Green, Acid Iodine

Bayberry Wax. Bayberry wax [8038-77-5] is removed from the surface of the berry of the bayberry (myrtle) shmb by boiling the berries in water and skimming the wax from the surface of the water. The wax is green and made up primarily of lauric, myristic, and palmitic acid esters. The wax has a melting point of 45°C, an acid number of 15, a saponification number of 220, and an iodine number of 6. The wax has an aromatic odor and is used primarily in the manufacture of candles and other products where the distinctive odor is desirable. 

Collections of fundamental and thermodynamic data can be found in an earlier review [158] and in standard resources [13, 14]. However, due to the reactivity of iodine there are many less common or more reactive forms of iodine that have been less well characterized. For example, a blue 12 cation, a brown I3+, or a green I5+ cation are formed in concentrated sulfuric acid and 1+ is stabilized in donor environments such as pyridine [159]. So-called hypervalent iodine reagents have been developed as a versatile oxidation tool in organic synthesis and often iodine derivatives are employed as electron transfer catalysts. Some fundamental thermodynamic data and typical applications of iodine are summarized in Scheme 5. 

Dihydroxynaphthalene (15 g) was dispersed in 350 ml of acetic acid and then heated to 80°C. The mixture was treated with a spatula tip of iodine and the dropwise addition of 30 ml of bromine over a period of 90 minutes and then stirred at 80°C for an additional hour. After decanting off the green solution and recrystallizing the solid twice in acetic acid 28 g of product was isolated as brownish crystals. 

A. J. Balard 8 prepared an olive-green insoluble mass by the action of bromine water on copper oxide, vegetable colours are not bleached, but nitrogen is evolved from ammonia, and carbonic and other acids set free bromine. When heated, oxygen, bromine, and water are given off, and copper oxybromide remains. The solid is possibly a mixture of bromine and copper oxybromide and not copper hypobromite. A. J. Balard also prepared a soln. which probably contained silver hypobromite by the action of bromine water on silver oxide. The product easily decomposes into bromide and bromate. F. W. Schmidt suggested that the white floccuient precipitate obtained by the action of iodine on a very dil. ammoniacal soln. of silver nitrate is possibly silver hypoiodite. 

Various microchemical tests are available for the detection of minute quantities of sulphur, both free and combined. The substance under examination may be treated with a little sodium hydroxide solution, the extract evaporated just to dryness, a few drops of aqueous sodium cyanide (0-1 per cent.) added and the evaporation repeated. The residue, moistened with dilute sulphuric acid and a drop of ferric chloride, gives the characteristic ferric thiocyanate colour if sulphur is present.6 In the ease of minerals, traces of sulphur dioxide produced on heating may be detected 6 by the colour change of an alkaline solution of Bromocrcsol Green or by the deeolorisation of starch-iodine solution. 

The condensation is carried out in the usual manner in chloroform solution. The product separates from alcohol with 1 5 molecules of solvent of crystallisation, which can be removed at 110° C. It gives the iodoform test with iodine in aqueous sodium hydroxide. At 260° to 265° C. it decomposes. It is insoluble in w ater, but dissolves in hot alcohol or aqueous sodium hydroxide. Alcoholic ferric chloride gives a faint olive-green tint concentrated sulphuric acid gives no coloration in the cold, but on warming an olive-green tint appears, changing to deep red. The chloride may be converted to the oodde in the usual manner. 

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