Iodine-lead acetate

SAFETY PROFILE Experimental poison by subcutaneous route. Moderately toxic to humans by ingestion. Moderately toxic experimentally by ingestion, intraperitoneal, and intravenous routes. An experimental teratogen. Human systemic effects by multiple and unspecified routes toxic psychosis, excitement, respiratory stimulation, nausea or vomiting, and sweating. Experimental reproductive effects. Mutation data reported. A powerful irritant which affects the central nervous system. Incompatible with ferric salts, mineral acids, iodine, lead acetate, silver nitrate, sodium phosphate powder. When heated to decomposition it emits toxic fumes of Na20. 

Incompot Ferric salts, lime water, spirit nitrous ether, mineral acids, iodine, lead acetate, silver nitrate, sodium phosphate in powder. 

Salicylic acid Iodine, iron salts, lead acetate... 

Manufacture. Trichloromethanesulfenyl chloride is made commercially by chlorination of carbon disulfide with the careful exclusion of iron or other metals, which cataly2e the chlorinolysis of the C—S bond to produce carbon tetrachloride. Various catalysts, notably iodine and activated carbon, are effective. The product is purified by fractional distillation to a minimum purity of 95%. Continuous processes have been described wherein carbon disulfide chlorination takes place on a granular charcoal column (59,60). A series of patents describes means for yield improvement by chlorination in the presence of dihinctional carbonyl compounds, phosphonates, phosphonites, phosphites, phosphates, or lead acetate (61). 

Sodium thiosulfate is determined by titration with standard iodine solution (37). Sulfate and sulfite are determined together by comparison of the turbidity produced when barium chloride is added after the iodine oxidation with the turbidity produced by a known quantity of sulfate iu the same volume of solution. The absence of sulfide is iadicated when the addition of alkaline lead acetate produces no color within one minute. 

Quinoline Salicylic acid Silicon Dinitrogen tetroxide, linseed oil, maleic anhydride, thionyl chloride Iodine, iron salts, lead acetate Alkali carbonates, calcium, chlorine, cobalt(II) fluoride, manganese trifluoride, oxidants, silver fluoride, sodium-potassium alloy... 

Dextrin and Sugars. The ink is diluted somewhat with water and treated with basic lead acetate to eliminate any gum present. After filtration, the excess of lead is eliminated by means of hydrogen sulphide and a large amount of alcohol then added any dextrin is precipitated in whitish flocks, which arc allowed to settle ami then dissolved in water. This solution should give a marked dextro-rotation and should Ix-comr reddish when treated with tincture of iodine. 

Similar to the Prevost Reaction, initial addition of iodine leads o a cyclic iodonium ion, that is opened through nucleophilic substitution by acetate anion ... 

Lead acetate Potassium dichromate and concentrated sulfuric acid Sodium nitrite Copper sulfate Mercury (II) chloride Yellow precipitate of lead iodide soluble in excess hot water Liberation of iodine Liberation of iodine Brown mixed precipitate Scarlet precipitate of mercury (II) iodide... 

As in Experiments 12 and 13 the solid effervesces in the concentrated sulphuric acid and the gas evolved fogs the breath (even more markedly in this case), turns litmus red, and gives a dense smoke with ammonia. When the tube is warmed, the beautiful purple iodine vapor is seen inside and nearly black crystals collect on the cooler upper walls. Lead acetate paper is colored dark brown. Sometimes a powdery light yellow substance (sulphur) is seen collecting on the walls of the tube. 

Catalysis of the iodine-azide reaction by thiosulphate leads to very rapid reaction for which no kinetic data are available. Raschig proposed the intermediate 8203 , and this has been considered more fully . Weiss suggested that all these reactions involve iodine atoms. In the absence of kinetic measurements discussion is premature. The corresponding tetrathionate system has received kinetic study. Dodd and Griffith found evidence for some direct decomposition of the thionate by iodide and iodine in acetate buffers, and they propose the reactions... 

For purification, the crystalline hexaatomic sulfur is dissolved in benzene (approx. 100 mg./l.) toluene is not suitable (see Properties). The benzene solution is extracted with a series of reagents, three or four extractions being made with each reagent except where otherwise indicated. (For 200 ml. of benzene solution, 50-ml. portions of reagent are used). The reagents are employed in the following order (1) water, (2) 10% aqueous potassium triiodide, until the benzene phase remains colored from iodine, (3) 10% aqueous potassium iodide, (4) water, (5) 5% aqueous lead acetate, twice, (6) water, (7) 5 % aqueous potassium hydroxide, once, (8) water. The purified solution is dried over magnesium sulfate and should be used immediately. The approximate concentration of Sg can be determined spectro-photometrically at 300 mju (e = 181 l./g.-atom) after suit-... 

Of the two possibilities, 80 and 81, the former is preferred partly on biogenetic arguments and partly on the basis of the NMR spectra of roxburghine-D and the iodine-sodium acetate product (83 or 84) If vincoside (86) is postulated to be an intermediate in the biosynthesis of the roxburghines, subsequent unexceptional reactions could lead to the biochemical equivalents of 87 and 88 condensation of the last intermediate with tryptamine would then give a compound of structure 80. 

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