Silver salts reactions with

Another way of replacing chloride trans to phosphine involves using silver salts reaction with AgPF6 and AgN03 introduces, respectively, a water molecule (XII) and a nitrate group (IX), which may in turn be replaced by a range of Lewis bases, giving (VIII), (X) and (XXV). 

Silver nitrate test The compound to be tested is treated with a few drops of 1% alcoholic silver nitrate. A white precipitate indicates a positive reaction. This could be due to either silver chloride (reaction with a reactive alkyl halide), silver alkynide (reaction with a terminal alkyne), or the silver salt of a carboxylic acid (reaction with a carboxylic acid). 

The hydroxy-binaphthyl functionalised saturated imidazolium salt is readily available from 1-amino-I -hydroxy-binaphthyl in a reaction with a ( oc-protected mesitylamine aldehyde [86] (see Figure 4.24). The resulting Schiff base is reduced to the diamine by Na(OAc)3BH. Subsequent deprotection and ring closure reaction with triethyl orthoformate yields the corresponding hydroxy-binaphthyl functionalised saturated imidazolium salt. Reaction with silver(I) carbonate and subsequent carbene transfer to the ruthenium(II) precursor yields the asymmetric olefin metathesis precatalyst. 

Ab initio calculations indicated that the cyclopropiminium ion is more stable than the 2-aminoallyl cation.As allyl cations can be generated from the reaction of allylic halides with silver salts, ° reactions of a-haloenamines with these salts have been investigated in order to increase the yield and chemoselectivity of the formation of bicyclo[3.1.0]hexan-6-one aminals. ° ... 

Silver fluoborate, reaction with ethyl bromide in ether, 46, 114 Silver nitrate, complexing with phenyl-acetylene, 46, 40 Silver oxide, 46, 83 Silver thiocyanate, 46, 71 Sodium azide, reaction with f-butyl chloroacetate, 46, 47 reaction with diazonium salt from fi-amino-/> -nitrobiphenyl, 46,... 

The intracellular osmiophilic area of the flavonoid gland can be correlated to flavonoids because of their heavy staining after osmium tetroxide fixation. However, at some stages of the synthetic process, flavonoids are not osmiophilic. Hence, other electron microscopic techniques for polyphenol detection are also used. Ultra-chemical tests with silver salt reactions are the most interesting ones (Eef. 13) Such investigations have been successfully applied, but in many oases are limited by... 

Mercuric and mercurous salts may be detected by the formation of a brown or yellow precipitate with chromotropic acid. The test is carried out on filter paper [Idn. Limit 100 y Hg). Acids and silver salts interfere with this reaction. 

In the former, it gives precipitates with halides (except the fluoride), cyanides, thiocyanates, chromates(VI), phosphate(V), and most ions of organic acids. The silver salts of organic acids are obtained as white precipitates on adding silver nitrate to a neutral solution of the acid. These silver salts on ignition leave silver. When this reaction is carried out quantitatively, it provides a means of determining the basicity of the acid... 

Reaction with alcoholic silver nitrate. To carry out the test, treat 2 ml. of a 2 per cent, solution of silver nitrate in alcohol with 1 or 2 drops (or 0 05 g.) of the compound. If no appreciable precipitate appears at the laboratory temperature, heat on a boiling water bath for several minutes. Some organic acids give insoluble silver salts, hence it is advisable to add 1 drop of dilute (5 per cent.) nitric acid at the conclusion of the test most silver salts of organic acids are soluble in nitric acid. 

Alkyl esters of trifluoromethanesulfonic acid, commonly called triflates, have been prepared from the silver salt and an alkyl iodide, or by reaction of the anhydride with an alcohol (18,20,21). Triflates of the 1,1-dihydroperfluoroalkanols, CF2S020CH2R can be prepared by the reaction of perfluoromethanesulfonyl fluoride with the dihydroalcohol in the presence of triethylamine (22,23). Triflates are important intermediates in synthetic chemistry. They are among the best leaving groups known, so they are commonly employed in anionic displacement reactions. 

Dicyano-l,2,3-trithiole 2-oxide (143) has been prepared from the silver salt of 2,3-dimercaptomaleonitrile (142) and thionyl chloride (66HC(2l-i)67). Similarly, the reaction of ethylene glycol (144) with thionyl chloride gave 1,3,2-dioxathiolane 2-oxide (145), the parent compound of saturated five-membered cyclic sulfites (see Chapter 4.33). 

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