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Salts, acid complex

CH2CI-CO-CH3. Colourless lachrymatory liquid b.p. 119°C. Manufactured by treating propanone with bleaching powder or chlorine. It is used as a tear gas and is usually mixed with the more potent bromoacetone. chloro acids Complex chloroanions are formed by most elements of the periodic table by solution of oxides or chlorides in concentrated hydrochloric acid. Potassium salts are precipitated from solution when potassium chloride is added to a solution of the chloro acid, the free acids are generally unstable. [Pg.93]

Lewis Acid Complexes. Sulfolane complexes with Lewis acids, such as boron trifluoride or phosphoms pentafluoride (17). For example, at room temperature, sulfolane and boron trifluoride combine in a 1 1 mole ratio with the evolution of heat to give a white, hygroscopic soHd which melts at 37°C. The reaction of sulfolane with methyl fluoride and antimony pentafluoride inhquid sulfur dioxide gives crystalline tetrahydro-l-methoxythiophenium-l-oxidehexafluoroantimonate, the first example of an alkoxysulfoxonium salt (18). [Pg.69]

In sulfamation, also termed A/-sulfonation, compounds of the general stmcture R2NSO2H are formed as well as their corresponding salts, acid hahdes, and esters. The reagents are sulfamic acid (amido—sulfuric acid), SO —pyridine complex, SO —tertiary amine complexes, ahphatic amine—SO. adducts, and chlorine isocyanate—SO complexes (3). [Pg.74]

OC-Hydroxycarboxylic Acid Complexes. Water-soluble titanium lactate complexes can be prepared by reactions of an aqueous solution of a titanium salt, such as TiCl, titanyl sulfate, or titanyl nitrate, with calcium, strontium, or barium lactate. The insoluble metal sulfate is filtered off and the filtrate neutralized using an alkaline metal hydroxide or carbonate, ammonium hydroxide, amine, or alkanolamine (78,79). Similar solutions of titanium lactate, malate, tartrate, and citrate can be produced by hydrolyzation of titanium salts, such as TiCl, in strongly (>pH 10) alkaline water isolation of the... [Pg.145]

Alcohols react with boric acid with elimination of water to form borate esters, B(OR)3. A wide variety of borate salts and complexes have been prepared by the reaction of boric acid and inorganic bases, amines, and heavy-metal cations or oxyanions (44,45). Fusion with metal oxides yields... [Pg.193]

Metal impurities can be determined qualitatively and quantitatively by atomic absorption spectroscopy and the required purification procedures can be formulated. Metal impurities in organic compounds are usually in the form of ionic salts or complexes with organic compounds and very rarely in the form of free metal. If they are present in the latter form then they can be removed by crystallising the organic compound (whereby the insoluble metal can be removed by filtration), or by distillation in which case the metal remains behind with the residue in the distilling flask. If the impurities are in the ionic or complex forms, then extraction of the organic compound in a suitable organic solvent with aqueous acidic or alkaline solutions will reduce their concentration to acceptable levels. [Pg.53]

The formation of acyl halide-Lewis acid complexes have been observed by several methods. For example, both 1 1 and 1 2 complexes of acetyl chloride, with AICI3 can be observed by NMR spectroscopy. The existence of acylium ions has been demonstrated by X-ray diffraction studies on crystalline salts. For example, crystal structure determinations have been reported for /i-methylphenylacylium and acetylium ions as SbFg salts. There is also a good deal of evidence from NMR measurements which demonstrates that acylium ions can exist in nonnucleophilic solvents. " The positive charge on acylium ions is delocalized onto the oxygen atom. This delocalization is demonstrated in particular by the short O—C bond lengths in acylium ions, which imply a major contribution from the structure having a triple bond ... [Pg.584]

The observed complexity of the Se(IV) electrochemistry due to adsorption layers, formation of surface compounds, coupled chemical reactions, lack of electroactivity of reduction products, and other interrelated factors has been discussed extensively. Zuman and Somer [31] have provided a thorough literature-based review with almost 170 references on the complex polarographic and voltammetric behavior of Se(-i-IV) (selenous acid), including the acid-base properties, salt and complex formation, chemical reduction and reaction with organic and inorganic... [Pg.70]

In an earlier series of experiments, Cullis and Ladbury examined the kinetics of the permanganate oxidation of hydrocarbons in acetic acid solution. Initial attack on toluene occurs at the methyl group and a total order of two was found. Electron-withdrawing agents reduced the rate of oxidation. However, the effects of added salts were complex and the authors believe that lower oxidation states of manganese are responsible for the oxidation. The oxidation of ethylbenzene produced acetophenone, the process being second-order with... [Pg.298]

The rhodium-catalyzed conversion of a-diazo-p-hydroxy carbonyl into P-dicarbonyl compounds (Table 23, Entries 6-8) in general seems to be preferable to the acid-catalyzed reaction because of higher yields and absence of side-reactions 37S,377). From a screening of 20 metal salts and complexes, Rh2(OAc)4, RhCl(PPh3)3, PdCl2 and CoCl2 emerged as the most efficient catalysts for the transformation of a-diazo-P-hydroxy esters into P-ketoesters 376). This reaction has become part of... [Pg.226]

Diselenophosphates have been much less investigated than the analogous dithiophosphates, but some interesting chemistry was revealed. The reactions of phosphorus(V) selenide, P2Se5, with alcohols and phenols produce diseleno-phosphoric acid diesters, (RO)2P(Se)SeH, the parent compounds of di-selenophosphato anionic ligands. The free acids are not stable and should be immediately converted to metal salts or complexes. [Pg.619]

Nothing has been found in the published literature about what takes place during the induction period. We believe that an active catalytic species is formed during this period, and that its formation requires reduction of chloroplatinic acid, or of whatever transition metal salt or complex one uses. [Pg.409]

Crystal structures are available for many (N)4Co-amino acid complexes (Table I). Many of the diastereomers (AS, AS) in the bis-en series have been resolved using classic crystallization (usually via bromocamphor sulfonate, arsenyl-, or antimonyl-tartrate salts) or ion exchange methods (Table II). Reversed-phase ion-pair HPLC, using aryl phosphate or aryl/alkyl sulfonate ion pairing reagents in MeOH/ H20 eluent, has allowed diastereomer separations to be carried out on analytical amounts (28) (Table II). [Pg.315]

In practice iodide salts of the amino acid complexes are used, as I is lost as Mel under conditions of excess alkylating agent. [Pg.316]

Two types of insoluble triarylcarbonium compounds are used industrially as pigments. Both are salts of these basic dyes. So-called Alkali Blue type triarylcarbonium pigments are inner salts of sulfonic acids, while the second group comprises salts of complex inorganic anions of heteropolyacids. [Pg.541]

Consider using polyvinyl pyrrolidone (PVP), which is widely used because of its biological compatibility, low toxicity, high complexing power, and its inert behavior toward salts, acids, and thermal degradation [21]. [Pg.255]

The triphenylmethyl ion is also, very probably, present in the orange-yellow products of the salt and complex salt type which are produced from triphenylcarbinol with concentrated sulphuric acid and from triphenylchloromethane with metallic chlorides (ZnCl2, A1C13, SnCl4, SbCl6). [Pg.355]

Triethylammonium formate-formic acid complex, (HC02NHEtj)2(HC02H)3, is used in a one-pot reductive aldol condensation of Meldrum s acid with aldehydes to produce the alkylated derivative [51]. Although feasible, the process has not been adapted for use with a quaternary ammonium formate salt. [Pg.268]

Block copolymers of (R,S)-(3-butyrolactone and eCL have been synthesized by combining the anionic ROP of the first monomer with the coordinative ROP of the second one (Scheme 15) [71]. The first step consisted of the synthesis of hydroxy-terminated atactic P(3BL by anionic polymerization initiated by the alkali-metal salt of a hydroxycarboxylic acid complexed with a crown ether. The hydroxyl end group of P(3BL could then be reacted with AlEt3 to form a macroinitiator for the eCL ROP. [Pg.24]

Reactions of dithiophosphoric acids and their salts with complexes are also employed to prepare dithiophosphate complexes, e.g.,... [Pg.76]

Diselenophosphate complexes are prepared from the interaction of metal salts and complexes with appropriate diselenophosphoric acid or its salt. The acids are obtained from the reaction of phosphorus(V) selenide with alcohols 229). The preparation of phosphorus(V) selenide and its reactions with alcohols 229) and amines 22°) have been described and a variety of complexes reported (Table 4). The biological activity of these compounds does not seem to have described but the exercise of extreme caution when handling these materials is recommended. Zingaro and his coworkers 229-232) thoroughly characterized the thermal and spectroscopic properties of a number of compounds. [Pg.77]

Osmium tetroxide is obtained as an intermediate during recovery of osmium metal from osmiridium or other noble metal minerals (See Osmium). In general, oxidation of an aqueous solution of an osmium salt or complex, such as sodium osmate with nitric acid, yields the volatile tetroxide which may be distilled out from the solution. In the laboratory, the compound can be prepared by oxidation of the osmium tetrachloride, OsCh, or other halide solutions with sodium hypochlorite followed by distdlation. [Pg.672]


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See also in sourсe #XX -- [ Pg.104 , Pg.112 ]




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Acid-Complexed Metal Salts

Alkali metal complexes acid salts

Complex salts

Salt complexation

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