Reaction with metal salts

Since Steiner s aim was to improve immaterial qualities of foods, anthroposophic scientists have developed analytical methods, which aim to visualize this kind of inner quality. This is done by preparing watery solutions of the plant, meat or milk (= juices) which are then brought into reaction with metallic salts like copper chloride (copper chloride crystallization method)... 

Aqueous solutions of ammonium nitrate undergo a double decomposition reaction with metal salts. NH4NO3 acts as an oxidizing agent in aqueous solutions and is reduced by various metals at ambient temperatures. 

Reactions with Metal Salts. Interactions of asphaltenes with the metal chlorides yield products containing organically bound chlorine, but the analytical data indicate dehydrogenation processes occurring simultaneously (12). There is, of course, no clear way by which the extent of the dehydrogenation can be estimated, but it may be a dehydro-... 

Zinc selenide (lrtran-4) 20,000-650 2.4 Brittle releases H2Se, a toxic material, if used with acids water insoluble electrochemical reactions with metal salts or complexes are possible... 

Reactions with Metal Salts or Metal Complexes.227... 

I.2.I.4. Addition Reactions with Metal Salts Yielding Stable Organometallics... 

Poly(2-alkyl oxazoline)s having methacrylate or acrylate end groups were prepared by two methods [182]. a) Living polyoxazoline chains, prepared using methyl p-toluene sulphonate as initiator, were end-capped by reaction with metal salts or tetraalkylammonium salts of acrylic or methacrylic acid or a trialky-lammonium salt or trimethylsilyl ester of methacrylic acid (functional termination). b) The living polymers were terminated with water in the presence of Na2C03 to provide hydroxyl-terminated chains. Subsequent acylation with acry-loyl or methacryloyl chloride in the presence of triethylamine led to the formation of the macromonomers. The procedures are outlined in the following Scheme 51. 

The cyclopropanation reaction with metal salts is readily amenable to asymmetric induction in the presence of a chiral ligand, and some excellent enantioselectivi-ties have been achieved. Particularly effective are the bisoxazoline ligands, developed by Pfaltz, Masamune and Evans. Both enantiomers of the chiral ligand are available and the reaction is amenable to a wide variety of different alkenes. For example, very high selectivity in favour of the cyclopropane 118 was achieved using only small amounts of the bisoxazoline ligand 117 and copper triflate (4.94). 

Another method of preparation involves the reaction with metal halides in the presence of a reducing agent (8.177). The nickel compound may also be prepared by ligand exchange as in (8.178) where the whole ligand is replaced. In certain cases direct reaction with metal salts can occur (8.179-8.181). 

Reaction with Metallic Salts. Ammonia solutions will react with some metallic salts to form complexes. 

The preparation of metal chelate polymers from bis(o-hydroxyazo) ligands has been reported. Bis[(o-hydroxyphenyl)azo]- [49] (18-20) and bis(3-hydroxy-4-azopyrazolone) [50] (19,20) compounds are polymerizable. With both classes of ligands, black, intractable products were obtained on reaction with metal salts. Only Cu(II) polymers have been investigated. Dimethylformamide, dioxane, and dioxane-ethanol mixtures were used as solvents. The products were not characterized because of their insolubility. 

Aliphatic 42) and aromatic 131, 132) tetracarboxylic acids have been polymerized with tetravalent metal and metalloidal salts. Low molecular weight prod ucts that decomposed at less than 200°C were obtained by reaction of silicon tetrachloride with aliphatic tetraacids. Pyromellitic acid and 2,3,6,7-naphthalenetetracarboxylic acid are converted to polymers by reaction with metal salts in water at 100°C (IX-32). The thermal stabilities of thorium-containing products were compared. The naphthalene-derived polymer was found to be less stable (360°C d) than the pyromellitic polymer. This result was attributed to the possibility that in thorium pyromellitate the thorium coordination shell is completed exclusively by carbonyl groups of neighboring chains, whereas in the naphthalene salt, water occupies two of the coordination sites of thorium. Uranium salts were less stable thermally than the thorium analogs 131). 

Method 1. Polymerization of Mercaptans with Metal Salts The earliest suggestion that monomercaptans yield polymers from reaction with metal salts was made by Mann and Purdie in 1935. The mercaptan was added to a chloroform solution of ammonium chloropalladite (IS). Red-orange solids were obtained from aliphatic mercaptans. The polymeric structure was proposed because the products did not conduct electricity. 

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