Manganese salts iodide

These are usually reactions of anhydrous transition and B metal halides with dry alkali metal salts such as the sulphides, nitrides, phosphides, arsenides etc. to give exchange of anions. They tend to be very exothermic with higher valence halides and are frequently initiated by mild warming or grinding. Metathesis is described as a controlled explosion. Mixtures considered in the specific reference above include lithium nitride with tantalum pentachloride, titanium tetrachloride and vanadium tetrachloride, also barium nitride with manganese II iodide, the last reaction photographically illustrated. 

In 2012, Yong and Teo [146] reported the use of manganese salts for the A7-heteroarylation of indoles and indazoles with heteroaryl iodides (e.g., pyridyl iodides) and MnF as the catalyst. The low cost and ready availability of Mn S2ilts were the driving force behind this study. The conditions included using 20 mol% MnFj as the with fr KS-l,2-diaminocyclohexane (40 mol%) CsjCOj (2 equiv) in water at 130 °C between 24 and 48 h. 

Alkali bromides, chlorides, sulfates, and nitrates interfere only when very small amounts of iodide are to be detected. Bromides have the greatest deleterious effect however, when the amount of bromide is approximately known, small amounts of iodine may still be detected if a comparative test is carried out. Metal salts which give colored aqueous solutions interfere (Fe , UOa, Ni, Cu, Co). Cyanides, mercuric, silver, and manganese salts impair the reaction, as do compounds which reduce Ce. In such cases the difficulty may occasionally be averted by using more concentrated ceric solutions. Under the experimental conditions, barium and strontium salts are precipitated as sulfates, which are colored yellow by coprecipitation of ceric salt. Osmium salts behave similarly to iodides. 

Primary halides (and some secondary cases) may be oxidized directly to carbonyl compounds by reaction with chromate ion, either in the presence of crown compounds, or with the chromate associated with a polymer matrix. Reduction of low molecular weight halides to hydrocarbons has been reported in superacid media [e.g. HF-TaFs), and a hydride transfer pathway is suggested. Allyl iodides may be reduced with triphenylphosphonium hydriodide (equation 10), but acid sensitive groups may not survive these conditions. Vinylic and aryl halides are converted into the parent hydrocarbons by reaction with Grignard reagents and a catalytic quantity of manganese salts a reaction mechanism has been proposed. 

This reaction is also used on a large scale, to obtain iodine from seaweed. The ash from burnt seaweed ( kelp ) is extracted with water, concentrated, and the salts other than iodides (sulphates and chlorides) crystallise out. The more soluble iodides remain and the liquor is mixed with sulphuric acid and manganese dioxide added the evolved iodine distils off and is condensed. 

Seaweeds. The eadiest successful manufacture of iodine started in 1817 using certain varieties of seaweeds. The seaweed was dried, burned, and the ash lixiviated to obtain iodine and potassium and sodium salts. The first process used was known as the kelp, or native, process. The name kelp, initially apphed to the ash of the seaweed, has been extended to include the seaweed itself. About 20 t of fresh seaweed was used to produce 5 t of air-dried product containing a mean of 0.38 wt % iodine in the form of iodides of alkah metals. The ash obtained after burning the dried seaweed contains about 1.5 wt % iodine. Chemical separation of the iodine was performed by lixiviation of the burned kelp, followed by soHd-Hquid separation and water evaporation. After separating sodium and potassium chloride, and sodium carbonate, the mother Hquor containing iodine as iodide was treated with sulfuric acid and manganese dioxide to oxidize the iodide to free iodine, which was sublimed and condensed in earthenware pipes (57). 

Rubidium metal alloys with the other alkaU metals, the alkaline-earth metals, antimony, bismuth, gold, and mercury. Rubidium forms double haUde salts with antimony, bismuth, cadmium, cobalt, copper, iron, lead, manganese, mercury, nickel, thorium, and 2iac. These complexes are generally water iasoluble and not hygroscopic. The soluble mbidium compounds are acetate, bromide, carbonate, chloride, chromate, fluoride, formate, hydroxide, iodide. 

Dissolved mineral salts The principal ions found in water are calcium, magnesium, sodium, bicarbonate, sulphate, chloride and nitrate. A few parts per million of iron or manganese may sometimes be present and there may be traces of potassium salts, whose behaviour is very similar to that of sodium salts. From the corrosion point of view the small quantities of other acid radicals present, e.g. nitrite, phosphate, iodide, bromide and fluoride, have little significance. Larger concentrations of some of these ions, notably nitrite and phosphate, may act as corrosion inhibitors, but the small quantities present in natural waters will have little effect. Some of the minor constituents have other beneficial or harmful effects, e.g. there is an optimum concentration of fluoride for control of dental caries and very low iodide or high nitrate concentrations are objectionable on medical grounds. 

A galvanic cell involves the overall reaction of iodide ions with acidified permanganate ions to form manganese(II) ions and iodine. The salt bridge contains potassium nitrate. 

As is true for other classes of aromatic nucleophilic substitution, the halogen displacement can frequently be catalyzed by copper or copper(I) salts. Using sodium hydride as the base and copper(I) iodide as catalyst, a series of o-bromophenylethylamine derivatives, including both amides and carbamates, have been cyclized. Oxidation to the indole can be effected with manganese dioxide (81JCS(P1)290). 

The recovery of important metals or their salts is possible by electrolysis in cells provided with ion-selective membranes, e.g. of uranium (71, 72, 73, 75), of magnesium from sea water (130), of iodine from iodide containing brines (158), of manganese (74). 

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