Barium iodide, reaction

The natural history of chemistry consists since many centuries in empirical rules about the relative affinity of various elements. Though metathetical reactions are frequently used in preparation, the main origin is the filtering of insoluble precipitates, as when an aqueous solution of silver sulphate and another of barium iodide leave almost pure water in the filtrate ... 

Dibenzylphosphoric acid and dicyclohexylcarbodi-imide were used to generate tetrabenzyl phosphate. This could then be reacted with 2,3-isopropylidene-glycerol in the presence of imidazole to yield 2,3-iso-propylidene-5n-glycerol-l-dibenzyl phosphate. De-benzylation of the latter was carried out with barium iodide and the barium salt was converted to the silver salt which was reacted with 3-iododeoxy-l-oleoyl-2-palmitoyl-5n-glycerol. The fully protected phosphatidylglycerol was debenzylated, followed by reaction with boric acid in trimethyl borate which effected removal of the isopropylidene group (Rosenthal, 1975). Yields of 30% are obtained (Slotboom and Bonsen, 1970). 

Borgford, and J. B. Ealy, "Name That Precipitate," Chemical Demonstrations, A Sourcebook for Teachers, Vol. 2 (American Chemical Society, Washington, DC, 1988), pp. 121-123. Blue, brown, red, white, and yellow precipitates are formed when solutions containing +2 cations of mercury, nickel, lead, and barium are mixed with solutions containing carbonate, chloride, iodide, and sulfate anions. Students are asked to name and determine the formula of each precipitate and to write an ionic equation for each reaction. 

These are usually reactions of anhydrous transition and B metal halides with dry alkali metal salts such as the sulphides, nitrides, phosphides, arsenides etc. to give exchange of anions. They tend to be very exothermic with higher valence halides and are frequently initiated by mild warming or grinding. Metathesis is described as a controlled explosion. Mixtures considered in the specific reference above include lithium nitride with tantalum pentachloride, titanium tetrachloride and vanadium tetrachloride, also barium nitride with manganese II iodide, the last reaction photographically illustrated. 

Phenylethylamine has been made by a number of reactions, many of which are unsuitable for preparative purposes. Only the most important methods, from a preparative point of view, are given here. The present method is adapted from that of Adkins,1 which in turn was based upon those of Mignonac,2 von Braun and coworkers,3 and Mailhe.4 Benzyl cyanide has been converted to the amine by catalytic reduction with palladium on charcoal,5 with palladium on barium sulfate,6 and with Adams catalyst 7 by chemical reduction with sodium and alcohol,8 and with zinc dust and mineral acids.9 Hydrocinnamic acid has been converted to the azide and thence by the Curtius rearrangement to /3-phenyl-ethylamine 10 also the Hofmann degradation of hydrocinnamide has been used successfully.11 /3-Nitrostyrene,12 phenylthioaceta-mide,13 and the benzoyl derivative of mandelonitrile 14 all yield /3-phenylethylamine upon reduction. The amine has also been prepared by cleavage of N- (/3-phenylethyl) -phthalimide 15 with hydrazine by the Delepine synthesis from /3-phenylethyl iodide and hexamethylenetetramine 16 by the hydrolysis of the corre-... 

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