhydrous state, appear to be reasonably stable at about 20°. This very limited evi-... 

In their comparative studies, Rogovin and coworkers confirmed the sensitivity of 0-(methoxycarbonyl)celluloses toward aqueous alkali, noted earlier by Heuser and Schneider, but found an 0-[(methylthio)thiocar-bonyl] derivative to possess enhanced stability, similar to that of cellulose acetate. Thus, whereas the action of N sodium hydroxide at 25° causes almost complete de-esterification of O-(methoxycarbonyl) cellulose in 5 minutes, the methyl xanthate suffers only 20 % hydrolysis during 1 hour. No quantitative data of this nature are available for the corresponding mono-thiocarbonate. The product from its iodine oxidation was far more stable than that (see p. 147) derived from cellulose xanthate. The 0-[(methyl-thio)thiocarbonyl] derivative of methyl a-D-glucopyranoside was seemingly more alkali-sensitive than the cellulose analog described above, possibly on account of its higher solubility. 

Coupling of a benzoic acid derivative under basic conditions is achieved with alkyl iodides," alkyl chlorides,dimethyl sulfate, or (l,1-dihydroperfluoroalkyl)phenyliodonium triflates. Common bases used arc potassium carbonate or sodium hydroxide (with phase-transfer catalyst). " Again, employing acid chlorides " - or anhydrides, " is the method of choice. The reaction can be performed without further activation, " " but in most cases the transformation takes place in the presence of the usual bases, triethylamine - " or pyridine " " " " " [in some cases 4-(dimethylamino)pyridine is added " ]. In a similar manner carbamates. thiocarbamates, " or thiocarbonates are synthesized. Perfluoropropcn-2-ol... 

---