Sulphides, preparation

Bis(butyl tellurium)methyl sulphide, prepared from bis(bromomethyl)sulphide and n-BuTeLi by treatment with 2 equiv of n-BuLi, gives rise to the corresponding bis(lithium methylsulphide), which can be isolated under vacuum as a colourless powder and stored at -20°C for 6 months. It decomposes under argon at 60°C and ignites explosively upon contact with traces of air. 

By boiling in water, with cnprio oxide, the mass con> taining banc sulphide, prepared bj reducing baric sulphate with carbon —... 

G. Taddei7 prepared potassium iodide by adding a dil. soln. of potassium monosulphide to an alcoholic soln. of iodine. In place pf potassium sulphide, J. von Liebig and C. Wittstock used barium sulphide, prepared by calcining sulphate with coke. According to R. Schindler, the products obtained by the sulphide process are contaminated with sulphur compounds. G. S. Serullas treated potassium antimoniate (prepared by calcining tartar emetic) with an alcoholic soln. of iodine as long as the soln. was decolorized. The filtered soln. was evaporated to the point of crystallization. 

Iron Sulphide. Prepare 5 g of a mixture of sulphur and a powder of reduced iron taken in equivalent amounts, transfer it into a test tube, secure the latter in the clamp of a stand, and heat the bottom of the tube on a strong flame until a reaction begins. As soon as this occurs, remove the burner. What is observed Write the equation of the reaction. How can you prove that the compound obtained is a sulphide Test the reaction of iron sulphide with hydrochloric acid. 

Lead Sulphide. Prepare lead sulphide by precipitating it from an aqueous solution of lead acetate, pour the solution off the precipitate, and treat the latter with a dilute nitric acid solution. What is obtained Write the equations of the reactions and explain their course. 

Wiinschendorff,1 using carefully purified arsenious sulphide and the alkali sulphide, prepared the following compounds ... 

Nakazawa H., Osaka T., and Sakaguchi K. (1973) A new cubic iron sulphide prepared by vacuum deposition. Nature 242, 13-14. 

Of the halogenated sulphides prepared and studied only those with the halogen atoms at the end of the carbon chain have vesicant properties. 

Fungal infections superficial dermatophyte or Candida infections purely involving the skin can be treated with a topical imidazole (e.g. clotrimazole, miconazole). Pityriasis versicolor, a yeast infection, primarily involves the trunk m young adults it responds poorly to imidazoles but topical terbinafine or selenium sulphide preparations are effective severe infection may require systemic itraconazole. Invasion of hair or nails by a dermatophyte or a deep mycosis requires systemic therapy terbinafine is the most effective drug. Terbinafine and griseo-fulvin are ineffective against yeasts, for which itraconazole is an alternative. Itraconazole can be used in weekly pulses each month for 3-4 months it is less effective against dermatophytes than terbinafine. 

M0S2 catalysts active in hds and hdm of heavy oils have been prepared in suspension by in situ sulphiding of dissolved Mo complexes (acetylace-tonate, naphthenate ). Unsupported sulphides prepared and used in suspension may have advantages in hds and hdm of residual oils and coal-derived liquids where deactivation of conventional supported catalysts by pore plugging of the support is a problem. Amorphous M0S2 may also be prepared by precipitation from M0Q4 and Li2S in tetrahydrofuran. ... 

The kinetics of the electrochemical reduction of sulphamic acid giving sulphite ion and ammonium hydroxide have been studied polarographically in aqueous solution in the presence of various salts51. The electrodissolution of lead sulphide, prepared by fusion or by sintering in sulphamic acid, has been measured by cyclic voltammetric, potentiodynamic and potentiostatic methods52. 

Sugar liquors, purification of, 50. Sulphides, preparation of, 42. Sulphuric acid, preparation of, 28. 

Alkaline-earth metal sulphides have been prepared by hydrogen reduction of the metal sulphate at high temperatures. Calcium sulphate was reduced at >850 °C, with strontium and barium sulphates being reduced at >950 °C. The products of the reduction were said to be imiform and to contain about 98% sulphide. A method has been described by which the sulphides CaS, SrS, and BaS may be prepared by the reaction of the metals in solution in liquid ammonia with an excess of hydrogen sulphide at temperatures ranging from —78 to —33 °C in high vacuum. Analytical data and lattice parameters of the sulphides prepared in this way were given. 

The configurational inversion of (55 R = R = R = H, m = 1) to the corresponding compound (56) was achieved by applying the Whitham method of concerted fragmentation of a dioxolan derivative. Cyclic sulphides, prepared by the repeatable ring-expansion process, could be converted into carbocycles by a Ramberg-Backlund extrusion of sulphur from the corresponding sulphones e.g., the formation of (57) from the sulphone derived from (56 R = R = H, R = CO Et, n = 3). ... 

Daffodil yellow was used as a term for a cadmium yeUow-type pigment (Fiedler and Bayard, 1986). Church (1915) describes daffodil as a variety of cadmium sulphide prepared at a red heat and containing a small quantity of magnesia . 

Fill a small glass bottle of known volume (100-150 ml) with distilled water and remove dissolved oxygen by bubbling nitrogen gas vigorously for at least 30 min. Add sodium sulphide, NaaS-QHaO, weighing only the driest and cleanest looking crystals, to the extent of 1.5 g for each 100 ml of water. Stopper the bottle so that no air is trapped and invert it several times to dissolve all the sulphide. Prepare this solution on the same day that the method is to be standardized. 

Thiazolo[2,3-c][l,2,4]benzothiadiazines [CgNS-CsNaS-Ce].—Cyclization of the sulphide prepared by condensation of ethyl a-chloroacetoacetate with 6-chloro-3-mercapto-4//-[l,2,4]benzothiadiazine 1,1-dioxide with acetic anhydride in the... 

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