Halogen compounds, reaction with alcoholic silver nitrate

Halogen carriers, 533 Halogen compounds, reaction with alcoholic silver nitrate, 1059 reaction with sodium iodide in acetone, 1059, 1060 ... 

We have seen (Sec. 14.24) that an alkyl halide is conveniently detected by the precipitation of insoluble silver halide when it is warmed with alcoholic silver nitrate. The reaction occurs nearly instantaneously with tertiary, allyl, and benzyl bromides, and within five minutes or so with primary and secondary bromides. Compounds containing halogen joined directly to an aromatic ring or to a doubly-bonded carbon, however, do not yield silver halide under these conditions. Bromo-benzene or vinyl bromide can be heated with alcoholic AgN03 for days without the slightest trace of AgBr being detected. In a similar way, attempts to convert aryl... 

If a compound is known to contain bromine, chlorine, or iodine, information concerning the environment of the halogen is obtained from reacting the substance with alcoholic silver nitrate. The overall reaction is shown in Equation 25.29. 

P-DIMETHYLAMINOETHYL ALCOHOL (108-01-0) Forms explosive mixture with air (flash point 105°F/41°C oc). An organic base. Violent reaction with oxidizers, acids. Ignites spontaneously with cellulose nitrate, and possibly with other nitrogen compounds. Silver, cobalt, or chromium compounds may cause explosions. Contact with nitromethane forms a heat-, friction-, and shock-sensitive explosive. Incompatible with acrylates, aldehydes, alcohols, alkylene oxides, caprolactam solution, cresols, organic anhydrides, substituted allyls, epichlorohydrin, glycols, halogenated compounds, isocyanates, ketones, mercury, phenols, vinyl acetate. Attacks copper, zinc, and their alloys, and galvanized steel. 

The reactivity of the normal alkyl halides varies with the halogen and with the alkyl group the more reactive are those with the smaller number of carbon atoms. The iodides are the most reactive, the chlorides the most inert. Methyl iodide is much used in organic syntheses, as it reacts readily with many substances and serves as a means of introducing the methyl group into such compounds. An alcoholic solution of methyl iodide reacts with a similar solution of silver nitrate in the cold, and silver iodide is formed. With ethyl iodide the reaction proceeds much more slowly, and with the higher alkyl iodides the application of heat is necessary to bring about reaction. 

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