Amines base metal salts

Later a breakthrough came when a series of weak base catalysts were discovered that are more active than sodium carbonate or tertiary amines. Alkali metals salts of phosphoric, polyphosphoric, phosphorous, and hypophosphorous adds were proven effective [376,385-389]. 

Lewis base salts (imidazole versus imidazolium salts or tertiary amine versus quaternary amine salts) do not change the mechanism. They follow the same order as Lewis bases. Metal salt complexes with tertiary amines may be more latent than tertiary amines, probably due to the absence of solvolysis of the... 

CHEMICAL PROPERTIES incompatible with amines, SO2, metal salts, thiourea, di-methylamine, bases, oxidizers, reducing agents, oxygen unstable HC (-6950 cal/g) AT (219°C) FP (-6°C) LFL/UFL (2.8%, 31%)... 

Catalysts used are both amines and metal salts, mainly tin based, and sometimes in coitiiinations. 

Aromatization of CHD-bismethylcarbonate derivatives are reported to be catalyzed by bases (metal salts, amines, amide solvents) resulting in sig-... 

Other commercially snccessful reactive acrylic-based adhesives are mixtures of methacrylate polymers dissolved in methyl methacrylate (MMA) monomers. Extensive research and development of these adhesives first introduced in the 1960s have led to what is termed high-performance acrylic adhesives. These products are supplied as two separate components to be mixed prior to an application. A peroxide in one component and an amine or metal salt (reducing agent) in the other initiate a free-radical polymerization of the MMA upon mixing [16]. 

Chemical Properties. A combination of excellent chemical and mechanical properties at elevated temperatures result in high performance service in the chemical processing industry. Teflon PEA resins have been exposed to a variety of organic and inorganic compounds commonly encountered in chemical service (26). They are not attacked by inorganic acids, bases, halogens, metal salt solutions, organic acids, and anhydrides. Aromatic and ahphatic hydrocarbons, alcohols, aldehydes, ketones, ethers, amines, esters, chlorinated compounds, and other polymer solvents have Httle effect. However, like other perfluorinated polymers,they react with alkah metals and elemental fluorine. 

Decomposition Hazards. The main causes of unintended decompositions of organic peroxides are heat energy from heating sources and mechanical shock, eg, impact or friction. In addition, certain contaminants, ie, metal salts, amines, acids, and bases, initiate or accelerate organic peroxide decompositions at temperatures at which the peroxide is normally stable. These reactions also Hberate heat, thus further accelerating the decomposition. Commercial products often contain diluents that desensitize neat peroxides to these hazards. Commercial organic peroxide decompositions are low order deflagrations rather than detonations (279). 

Salt Formation. Citric acid forms mono-, di-, and tribasic salts with many cations such as alkahes, ammonia, and amines. Salts may be prepared by direct neutralization of a solution of citric acid in water using the appropriate base, or by double decomposition using a citrate salt and a soluble metal salt. 

Metal salt Amine base Solvent TemprC Time/h Yield/% ee %... 

When a carbonyl group is bonded to a substituent group that can potentially depart as a Lewis base, addition of a nucleophile to the carbonyl carbon leads to elimination and the regeneration of a carbon-oxygen double bond. Esters undergo hydrolysis with alkali hydroxides to form alkali metal salts of carboxylic acids and alcohols. Amides undergo hydrolysis with mineral acids to form carboxylic acids and amine salts. Carbamates undergo alkaline hydrolysis to form amines, carbon dioxide, and alcohols. 

PVP, a water soluble amine-based pol5mer, was found to be an optimum protective agent because the reduction of noble metal salts by polyols in the presence of other surfactants often resulted in non-homogenous colloidal dispersions. PVP was the first material to be used for generating silver and silver-palladium stabilized particles by the polyol method [231-233]. By reducing the precur-sor/PVP ratio, it is even possible to reduce the size of the metal particles to few nanometers. These colloidal particles are isolable but surface contaminations are easily recognized because samples washed with the solvent and dried in the air are subsquently not any more pyrophoric [231,234 236]. 

Eyal, A. M. Kogan, L. Bressler, E. Extraction of metal salts by mixtures of water-immiscible amines and organic acids (acid-base couple extractants). 2. Theoretical treatment and analysis. Ind. Eng. Chem. Res. 1994, 33, 1076-1085. 

The reaction to form the palladium complex is similar to that reported for amine salts, although here, because a bidentate chelating ligand is used, no chlorine atoms are retained in the complex, and the system is easy to strip. Also, as both reactions involve initial ion pair extraction, fast kinetics are observed with 3-5 min contact time to reach equilibrium at ambient temperature. The extraction conditions can be easily adjusted in terms of acidity to suit any relative metal concentrations and, because the reagent is used in the protonated form, good selectivity over base metals, such as iron and copper,... 

Michael reactions are base catalyzed and reversible, and so it is common to use either the nitronate salt of the nitroalkane substrate or the nitroalkane in the presence of a catalytic amount of alkali metal hydroxide, alkoxide or amine base. 

This method involves formation of reverse micelles in the presence of surfactants at a water-oil interface. A clear homogeneous solution obtained by the addition of another amine or alcohol-based cosurfactant is termed a Microemulsion. To a reverse micelle solution containing a dissolved metal salt, a second reverse micelle solution containing a suitable reducing agent is added reducing the metal cations to metals. The synthesis of oxides from reverse micelles depends on the coprecipitation of one or more metal ions from... 

Mercaptoaldimes 258 and 259 form Schiff bases with amines which are of considerable interest as complexing agents, producing chelates 262 and 263 with metal salts. 

Solvent extraction of base metals by amine salts 802... 

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