Iodine acetate iodate

Since silver salts are expensive, other cheaper reagents have been sought which can bring about the same type of conversion, and the iodine- tassium iodate- tassium acetate combination has been found to provide a useful alternative. Thallium(I) acetate may be used in place of silver acetate in the Woodward procedure, and syn hydroxylation of steroidal alkenes with dialliumflll) acetate in acetic acid has been performed. ... 

Procedure (iodometric method). Weigh out accurately about 5.0 g of the bleaching powder into a clean glass mortar. Add a little water, and rub the mixture to a smooth paste. Add a little more water, triturate with the pestle, allow the mixture to settle, and pour off the milky liquid into a 500 mL graduated flask. Grind the residue with a little more water, and repeat the operation until the whole of the sample has been transferred to the flask either in solution or in a state of very fine suspension, and the mortar washed quite clean. The flask is then filled to the mark with distilled water, well shaken, and 50.0 mL of the turbid liquid immediately withdrawn with a pipette. This is transferred to a 250 mL conical flask, 25 mL of water added, followed by 2 g of iodate-free potassium iodide (or 20 mL of a 10 per cent solution) and 10 mL of glacial acetic acid. Titrate the liberated iodine with standard 0.1M sodium thiosulphate. 

Iodine was determined by an iodometric titration adapted from White and Secor.(3) Instead of the normal Carius combustion, iodide was separated from the samples either by slurrying in 6M NaOH, or by stirring the sample with liquid sodium-potassium (NaK) alloy, followed by dissolving excess NaK in ethanol. Precipitated plutonium hydroxides were filtered. Iodine was determined in the filtrate by bromine oxidation to iodate in an acetate buffer solution, destruction of the excess bromine with formic acid, acidifying with SO, addition of excess KI solution, and titrating the liberated iodine with standard sodium thiosulfate. The precision of the iodine determination is estimated to be about 5% of the measured value, principally due to incomplete extraction of iodine from the sample. 

Vicinal iodo carboxylates may also be prepared from the reaction of olefins either with iodine and potassium iodate in acetic acid/ or with N-iodosuccinimide and a carboxylic acid in chloroform. " A number of new procedures for effecting the hydroxylation or acyloxylation of olefins in a manner similar to the Prevost or Woodward-Prevost reactions include the following iodo acetoxylation with iodine and potassium chlorate in acetic acid followed by acetolysis with potassium acetate reaction with iV-bromoacetamide and silver acetate in acetic acid reaction with thallium(III) acetate in acetic acid and reaction with iodine tris(trifluoroacetate) in pentane. ... 

Iodine water is added to an acetic acid sodium acetate buffered sample to reoxidise to iodate any iodine-containing substances produced by reduction of iodate by naturally occurring reducing substances present in the sample. Total iodate (i.e., iodate present in the original sample as iodate plus additional iodate produced by iodine water treatment) is then reacted with phenol solution at... 

Chlorine gas may be identified readdy by its distinctive color and odor. Its odor is perceptible at 3 ppm concentration in air. Chlorine may be measured in water at low ppm by various titrimetry or colorimetric techniques (APHA, AWWA and WEF. 1999. Standard Methods for the Examination of Water and Wastewater, 20th ed. Washington DC American Pubhc Health Association). In iodometric titrations aqueous samples are acidified with acetic acid followed by addition of potassium iodide. Dissolved chlorine liberates iodine which is titrated with a standard solution of sodium thiosulfate using starch indicator. At the endpoint of titration, the blue color of the starch solution disappears. Alternatively, a standardized solution of a reducing agent, such as thiosulfate or phenylarsine oxide, is added in excess to chlorinated water and the unreacted reductant is then back titrated against a standard solution of iodine or potassium iodate. In amperometric titration, which has a lower detection limit, the free chlorine is titrated against phenyl arsine oxide at a pH between 6.5 and 7.5. 

Potassium hydrogen phthalate Potassium hydrogen phthalate Potassium iodate Anhydrous sodium carbonate Zinc metal Standardisation of sodium hydroxide solution Standardisation of acetous perchloric acid Standardisation of sodium thiosulphate solution through generation of iodine Standardisation of hydrochloric acid Standardisation of EDTA solution... 

Cinnolin-4(l//)-one and its 6-chloro, 6-bromo, 6-nitro and 8-nitro derivatives react with sulfuryl chloride or bromine in acetic acid to give the corresponding 3-halo derivatives in about 20% yields. Iodination of 8-hydroxycinnolin-4(l//)-one with a mixture of potassium iodide and potassium iodate gives the 5,7-diiodo derivative the 6,8-diiodo derivative is formed from 5 -hydroxycinnolin-4( l//)-one. 

Oxidation of arylmethyl ketoximes by phenyliodoso diacetate in glacial acetic acid was second order overall, first order each in substrate and oxidant.145 Iodine allowed the oxidative dimerization of glycine ester enolates with low to moderate diastereoselec-tivity that is consistent with kinetic control.146 Although malonic acid is not oxidized by iodate under acidic conditions, oxidation proceeds in the presence of catalytic ruthenium(III). A mechanism is put forward to account for the observed orders of reaction.147 The rate of periodate oxidation of m-toluidine in acetone-water increases with ionic strength.148... 

P 35] A reaction system with two competitive parallel reactions was used for mixing characterization [36], The Dushman reaction involves the mixing of iodate, iodide and sodium acetate in one solution and a strong acid such as sulfuric acid or hydrochloric acid in another solution. If mixing is fast, the neutralization of the acid and the base dominates as the faster reaction. The redox reaction of iodide and iodate then is a slow process nearly no iodine is formed as the redox product... 

An earlier report51 that phenanthridone is brominated at C-2 on treatment with bromine in acetic acid has been confirmed291 chlorination (molecular chlorine) and iodination (iodine-iodate) in acetic acid give the corresponding 2-halogeno compounds in excellent yield.291 The bromination of 2-acetamidophenanthridone has also been described, although the orientation was not established with certainty.291... 

It was found impossible to measure the rate of decomposition by the evolution of gases because the release of these gas bubbles is very slow and erratic. The course of the reaction was followed by analyzing samples for the ammonium ion. Small amounts of the decomposing amalgam were forced through a capillary tube into a chilled solution of an iodate. The ammonium reacted with iodate ion to give iodide ion. The solution was then acidified with acetic acid and the iodine distilled out, collected and titrated with sodium thiosulfate. The method was checked with samples... 

The total amount of iodine present in the sample in all forms was thus determined. If bromide—bromate reagent with 2 N acetic acid and 0.05 N sulphuric acid was applied to the liberation of bound iodine, the result did not include tightly bound iodine, which can be released only by wet or dry ashing. With the omission of this step from the procedure, a result was obtained which represented iodide and free iodine only without the addition of iodate, free iodine only was determined. 

Potassium iodide solution iodine is liberated if a mineral acid is present. If acetic acid is used, no iodine separates even on long standing (difference from iodate). 

A reaction vessel was charged with potassium iodate (0.066 mol), iodine (0.132 mol), 700 ml of acetic acid, 50 ml of water, and 15 ml of sulfuric acid and then treated with the Step 1 product (0.132 mol) and refluxed for 8 hours. The purple solution was cooled to ambient temperature and treated with a 100 ml saturated solution of sodium thiosulphate. The beige-brown precipitate was collected by filtration, washed with 700 ml of water and 500 ml of ethanol, and dried. This solid was dissolved in 300 ml of hot hexanes and precipitated in 1.5 liter of ethanol. The precipitate was collected by filtration, washed with 1.0 liter ethanol, and dried the product was isolated in 92% yield as a white solid. 

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