Potassium hydroxide hypoiodite

Acetaldehyde reacts with phosphoms pentachloride to produce 1,1-dichloroethane [75-34-3] and with hypochlorite and hypoiodite to yield chloroform [67-66-3] and iodoform [75-47-8], respectively. Phosgene [75-44-5] is produced by the reaction of carbon tetrachloride with acetaldehyde in the presence of anhydrous aluminum chloride (75). Chloroform reacts with acetaldehyde in the presence of potassium hydroxide and sodium amide to form l,l,l-trichloro-2-propanol [7789-89-1] (76). 

G. F. Schonbein, as previously indicated, found that when iodine water is mixed with potassium hydroxide, the analogy of the product with soln. of the hypo-bromites and hypochlorites shows that potassium hypoiodite is in all probability formed by a reversible reaction, 2KOH +I2 KI +KOI+H20, and that, when in equilibrium, the addition of potassium iodide will reverse the reaction, forming free iodine and potassium hydroxide. Hence, (i) the amount of potassium hydroxide required to complete the reaction must be greater than is indicated by the equation, as was found to be the case by R. L. Taylor and (ii) the failure of many to obtain evidence of bleaching soln. of hypoiodite when soln. of iodine in potassium iodide are employed. If a large excess of potassium iodide is present, this will prevent... 

The reaction is the same as that involved in the usual chemical preparation of iodoform, whereby a colorless solution of hypoiodite (obtained by dissolving iodine in a sufficient quantity of potassium-hydroxide solution) is made to react with alcohol. The decomposition potential of potassium iodide, investigated by Dony-Henault,2 show s that the iodine as such does not act on the alcohol, but only after its conversion into hypoiodite. The iodine ions are set free at the same anode potential no matter if alcohol is added or not. The alcohol does not act as a depolarizer towards the iodine ion the electrical iodoform synthesis is a typical secondary process. 

Iodoform2 from Acetone.—Teeple3 mentions a method by which almost the theoretical yield of iodoform can be obtained by the electrolysis of a potassium-iodide solution in the presence of acetone. No diaphragm is required, the essential feature being the gradual addition of a substance like hydrochloric acid, hydriodic acid, or, better, iodine, to neutralize the excess of potassium hydroxide as fast as it is formed. The tempera-, ture is kept below 25°, and the electrolyte thoroughly stirred in fact the same current conditions should be observed as in the case of chloroform above mentioned, the aim in this case also being to maintain the conditions always favorable for the production of a maximum amount of hypoiodite. 

Potassium hypoiodite, KOI.—The hypoiodite has not been isolated, but is formed in aqueous solution by the interaction of iodine and a dilute solution of potassium hydroxide ... 

If freshly precipitated, magnesium hydroxide is tinted deep brown-red by a solution of iodine in potassium iodide. The color fades on digestion with potassium iodide, alcohol, potassium hydroxide or other solvents for iodine. It is also discharged by treatment with sulfite or thiosulfate. Likewise, when magnesium hydroxide is formed in the presence of free iodine, the precipitate is brown-red. It is obviously an adsorption compound of magnesium hydroxide and iodine. The most suitable conditions for the formation of this colored product (even in dilute solution) are attained when an iodine solution is decolorized with sodium or potassium hydroxide immediately before the addition of the magnesium salt. In the hypoiodite solution, the following equilibrium prevails ... 

Crystalline nitrogen triiodide can be prepared by reaction of aqueous iodine monochloride (ICl) alkalized by potassium hydroxide with aqueous ammonia. On cooling, nitrogen triiodide forms as blackish-brown shiny needles, up to 2 mm long [54, 66], Nitrogen triiodide is also formed by addition of ammonia to alkaline solutions of potassium hypoiodite (KIO) [54]. Other iodizing agents such as iodine monobromides or dibromoiodides can be used as well [46]. 

A few polymerizations leading to nonhydrolyzable polysaccharides have been reported. The first was a base-catalyzed polymerization of 5,6-anhydro-l,2-0-isopropylidene-3-0-methyl-a-D-glucofuranose.u The polymerization was initiated most successfully with solid potassium or cesium hydroxide, and the d.p. achieved was —25. Hydrolysis gave a free, methylated, nonhydrolyzable polysaccharide, which was oxidized with hypoiodite to the poly(D-gluconic acid.)... 

Diiodocyclopropanes are fairly unstable compounds furthermore, their stability depends on the eonditions under which they are synthesized. The products are particularly prone to hypoiodite or iodate ions present in the phase-transfer catalytic system.Thus 7,7-di-iodobicyclo[4.1.0]heptane (2) obtained using iodoform/sodium hydroxide/phase-transfer catalyst is unstable even in solution, while if prepared using iodoform/potassium /err-butoxide, it can be isolated by vacuum distillation in moderate yield (however, for a different observation, see ref 127). 

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