Iodine trichloride preparation

Iodine trichloride [865-44-17, ICl, mol wt 233.39, 54.40% I, is a yellow or brownish powder. It is pungent and has a very irritating odor. It decomposes at 77°C iato ICl and CI2. It is prepared by adding finely powdered iodine to an excess of Hquid chlorine. It is used as a chlorinating and oxidising agent (120). 

Iodine trichloride is prepared by adding iodine to liquid chlorine in a stoichiometric amount ... 

Chlorine and iodine.—In the course of his historic research on iodine, J. L. Gay Lussac (1814) 6 prepared a compound of iodine and chlorine by the action of chlorine gas on iodine—the gas was absorbed by the solid forming a reddish-brown liquid which is so remarkably like bromine, that before that element had been recognized as a distinct chemical individual by A. J. Balard, J. von Liebig mistook bromine for iodine chloride. If the chlorine be in excess, citron-yellow needle-like crystals are formed. The liquid product is iodine monochloride the crystalline solid is iodine trichloride. H. Davy called the product formed by the action of iodine on chlorine, olilorionio acid, and he regarded it as a compound consisting of one proportion of iodine and one of chlorine —i.e. iodine monochloride. 

Iodine trichloride.—This compound was discovered by J. L. Gay Lussac as the result of treating warm iodine or iodine monochloride with an excess of chlorine. The trichloride collects as a citron-yellow crystalline sublimate on the cooler parts of the vessel. It is also formed by the action of liquid chlorine on iodine, or an iodide—say lead iodide.18 The iodine trichloride is almost insoluble in liquid chlorine, and hence, say Y. Thomas and P. Dupuis, this method of preparation is very convenient. It is also formed by the action of dry chlorine on hydrogen iodide (A. Christomanos) silver iodate (J. Krutwig) or methyl iodide (L. von... 

To prepare iodine trichloride, heat 20 grms. of iodine in a retort, A, Fig. 26, which delivers into a glass balloon II filled with chlorine, and connected with a Kipp s apparatus C delivering chlorine. The chlorine is rapidly absorbed as soon as it comes in contact with the vapour of iodine, and reddish-yellow crystals of iodine trichloride are formed on the walls of the balloon. The excess of chlorine is finally expelled by a stream of carbon dioxide.. If the crystals are desired, the balloon must bo broken if a soln. of iodine trichloride is desired, the crystals can be dissolved in about ten times their weight of water. 

Fig. 64. Apparatus for preparing iodine trichloride (a) and funnel with a filtering bottom for filtration in an inert atmosphere with cooling (b)...

Transfer the iodine trichloride from the flask into a weighed drawn out test tube. Cool the tube with dry ice and rapidly seal it wear eye protection ). Weigh the test tube with the substance and the remaining fragments of the tube. Calculate the yield in per cent. Write the equation of the reaction. Use the prepared iodine trichloride in the following syntheses. 

Preparation of Potassium Tetrachloroiodate Dihydrate. Dissolve 18 g of iodine trichloride in 20 ml of concentrated hydrochloric acid with vigorous stirring in a round-bottomed flask with a ground-glass stopper. Cool the solution to 0 °C and add to it a mixture of 5 g of potassium chloride and 12 ml of a concentrated hydrochloric acid solution. Dilute the reaction mixture to twice its volume with concentrated hydrochloric acid cooled to 0 °C. 

The usual method of preparing iodine trichloride by subliming iodine into a current of chlorine gas is tedious and gives a poor yield of a product contaminated with iodine and iodine monochloride. Furthermore, the product deposits on the sides of the flask in crusts which are difficult to remove. 

The preparation of 1-IB5H8 in high yield has been accomplished by reacting pentaborane(9) with iodine 183.184>, iodine monochloride 185> or iodine trichloride 183>. This compound is a thermally stable crystalline solid which decomposes slowly on contact with the atmosphere 183>. The apically substituted compound is apparently much more stable... 

Iodine trichloride can be prepared by the reaction of an excess of liquid chlorine with solid iodine and then allowing the excess chlorine to evaporate from the solid IC13. 

Alicyclic, aromatic, aliphatic, steroidal and triterpenoid 1,2-diols are cleaved by iodine triacetate and iodine(I) acetate to generate carbonyl compounds. Aldehydic products are not further oxidized. Iodine triacetate is prepared from iodine trichloride and silver(I) acetate, whereas iodine(I) acetate is prepared from iotUne and silver(I) acetate. Reactions occur in acetic acid at room temperature under nitrogen, and a radical pathway involving a hypoiodite is suggested. The cost and the availability of these reagents are probable reasons for their unpopularity. 

Diaryliodonium compounds can be prepared by acid-catalyzed condensation of iodoso aryls with another aryl molecule (equation 129). Another method is the use of iodine trichloride in reaction with organometalUc compounds (equations 130 and 131). RICI2 may be prepared by direct chlorination of RI (R = CF3CH2, CHF2(CF2)sCH2) and these materials can be used to chlorinate iodobenzene to give the less hydrolytically stable compound PhICl2. ... 

Iodine triacetate, IfOCOCHsIj, which is prepared from iodine trichloride and silver acetate in acetic acid at room temperature, cleaves vicinal diols to dialdehydes [779]. 

Iodine trichloride, ICI3, is usually prepared by a low-temperature reaction of iodine with liquid chlorine by the method of Booth and Morris [2], It is obtained in the form of a fluffy orange solid that easily decomposes... 

Chlorovinyliodine(III) dichloride (18), a useful reagents for the synthesis of aryliodonium salts, is prepared by addition of iodine trichloride to acetylene in concentrated hydrochloric acid (Scheme 2.8) [71,88,89], Caution product 18 should be handled with a great care it is extremely unstable and decomposes autocatalytically within seconds. It can, however, be stored for weeks in a freezer at -20 °C or below [71,89]. 

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