Hydroxy basic salts

The term basic salt is applied to a variety of compounds intermediate between the normal salt and the hydroxide or oxide. This broad definition includes compounds such as Be and Zn oxyacetates (p. 416), oxy- and hydroxy-halides (Chapter 10), 

Basic salts may be prepared in various ways, which usually involve—directly or indirectly-hydrolysis of a normal salt. The hydrolysis may be carried out under conditions of controlled temperature, acidity, and metal-ion concentration, or indirectly by heating a hydrated salt. Many hydroxy-salts are formed by the latter process instead of the anhydrous normal salts, for example, Cu2(0H)3N03 by heating hydrated cupric nitrate. The precipitates formed when sodium carbonate solution is added to metallic salt solutions are often hydroxy-carbonates. Some metals do not form normal carbonates (e.g. Cu, see p. 887) others such as Pb, Zn, Co, and Mg form normal or hydroxy-salts according to the conditions of precipitation. Lead, for example, forms 2 PbC03. Pb(OH)2 and PbC03. Pb(OH)2, both of which occur as minerals, while Co forms Co4(OH)6C03 in addition to the normal carbonate. 

Before describing the structures of a few hydroxy-salts we should mention that structural formulae have been assigned to some of these compounds on the supposition that they are Werner coordination compounds. We may instance  

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E. Divers prepared the basic salt cupric hydroxy hyponitrite, Cu2(0H)2N202, according to A. Thum. This salt was also made by S. S. Kolotoff, A. Thum, and A. Kirsehner. It is obtained by adding sodium hyponitrite to a soln. of a cupric salt. The acid liquor so obtained deposits more salt when neutralized. A small quantity of this salt is precipitated when an excess of cupric sulphate is added to a soln. of hydroxylamine sulphate, and then a little ammonia. The sea-green salt is very stable it gives water, a mixture of cupric and cuprous oxides, and nitric and nitrous oxides when heated. The salt can be boiled with water without losing its colour, but it is decomposed by a soln. of sodium hydroxide. It is soluble in dil, acids and aq. ammonia. E, Divers tried unsuccessfully to make cuprous... 

With perchlorate ions, which interact less strongly with precipitating copper(II) ions, nucleation of precipitated copper species proceeds at a significantly higher pH level, as can be concluded from Fig. 16. When more alkali has been added, reaction of the basic salt initially precipitated to (brown or black) copper oxide, which is more stable, takes place. Consequently, a drop in pH level is exhibited due to the exchange of perchlorate ions for hydroxy ions. With suspended silica the pH curve runs initially below the level measured without suspended silica. The stabilization of the copper species precipitated by interaction with the support is evident from the fact that now no copper oxide results when more alkali has been added. The loaded support displays still a blue color when the precipitation has finished which is maintained after drying at 383 K. 

Lonthonum Triazide, La(N5), mw 222.97, N37.25JJ, Curtius and Darapsky prepd the basic salt. Lanthanum Hydroxy azide. La (OH)(Nj), l/ H,0, by boiling a soln of lanthanum nitrate and sodium azide. The white slimy mass of basic lanthanum azide was obtained either on evapg the mixed soln in vacuo or on treating it with a mixt of ale eth. No props of the product were reported nor were there any addnl refs found in which any attempts were made to prepare and isolate the lanthanum azide... 

In accord with the relatively high basicity of cyclopropenone (pXb = - 5.2 0.3) and its derivatives (substituents at C(l) and C(2) increase the basicity alkyl more so than phenyl), these compounds are protonated in strong acids to give the corresponding hydroxy-cyclopropenium salts e.g. 321 (R = The salts generated in this manner can... 

Basic bismuth salicylate Bismogenol tosse inj Bismuth, (2-hydroxybenzoato-01,02)oxo- Bismuth oxide salicylate Bismuth, oxo(salicylato)- Bismuth oxy-salicylate Bismuth salicylate, basic Bismuth subsalicylate CCRIS 4761 EINECS 238-953-1 HSDB 332 (2-Hydroxybenzoato-0 )-oxobismuth 2-Hydroxy-benzoic acid bismuth(3- ) salt 2-Hydroxybenzoic acid bismuth (3- ) salt, basic Salicylic acid basic bismuth salt Salicylic acid, bismuth basic salt ... 

Propanetricarboxylic acid, 2-hydroxy-, triammonium salt. See Ammonium citrate tri basic... 

The formation of basic salts results from the reaction of zinc hydroxide with certain constituents of the atmosphere. For example, the reaction of zinc hydroxide with carbon dioxide leads to formation of weakly soluble hydroxy-carbonates (or basic carbonates) with the general formula Zn(0H)x(C03)y ... 

Green patina, whose decorative aspect is highly appreciated, contains mostly basic salts. Their exact composition depends on the atmospheric conditions. In urban atmospheres they are mostly composed of hydroxy-sulfates and in marine atmospheres of hydroxy-chlorides. The patina forms more rapidly in polluted atmospheres, but even so, one generally has to wait a few years for a green patina to appear. Environments with a high SO2 concentration can prevent entirely the formation of the green patina, because the surface pH of the metal remains too low for the precipitation of basic salts. 

The reaction of a poly hydroxy base with less than a stoichiometric amount of an acid forms a basic salt, that is, a salt that contains unreacted OH groups. For example, the reaction of aluminum hydroxide with hydrochloric add can produce two different basic salts ... 

LDHs are the most investigated anion-exchangeable layered materials, but other examples of crystals belonging to this family are layered hydroxide (or basic) salts and layered hydroxy double salts. Layered phosphate and phosp-honate ° can also be nsed for the preparation of layered organo-modified derivatives through topotactic exchange reactions with anionic moieties. 

Hydrogen Sulfide andMercaptans. Hydrogen sulfide and propylene oxide react to produce l-mercapto-2-propanol and bis(2-hydroxypropyl) sulfide (69,70). Reaction of the epoxide with mercaptans yields 1-aLkylthio- or l-arylthio-2-propanol when basic catalysis is used (71). Acid catalysts produce a mixture of primary and secondary hydroxy products, but ia low yield (72). Suitable catalysts iaclude sodium hydroxide, sodium salts of the mercaptan, tetraaLkylammonium hydroxide, acidic 2eohtes, and sodium salts of an alkoxylated alcohol or mercaptan (26,69,70,73,74). 

Zinc forms salts with acids but since it is amphoteric, it also forms zincates, eg, [Zn(OH)2 H20] and Z.n([7) ). The tendency of zinc to form stable hydroxy complexes is also important because some basic zinc salts are only slightly soluble in water. Examples are 3Zn(OH)2 ZnSO [12027-98-4] and 4Zn(OH)2 ZnCl2 [11073-22-6] which may precipitate upon neutralization of acidic solutions of the salts. 

Further substitution of benzoic acid leads to a drug with antiemetic activity. Alkylation of the sodium salt of p-hydroxy-benzaldehyde (8) with 2-dimethylaminoethyl chloride affords the so-called basic ether (9). Reductive amination of the aldehyde in the presence of ammonia gives diamine, 10. Acylation of that product with 3,4,5-trimethoxybenzoyl chloride affords trimetho-benzamide (11). ... 

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