Iodosobenzene, with sodium

Iodoxybenzene has been prepared by the disproportionation of iodosobenzene,4Hi by oxidation of iodosobenzene with hypo-chlorous add or bleaching powder,7 and by oxidation of iodobenzene with hypochlorous acid or with sodium hydroxide and bromine.8 Other oxidizing agents used with iodobenzene include air,3 chlorine in pyridine,9 Caro s acid,19-11 concentrated chloric acid,15 and peracetic acid solution.13 Hypochlorite oxidation of iodobenzene dichloride has also been employed.14... 

Two azido groups can be added to double bonds by treatment with sodium azide and iodosobenzene in acetic acid." ... 

The epoxidation of simple olefins which cannot benefit from secondary interactions brings some formidable problems that were solved by sophisticated catalyst design, mainly by the groups of Jacobsen and Katsuki in the 1990 s. A class of square planar salen complexes was chosen (Figure 19, for example) capable of giving a metal-oxo derivative by reaction with monooxygen donors such as iodosobenzene or sodium hypochlorite (the preferred oxidant). A series... 

Table 3. 1,2-Diazides by Reaction with Sodium Azide and Iodosobenzene in Acetic Acid76...

Iodosobenzene.—Phenyl iodochloride (2 g.) is thoroughly ground in a mortar with 3 Y-sodium hydroxide solution (10 c.c.). After the mixture has stood over night the resultant iodosobenzene is collected at the pump, washed with water, and dried on porous plate. The substance is not crystalline. 

To a solution of iodosobenzene (2.2 g, 10 mmol) and 5 (1.79 g, 5 mmol) in acetic acid (30 ml) sodium azide (2.3 g, 35 mmol) was added. The mixture was maintained at room temperature for 10 min then kept at 50 °C for 3 hours, then poured into water (200 ml) and extracted with chloroform (4 x 50 ml). The combined extracts were washed with water (2 x 100 ml), dried mgS04), and evaporated. The residue was chromatographed on silica gel (60 mesh) elution with benzene-pet. -ether (1 1) 6 (1.27 g, 64%). 

Polymer supported sodium ruthenate is able to catalyze the oxidation of alcohols with iodosobenzene or tetrabutylammonium periodate in CH2CI2.8 It is not clear whether the primary oxidant is ruthenate or perruthenate. 

The following procedure is used in the analysis of iodoso and iodoxy compounds. In a 200-cc. iodine flask are placed 100 cc. of water, 10 cc. of 6 N sulfuric acid, 2 g. of iodate-free potassium iodide, 10 cc. of chloroform, and finally the sample, about 0.25 g. The flask is shaken for fifteen minutes (or longer, if the reaction is not complete), and then the mixture is titrated with 0.1 N sodium thiosulfate. If the sample is pure the change of color in the chloroform layer may be taken as the end point, but if impurities are present starch must be used, for the impurities impart a brownish color to the chloroform. This solvent is desirable, as it facilitates the reaction with potassium iodide by dissolving the reaction products. Iodosobenzene may be differentiated from iodoxybenzene, for the former reduces iodide ion in a saturated sodium borate solution, whereas the latter does not.1 The reactions involved are ... 

The reaction of alkenes with iodosobenzene in acetic acid in the presence of sodium azide offers a simple and high yield route to 1,2-diazides (Table 3)76. a-Azido ketones are side products or the exclusive product from the reaction with conjugated alkenes. Allylic azides or oxonitriles, resulting from oxidative cleavage of the C-C double bond, are alternatively obtained from trisubstituted steroid alkenes77. 

The direct azido phenylselenenylation of alkenes can be accomplished by four different methods A126 reaction with phenylselenenyl chloride and sodium azide in dimethyl sulfoxide or dimethylformamide B127 reaction with diphenyldiselenide, sodium azide and iodosobenzene diacetate in dichloromethane C128 reaction with iV-phenylselenophthalimide (TV-PSP) and azidotrimethylsilane in dichloromethane D128 as in C but in the presence of 0.1 equivalent of tetrabutylammonium fluoride. 

Diarylacetylenes are converted in 55-90% yields into a-diketones by refluxing for 2-7 h with thallium trinitrate in glyme solutions containing perchloric acid [413. Other oxidants capable of achieving the same oxidation are ozone [84], selenium dioxide [509], zinc dichromate [660], molybdenum peroxo complex with HMPA [534], potassium permanganate in buffered solutions [848, 856, 864,1117], zinc permanganate [898], osmium tetroxide with potassium chlorate [717], ruthenium tetroxide and sodium hypochlorite or periodate [938], dimethyl sulfoxide and iV-bromosuccin-imide [997], and iodosobenzene in the presence of a ruthenium catalyst [787] (equation 143). 

Preparation. The reagent is prepared by stirring iodosobenzene diacetate with iN sodium hydroxide, collecting and drying the solid, and macerating it with chloroform to remove a little iodobenzene. This procedure is preferable to an older one involving alkaline hydrolysis of iodosobenzene dichloride because iodoso-... 

Diphenyliodonium iodide can be prepared by stirring a mixture of 0.1 mole each of iodosobenzene and iodoxybenzene with I N sodium hydroxide for 24 hrs. The... 

Experiment The iodochloride is carefully triturated with dilute caustic soda in a mortar (for 1 gramme of the iodochloride, use a solution of 0.5 gramme sodium hydroxide ill 4 grammes of water), and allowed to stand over night. The iodosobenzene is then filtered off, washed with water, and pressed out on a porous plate. 

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