Iodine tris , reactions with

Trimethylarsine gives a 98% yield of trimethylarsine difluoride when treated with xenon difluoride [102] in fluorotrichloromelhane. and tnsfpentafluorophen-yl)arsine gives a 94% yield of tris(pentafluornphenyl)arsme difluoride after reaction with dilute fluorine in fluorotnchloromethane at 0 C [106] Other trivalent arsenic compounds have also been fluorinated with xenon difluoride [103] In addition, arsines have been oxidatively fluorinated by iodine pentafluoride [107] or electrochemically in 26-34% yield [108]... 

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. ... 

Estimation of the Binding Site. Tryptophan-108 shows a specific reaction with iodine, distinguishing it from other tryptophan residues of lysoz3mie. When try-108 is selectively oxidized by iodine, lysozyme completely loses its activity. Nevertheless, the lysozyme still shows the ability to form an enzyme-substrate complex with CM-chitin. This observation contributes to the conclusion that try-62 is an essential binding site for a complex formation (13). All ozonized lysozymes formed strong complexes with CM-chitin and could only be eluted by 0.2N HA (Fig. 6). This further confirms that two tryptophan residues (108 and 111) are indispensible for the hydrolytic action of lysozyme, and that inactivation by ozone cannot be attributed to inhibition of substrate binding capability. 

If one tries to transfer carbanions to halogen compounds by reacting with elementary halogen oxidative coupling often is the main reaction. Better results are observed with carbontetrachloride, carbontetrabromide, or other polyhaloalkenes as reagents l As a good alternative we offer the reaction with diphenylarsanechloride and then with bromine, iodine, or sulfurylchloride as has been demonstrated by the example shown in Scheme 27. 

Electrophilic addition to 9-vinylcarbazole occurs in the Markovnikov sense, thus hydrogen chloride,hydrogen bromide,chlorine, and bromine in carbon tetrachloride, and iodine chloride in pyridine are recorded as adding with initial electrophilic attack at the methylene. Mercuric acetate in methanol gave 9-(2-acetoxymercuri-l-methoxyethyl)carbazole. Although 9-vinylcarbazole gave an iodohydrin, comparable reaction with methanolic sodium hypochlorite led to 9-(2-chlorovinyl)carbazole. Catalytic reduction of the latter produced 9-(2-chloroethyl)carbazole. Tri-phenyltin hydride gave 96. ... 

According to C. F. Barwald and A. Monheim (1835), the decomposition is accelerated by the presence of organic substances. J. Milbauer tried the effect of thirty-two metal chlorides of sodium tungstate and molybdate of uranyl sulphate and of sulphuric, selenic, arsenic, and boric acids on the photo-decomposition of chlorine water, and found. that none accelerated but that most retarded the action. Chlorine catalyzes the decomposition of bromine water and bromine, chlorine water while iodine does not accelerate, but rather retards the reaction, probably by forming relatively stable iodine compounds. A. Bcnrath and H. Tuchel found the temp, coeff. of the velocity of the reaction with chlorine water between 5° and 30° increases in the ratio 1 1 395 per 10°. 

When treated with iodine pentafluoride, triphenylbismuthane gives triphenylbismuth difluoride but no evidence for the formation of bismuth(V) derivatives was found in the reactions with tris(4-fluorophenyl)bismuthane and tris(trifluoromethyl)bismuthane. Fluorine-aryl (or alkyl) exchange takes place in these cases instead of oxidative fluorination.139140... 

When the pure gas is passed through a saturated solution of barium hydroxide or copper sulphate, no opalescence or precipitate is produced for at least half a minute if any carbon dioxide is present, however, the solution becomes milky at once. According to Weeldenburg2 there is no reaction between carbonyl sulphide and copper sulphate in neutral or acid solution, nor is there any reaction with iodine or ethereal tri-ethylphosphine (qf. CS2, p. 263). 

Note that the product formed by reaction with pyridine (reaction c) contains the tri-iodide ion, also present in solutions containing both iodine and potassium iodide thus, solutions of iodine in pyridine and iodine in aqueous KI have about the same color. 

The assay mixture contained GTP, EDTA, KC1, 10% glycerol, Tris-HCl (pH 7.8), and hydrolase. The reaction was incubated at 37°C for 90 minutes in the dark and was terminated by the addition of 1 M HO containing 1% iodine and 2% KI. After 30 minutes, proteins were removed by centrifugation and excess iodine was removed with ascorbic acid. Samples were injected for analysis. Figure 9.134 shows the results of an assay, while Figure 9.135 shows the activity in a homogenate as a function of incubation time. 

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