Iodoxybenzene preparation

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... 

This one-step method of preparing iodoxybenzene is preferable to earlier methods because it is simpler and the yield is substantially higher. The procedure seems general for iodoxyarenes,... 

Iodoxybenzene.—The major portion of the iodosobenzene so prepared is made into a paste with a little water and submitted to steam distillation in a round-bottomed flask. The distillation is continued until all the material has dissolved and the iodobenzene produced has passed over (use a condenser and receiver). The residue after the distillation (if still turbid) is filtered while hot and the filtrate is concentrated on the water bath until a sample, poured... 

For use in the preparation of iodoxybenzene by the disproportionation method (p. 72) it is superfluous to dry the crude product and to wash it with chloroform to remove iodobenzene. The crude wet iodosobenzene may also be used directly for the preparation of diphenyliodonium iodide (p. 52), but it is desirable to assay the wet product by titration to determine the quantity of iodoxybenzene needed. 

Iodoxybenzene has been prepared by oxidizing iodobenzene with Caro s acid 2 by treating iodobenzene with hypochlorous acid or with aqueous sodium hydroxide and bromine 3 by action of chlorine upon iodobenzene dissolved in pyridine 4 by oxidation... 

In a 2-1. round-bottomed flask equipped with an efficient mechanical stirrer (Note 1) are placed 110 g. (0.4 mole) of freshly prepared, pulverized iodobenzene dichloride (jp. 69) (Note 2), 1.0 mole of sodium hypochlorite solution (Note 3), and 2 cc. of glacial acetic acid. The vigorously stirred mixture is heated on a water bath maintained at 65-75°. After ten to fifteen minutes the heated mixture becomes frothy and the yellow color of iodobenzene dichloride is displaced by the white color of iodoxybenzene. The stirring is stopped after one hour, and the flask is cooled in an ice bath. The product is filtered with suction,... 

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... 

The biocatalytic oxidation of racemic 0,5-dimethyl O-p-nitrophenyl phosphor-odithioate (5// )-288 catalyzed by chloroperoxidase from Caldariomyces fumago led to the formation of the corresponding (—)-(5)-thiophosphate 289 and unoxidized substrate (+)-(/ )-288. The thionoester (5// )-288 was subjected to oxidation with hydrogen peroxide in the presence of chloroperoxidase (CPO) in a mixture of citrate buffer, pH 5, and ethanol. Both compounds were prepared with 99.6% and 97% ee, respectively. The thicmation of the ( )-(5)-phosphate 289 with Lawesson s reagent gave (—)-(5)-phosphorodithioate 288 with full stereospecificity, while the oxidation of unreacted substrate (+)-(/ )-288 with iodoxybenzene resulted in the formation of (-i-)-(/ )-289 with 94.9% ee (Scheme 95) [192]. 

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