Chloride anion, addition

The lithium chloride-catalyzed addition of 2-phenylthiirane to diphenylketene may involve attack on carbon by chloride ion followed by addition of the anion of 2-chloro-l-phenylethanethiol to the ketene, but no data about the mechanism were given (69TL259). 

Dehydration of prednisolone acetate (175b) yields the corresponding 9,11 olefin. As a variation on the chemistry we have seen previously, this olefin is allowed to react with chlorine in the presence of lithium chloride. If this addition is assumed to proceed by the customary mechanism, the first intermediate should be the 9a,11a-chioronium ion. Axial attack by chloride anion from the 110 position will lead to the observed stereochemistry of the product dichlorisone (240). ... 

The film-destructive anions are CF, T, CIO4, SO4, etc. for iron electrodes and in addition to these ions, NOJ, SCN , etc. for aluminum electrodes.19 In many cases, the film-destructive anions are the anions of strong acids the most well-known and studied anion is the chloride anion. 

Both these conversion processes involve the addition of electrons to the toxic substances. The trichloroethylene molecule is electrically neutral and must gain electrons in reactions that generate negatively charged chloride anions, hi addition, water or hydronium ions must supply hydrogen atoms that replace the chlorine atoms in the organic substance. The detailed reaction is complicated, but the net reaction is relatively simple CI2 C I CHCl + 3 H3 + 6 H2 C CH2 + 3 Cr + 3 H2 O... 

Kostic et al. recently reported the use of various palladium(II) aqua complexes as catalysts for the hydration of nitriles.456 crossrefil. 34 Reactivity of coordination These complexes, some of which are shown in Figure 36, also catalyze hydrolytic cleavage of peptides, decomposition of urea to carbon dioxide and ammonia, and alcoholysis of urea to ammonia and various carbamate esters.420-424, 427,429,456,457 Qggj-jy palladium(II) aqua complexes are versatile catalysts for hydrolytic reactions. Their catalytic properties arise from the presence of labile water or other solvent ligands which can be displaced by a substrate. In many cases the coordinated substrate becomes activated toward nucleophilic additions of water/hydroxide or alcohols. New palladium(II) complexes cis-[Pd(dtod)Cl2] and c - Pd(dtod)(sol)2]2+ contain the bidentate ligand 3,6-dithiaoctane-l,8-diol (dtod) and unidentate ligands, chloride anions, or the solvent (sol) molecules. The latter complex is an efficient catalyst for the hydration and methanolysis of nitriles, reactions shown in Equation (3) 435... 

To determine if CP was indeed lost in the chemical step the potential was held at — 1.7 V for 30s, then a positive-going scan initiated up to 1.5 V. A number of anodic peaks were observed with the largest and most significant at 1.2 V. This was unequivocally attributed to the oxidation of CP to Cl2 on the basis of a second experiment in which tetrabutylammonium chloride was added to the base electrolyte and the potential regime repeated. Hence, the chemical step after the addition of the first electron involves the ejection of the chloride anion. The identity of the species formed subsequent to this process was determined thus O Toole et al. prepared and characterised the hydrido and acetonitrile complexes (as the bipyridine derivatives) and determined their E° values as —1.46 V and —1.25 V, respectively, far removed from the observed value — 1.62 V hence neither of these species were taken as being the product. 

Anions such as sulphate and phosphate form involatile salts with metal ions and reduce the reading of the sample solution. These anions may be removed by the addition of lanthanum chloride which precipitates them out and replaces them with the chloride anion. 

It was presumed that the third product (26) results from elimination of the elements of hydrogen chloride, in addition to deacetylation, by the strong base, to give a 2-hydroxy-D-glucal (1,5-anhydro-D-arabino-hex-l-enitol) anion (27) which then adds phenyllithium... 

The compound [Al(Salen)(H20)2]Cl is not air-sensitive. It has mp 162-165°C dec. The cation is soluble only in water. IR (KBr) 3057 s (br) 1639 s, 1560 m, 1473 s, 1296 s, 814 m, 760 s cm . The synthesis and properties of the SalenCl and Acen derivatives are described in Ref. 7. Salophen, Salen( Bu), Salpen( Bu), Salben( Bu), Salophen Bu, and Salomphen Bu derivatives can also be prepared in a similar manner. In the solid state these compounds have been shown by X-ray crystallography to contain six-coordinate octahedral aluminum. The solvent molecules are trans to one another and the hgand copla-nar with the aluminum atom. The chloride anions are connected by hydrogen bonds to the solvents on the aluminum as well as additional solvent in the crystal lattice. 

Interestingly, the bis-urea pocket represents also a good host for anions and, indeed, upon the addition of ammonium chloride the pocket is occupied with the chloride anion. The binding pocket can change the reactivity ofthe metal center as it facilitates substitution processes at the palladium center. Upon the introduction of... 

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