Carbon organic solvents, instability

Tetrakis(phenyldifluorophosphine)nickel-(0) could also be obtained, using arsenic trifluoride in the presence of catalytic amounts of antimony pentachloride, or zinc fluoride as fluorinating agents. Yields as high as 50% could be obtained, but sizable decomposition on the process of fluorination of the chlorophosphine nickel-(0) complexes in solution could not be entirely suppressed. The marked instability of zerovalent nickel-phosphine complexes in solution in organic solvents, even under strictly anhydrous and anaerobic conditions, has been noted by several workers (16,20), but is still lacking a detailed explanation. A closer examination of the system carbon tetrachloride-tetrakis(trichlorophosphine)nickel-(0) (23) showed the main pa h of the reaction to consist in the formation of hexachloro-ethane with conversion of zerovalent into bivalent nickel, while the coordinated... 

Polyether antibiotics are hydrophobic compounds that are characterized chemically by their low polarities and their instability under acidic conditions. These antibiotics can be quantitatively extracted from the primary organic extract into carbon tetrachloride (393-395). When partitioning from a sodium chloride solution into an organic solvent, high yields have been achieved using dichloromethane (396, 397), carbon tetrachloride (391, 399), and chloroform (14, 398) as extraction solvents. In a different approach, water extracts containing lasalocid residues have been purified by partitioning into the mobile phase, which was a complex mixture of tetrahydrofuran, methanol, n-hexane, and ammonia (387, 389, 390, 392). To remove lipids, sample extracts have often been partitioned with n-hexane. 

Camosic acid is very unstable in the presence of aqueous solvents, but it is stable in nonpolar organic solvents. Curvelier et al. [26] have also observed the formation of several oxidation products of camosic acid when it is dissolved in methanol. The instability of camosic acid is probably due to air oxidation catalyzed by a transition metal ion such as iron, which often exists as impurity in polar solvents. It has been observed by Masuda et al. [25] that addition of a catalyst amount of ferric chloride to a solution of carbonic acid in acetonitrile leads the formation of products (92) and (93) in low yield. It has been found that the oxidation products do not show any activity. This observation confirms... 

Unfortunately, common mobile phases for RPLC utilize organic solvents, which may be detrimental to the ICPs analytical performance. A decrease in sensitivity can result due to excessive solvent loading of the plasma. Higher plasma instability, increased background at certain masses due to the formation of molecular ions and carbon deposition on the sampling cone of ICP have been reported. Use of mobile phases that do not utilize file conventional organic solvents is therefore worthwile. Micellar mobile phases have been proposed for RPLC/ICP-MS speciation... 

Sun ZF, Yu KT (2002) Absorption and desorption of carbon dioxide in and from organic solvent effects of Rayleigh and Marangoni instability. Ind Eng Chem Res 41 1905-1913... 

Nonaqueous electrolyte solutions can be reduced at negative electrodes, because of an extremely low electrode potential of lithium intercalated carbon material. The reduction products have been identified with various kinds of analytical methods. Table 3 shows several products that detected by in situ or ex situ spectroscopic analyses [16-29]. Most of products are organic compounds derived from solvents used for nonaqueous electrolytes. In some cases, LiF is observed as a reduction product. It is produced from a direct reduction of anions or chemical reactions of HF on anode materials. Here, HF is sometimes present as a contaminant in nonaqueous solutions containing nonmetal fluorides. Such HF would be produced due to instability of anions. A direct reduction of anions with anode materials is a possible scheme for formation of LiF, but anode materials are usually covered with a surface film that prevents a direct contact of anode materials with nonaqueous electrolytes. Therefore, LiF formation is due to chemical reactions with HF [19]. Where does HF come from Originally, there is no HF in nonaqueous electrolyte solutions. HF can be produced by decomposition of fluorides. For example, HF can be formed in nonaqueous electrolyte solutions by decomposition of PF6 ions through the reactions with H20 [19,30]. 

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