Thiocyanates nitrate

Displacement by cyanide works particularly well, and many other nucleophilic substitution reactions are enhanced by PTC. Most monovalent anions can be transferred, including alkoxides, phenoxides, thiocyanates, nitrates, nitrites, superoxides and all of the halides. Divalent anions are usually too hydrophilic to be transferred into the organic phase. 

The reactions of lanthanide thiocyanates, nitrates, and chlorides with TPPO have been studied by Cousins and Hart (202, 203, 205). The reactions of lanthanide nitrates with TPPO in ethanol, acetone, ethylacetate and tetrahydrofuran are given in Fig. 1. The nature of the complexes isolated depends on the concentrations of the ligand and the metal ion, temperature of mixing, presence or absence of the seed of the desired complex, size of the cation, and the nature of the solvent. Tetrakis-TPPO complexes of Ce(III) and Nd(III) perchlorates have been reported (206, 207). Two of the perchlorates are coordinated to the metal ion in these complexes. 

By contrast, the catalytic site responsible for the halogenation, hydroxylation, and other (two-electron) oxygenation reactions has been better, although not completely, characterized by X-ray crystallography of CPO complexed with several substrates (such as iodide/bromide and cyclopentane-1,3-dione) and other compounds (such as carbon monoxide, thiocyanate, nitrate, acetate, formate and, in a ternary complex, with dimethylsulfoxide and cyanide) [88, 90]. The above substrates bind at the distal side of heme, and the corresponding structures were also useful to establish the mechanism of Compound I formation as discussed above [90]. 

The thiolates, though less sensitive to basicity, are more reactive than oxygen anions over the total accessible range of basicity, but intersect the amine line at ca. pA 12. Other reactive nucleophiles which do not fall in the amine, thiolate, or oxygen anion categories are fluoride, thiosulfate, nitrite, azide, and sulfite. Halides other than fluoride, and also thiocyanate, nitrate, sulfate, and thiourea have no reactivity towards p-nitrophenyl acetate (Jencks and Carriuolo, 1960a). The total lack of reactivity of thiocyanate, iodide, bromide, and thiourea, all very polarizable nucleophiles which are reactive to sp carbon, rules out any possibility that polarizability is at all important in nucleophilic reactions at the carbonyl carbon. In general, the order of nucleophilic reactivity to p-nitrophenyl acetate correlates well with nucleophilic reactivity to other carboxylic acid derivatives (see later). Nitrite, however, shows... 

Thiocyanate, nitrate, and fluoride interfere in this method for determining rhenium. Palladium and copper in acid media sparingly soluble a-furildioximates. Normally, rhenium should be separated from Mo before the determination. 

Using this constant ion concentration method. Van Amelsvoort et al. [12] measured the relative anion sensitivity of the enzyme from rabbit gastric mucosa for 13 different anions (Table 2). Of these anions sulfite was the maximally stimulating anion, followed by oxalate and bicarbonate. Besides thiocyanate, nitrate and perchlorate and particularly azide are also inhibitory anions relative to chloride. 

Blount, B. C. Valentin-Blasini, L. (2006). Analysis Of Perchlorate, Thiocyanate, Nitrate And Iodide In Human Amniotic Fluid Using Ion Chromatography And Electrospray Tandem Mass Spectrometry. Analytica Chimica Acta, Vol.567, No.l, pp 87-93, ISSN 0003-2670... 

The simple ion transfer across ITIES was observed with alkali metal ions, tetraalkyl-ammonium cations, choline, acetylcholine, picrate, perchlorate, iodide, thiocyanate, nitrate, dodecylsulphate, cationic forms of various tetracycline derivatives, etc. The facilitated ion transfer was mainly studied with alkah and alkaline earth metal ions the transfer of which was mediated by ionophores already mentioned in the first section of this lecture (for reviews see [13,18]). 

In the former, it gives precipitates with halides (except the fluoride), cyanides, thiocyanates, chromates(VI), phosphate(V), and most ions of organic acids. The silver salts of organic acids are obtained as white precipitates on adding silver nitrate to a neutral solution of the acid. These silver salts on ignition leave silver. When this reaction is carried out quantitatively, it provides a means of determining the basicity of the acid... 

Silver nitrate is used volumetrically to estimate chloride, bromide, cyanide and thiocyanate ions. Potassium chromate or fluorescein is used as an indicator. 

Pheiiyl iso-thiocyanate may be prepared in quantity directly from aniline. Aniline, carbon disulphide and concentrated aqueous ammonia react to form the sparingly soluble ammonium phenyldithiocarbamate this is decomposed by lead nitrate to produce phenyl iso-thiocyanate ... 

Sulfonation by oleum occurs as expected on C-5 (598). The same position is reactive toward bromination, thiocyanation, and nitration... 

Nitration, bromination, and thiocyanation of several 4-substituted 2-methylsulfonylthiazoles have been studied (213). 

Nitrates Aluminum, BP, cyanides, esters, phosphorus, tin(II) chloride, sodium hypophos-phite, thiocyanates... 

Thousands of compounds of the actinide elements have been prepared, and the properties of some of the important binary compounds are summarized in Table 8 (13,17,18,22). The binary compounds with carbon, boron, nitrogen, siUcon, and sulfur are not included these are of interest, however, because of their stabiUty at high temperatures. A large number of ternary compounds, including numerous oxyhaUdes, and more compHcated compounds have been synthesized and characterized. These include many intermediate (nonstoichiometric) oxides, and besides the nitrates, sulfates, peroxides, and carbonates, compounds such as phosphates, arsenates, cyanides, cyanates, thiocyanates, selenocyanates, sulfites, selenates, selenites, teUurates, tellurites, selenides, and teUurides. 

Basic Extractants. Only long-chain quaternary ammonium salts, R3NCH3 X , ia which R represents Cg—0 2 groups and X nitrate or thiocyanate, are effectively used for REE separations (see Quaternary ammonium compounds). The extractant reacts with REE according to an anion-exchange reaction ... 

Therefore the extent of extraction or back-extraction is governed by the concentration of X ia the aqueous phase, the distribution coefficients, and selectivities depending on the anion. In nitrate solutions, the distribution coefficient decreases as the atomic number of the REE increases, whereas ia thiocyanate solutions, the distribution coefficient roughly increases as the atomic number of the REE increases. The position of yttrium in the lanthanide series is not the same in nitrate and thiocyanate solutions, and this phenomenon has been used for high purity yttrium manufacture in the past. A combination of extraction by carboxyUc acids then by ammonium salts is also utilized for production of high purity yttrium. 

Analysis. The abiUty of silver ion to form sparingly soluble precipitates with many anions has been appHed to their quantitative deterrnination. Bromide, chloride, iodide, thiocyanate, and borate are determined by the titration of solutions containing these anions using standardized silver nitrate solutions in the presence of a suitable indicator. These titrations use fluorescein, tartrazine, rhodamine 6-G, and phenosafranine as indicators (50). 

Ana.lytica.1 Methods. Thiocyanate is quantitatively precipitated as silver thiocyanate, and thus can be conveniendy titrated with silver nitrate. In the presence of a ferric salt, a red-brown color, produced by the ferric thiocyanate compex, indicates the end point. 

Chloride. Chloride is common in freshwater because almost all chloride salts are very soluble in water. Its concentration is generally lO " to 10 M. Chloride can be titrated with mercuric nitrate. Diphenylcarbazone, which forms a purple complex with the excess mercuric ions at pH 2.3—2.8, is used as the indicator. The pH should be controlled to 0.1 pH unit. Bromide and iodide are the principal interferences, whereas chromate, ferric, and sulfite ions interfere at levels greater than 10 mg/L. Chloride can also be deterrnined by a colorimetric method based on the displacement of thiocyanate ion from mercuric thiocyanate by chloride ion. The Hberated SCN reacts with ferric ion to form the colored complex of ferric thiocyanate. The method is suitable for chloride concentrations from 10 to 10 M. 

A number of compounds of the types RBiY2 or R2BiY, where Y is an anionic group other than halogen, have been prepared by the reaction of a dihalo- or halobismuthine with a lithium, sodium, potassium, ammonium, silver, or lead alkoxide (120,121), amide (122,123), a2ide (124,125), carboxylate (121,126), cyanide (125,127), dithiocarbamate (128,129), mercaptide (130,131), nitrate (108), phenoxide (120), selenocyanate (125), silanolate (132), thiocyanate (125,127), or xanthate (133). Dialkyl- and diaryUialobismuthines can also be readily converted to secondary bismuthides by treatment with an alkali metal (50,105,134) ... 

Cadmium Hydroxide. Cd(OH)2 [21041-95-2] is best prepared by addition of cadmium nitrate solution to a boiling solution of sodium or potassium hydroxide. The crystals adopt the layered stmcture of Cdl2 there is contact between hydroxide ions of adjacent layers. Cd(OH)2 can be dehydrated to the oxide by gende heating to 200°C it absorbs CO2 from the air forming the basic carbonate. It is soluble ia dilute acids and solutions of ammonium ions, ferric chloride, alkah haUdes, cyanides, and thiocyanates forming complex ions. 

Cyanamide is precipitated by excess ammoniacal silver nitrate as disilver cyanamide [3384-87-0] which is dissolved in acid and titrated with thiocyanate solution (27). 

IQ. To determine the concentration of chloride ion, - a 5-mL aliquot of the methyl lithium solution is cautiously added to 25 ml of water and the resulting solution is acidified with concentrated sulfuric acid and then treated with 2-3 ml of ferric ammonium sulfate [Fe(NH4)( 04)2 12 H2O] indicator solution and 2-3 ml of benzyl alcohol. The resulting mixture is treated with 10.0 mL of standard aqueous 0.100 M silver nitrate solution and then titrated with standard aqueous 0.100 H potassium thiocyanate solution to a brownish-red endpoint. 

Fluoride < acetate < bicarbonate < hydroxide < formate < chloride < bromate < nitrite < cyanide < bromide < chromate < nitrate < iodide < thiocyanate < oxalate < sulfate < citrate. 

Guanidine Nitrate (Coll. Vol. i, 293) From ammonium thiocyanate, lead nitrate, and ammonia at 120°. Gockel, Z. angew. Chem. 48, 430 (1935). 

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