Iodoso compounds

Iodobenzene and some Related Compounds.—Aromatic iodo-compounds containing iodine in the nucleus unite with two atoms of chlorine to form iodochlorides (Preparation 469), the iodine becoming trivalent. Caustic soda converts the latter into iodoso-compounds, oxygen replacing the two chlorine atoms (Preparation 465.)... 

Iodoso-compounds behave as diacid bases, e.g., C6H5I(OH)2, which combine with acids to form salts (Preparation 466). Reducing agents or... 

Iodobenzene [591-50-4], C6HBI, mol wt 204.02, 62.23% I, mp —30°C, bp 188—189°C, is a colodess liquid that rapidly becomes yellow and has a characteristic odor. It is insoluble in water, but completely miscible with alcohol, chloroform, and ether. It has a density of 1.832 g/mL at 20°C and a refractive index of 1.621 at 4°C. Iodobenzene is prepared by the reaction of iodine and benzene in the presence of an oxidizing agent and from benzeneiazonium sulfate and potassium iodide (122). Iodobenzene is used as a heavy liquid for refractive index determinations, but probably its principal use is in the synthesis of iodoso compounds, RIO iodoxy compounds, RI02 and iodonium salts, R IX. 

Trivalent iodine compounds can be divided into the following categories (1) with one carbon-iodine bond, such as in iodo salts, RIX2, and iodoso compounds, RIO (2) with two carbon-iodine bonds on the same iodine, such as RRTX and (3) with three carbon-iodine bonds on the same iodine, such as Phsl. 

Dissolving an ArICh in basic solution forms the iodoso compound, ArlO (equation 128). Another synthetic procedure to obtain iodoso compounds is by direct oxidation of Arl with ozone, fuming nitric acid, or KMn04. 

Oxidation of p - iodophenylarsinic acid, or the iodoso - compound by chlorine in cooled sodium hydroxide solution, gives the iodoxy-derivative ... 

Phenyl lodonium Hydroxide.—These iodoso compounds are derivatives of the hypothetical base, CeHs—I(0H)2, phenyl iodonium hydroxide. When a solution of iodoso benzene is heated it decomposes as follows ... 

Among other oxidizing agents that have been used to accomplish the conversion of ArCH3 to ArCHO are ceric ammonium nitrate, ceric trifluoroacetate, hyperva-lent iodoso compounds (see 19-3), urea-H202 with micrwoave irradiation, and silver(II) oxide. Oxidation of ArCHa to carboxylic acids is considered at 19-11. 

The spectrum of applications of potassium permanganate is very broad. This reagent is used for dehydrogenative coupling [570], hydrox-ylates tertiary carbons to form hydroxy compounds [550,831], hydroxylates double bonds to form vicinal diols [707, 296, 555, 577], oxidizes alkenes to a-diketones [560, 567], cleaves double bonds to form carbonyl compounds [840, 842, 552] or carboxylic acids [765, 841, 843, 845, 852, 869, 872, 873, 874], and converts acetylenes into dicarbonyl compounds [848, 856, 864] or carboxylic acids [843, 864], Aromatic rings are degraded to carboxylic acids [575, 576], and side chains in aromatic compounds are oxidized to ketones [566, 577] or carboxylic acids [503, 878, 879, 880, 881, 882, 555]. Primary alcohols [884] and aldehydes [749, 868, 555] are converted into carboxylic acids, secondary alcohols into ketones [749, 839, 844, 863, 865, 886, 887], ketones into keto acids [555, 559, 590] or acids [559, 597], ethers into esters [555], and amines into amides [854, 555] or imines [557], Aromatic amines are oxidized to nitro compounds [755, 559, 592], aliphatic nitro compounds to ketones [562, 567], sulfides to sulfones [846], selenides to selenones [525], and iodo compounds to iodoso compounds [595]. 

If caustic soda is allowed to act on an iodochloride, the two chlorine atoms are replaced by one oxygen atom, and an iodoso-compound is obtained ... 

The iodoso-compounds have the power of uniting with adds to form... 

The iodoso-compounds, on treatment with hydriodic acid, are reduced to iodides, with a separation of iodine. 

If an iodoso-compound is heated carefully to ioo°,-it passes over to an iodite (Jodcruerbin dung) ... 

The same compound may also be obtained by treating an iodoso-compound with steam. 

The iodites, like the iodoso-compounds, puff up and suddenly decompose on heating. (Try it.) They also abstract iodine from hydriodic add, and in double the quantity as compared to the similar action of the iodoso-compounds. 

Iodoxy compounds and iodides from iodoso compounds... 

An intensive study on the reaction mechanism revealed that the allylic iodoso compound (67), initially formed with 1 equiv. of peracid, rearranges to an unstable allylic hypoiodide (68) in a [2,3] sigmatropic manner. The intermediate... 

Sulfuric acid lodonium salts from iodoso compounds lodonium betaines s. 19, 634 H2SO4... 

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