Silver salt replacement series

Dichloro - tetrammino - platinic Bromide, [Pt(NH3)4Cl2]Br2, is produced by treating the nitrate of the series with ammonium bromide, when the salt is precipitated as a yellow crystalline powder. Silver nitrate replaces two atoms of bromine by two nitrate radicles. 

H. N. Stokes prepared diimidotriphosphoric add, PO(OH)2.NH.PO(OH). NH.PO(OH)2, by heating trimetaphosphimic acid for about seven minutes with nitric acid. The soln. was then treated with an excess of ammonia, and a magnesium salt, and filtered. The acid in question appeared in the filtrate. The silver salt was precipitated by the addition of silver nitrate. Diimidotriphosphoric acid forms two series of salts—an acid salt with three, and a normal salt with five atoms of hydrogen replaced by the metal. For example, trisodium diimidotriphosphate,... 

As a follow-up work, Yu et al. succeeded to develop O-methyl hydroxamic acids-directed P-C(sp )-H arylation with aryl boronic acids imder mild reaction conditions in 2008 (Scheme 1.6) [23]. Remarkably, they identified that air could be employed as a sustainable external oxidant to replace silver salts (Scheme 1.6b). Since the O-methyl hydroxamic acids are readily to undergo a series of organic transformations, this protocol provides a facile access to a class of bioactive target molecules. 

C. Kubierschky 6 prepared a series of oxythiophosphates with only part of the oxygen of the normal phosphates replaced by sulphur. He said that acids decompose all thiophosphates hydrogen sulphide is evolved, and, in some cases, sulphur separates. Monothiophosphates give white precipitates with calcium, barium, and strontium salts, the dithiophosphates with barium and strontium salts, and the trithiophosphates with barium salts only. All thiophosphates yield precipitates with cadmium, copper, silver, and mercurous salts, which decompose after a time,... 

One of the ions of a precipitate can be replaced by a foreign ion of the same charge, provided the ions do not differ in size by more than about 5% and provided the two salts crystallize in the same system. Thus silver chloride and silver bromide form a complete series of solid solutions by isomorphous replacement of bromide by chloride. 

If the thallium dipiieiiyl cliloride be replaced by thallium diethyl bromide, only thallous iodide is isolated from the reaction. It has been pointed out that thallium dialkyJ halides when treated with moist silver oxide yield the corresponding hydroxides, and that the latter with acids give salts. In the aromatic series, it is found that the best method of preparing the salts is to boil together a mixture of the halide, silver oxide, and the organic acid in toluene. Alcoholic potassium hydroxide transforms the halides to oxides, and these are also available for production of salts. 

With bases, this acid forms one series of salts, the monobasic phosphates, the general formula of which is P, 0, MO, or P, Oj, M. In these, the hydrogen of the acid is replaced by its equivalent of metal. The precipitate caused by the acid in solutions of silver is one of these salts, P, O5, Ag 0. 

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