Phosphoryl bromide chloride

Lithium chloride Phosphorus oxybromide and oxychloride (phosphoryl bromide and chloride)... 

Arsenic triiodide also dissolves, the saturated solution at 15° C. having density 3-661. Other soluble halides are potassium bromide, anhydrous ferric and aluminium chlorides 6 and tetramethyl ammonium iodide but the iodides of rubidium, cadmium, manganese and cobalt, also mercuric and stannic iodides, and cobalt and stannic bromides, are insoluble or only very slightly soluble in arsenic tribromide. The liquid also dissolves phosphoryl bromide and, very slightly, ammonium thiocyanate. In the mixed solutions of halides, the components may react chemically (cf. p. 106), but such is not always the case for example, with antimony tribromide a continuous series of solid solutions is formed.7... 

He found that with ordinary commercial red phosphorus with 98 per cent, phosphorus, there dissolved 0-056 and 0-108 per cent, of phosphorus in respectively 10 and 42 hrs., and with a finely-divided sample 0-092 and 0-116 percent, phosphorus in 10 and 20 hrs. respectively. R. Schenck found that 100 grms. of phosphorus tribromide dissolved 0-2601 grm. of scarlet phosphorus at 172°, and 0-3634 grm. at 184°. E. Baudrimont showed that yellow phosphorus does not attack phosphoryl bromide at the b.p. L. Rosenstein found that soln. of arsenates, and arsenic, antimony, or bismuth salts are not reduced by boiling with red phosphorus but W. Finkelstein found that a nitrobenzene soln. of arsenic trichloride is reduced by yellow phosphorus and arsenic is deposited. 0. Ruff observed that phosphorus reacts with antimony trichloride in the presence of a little aluminium chloride. F. E. Brown and J. E. Snyder observed that vanadium oxytrichloride is without action on red or white phosphorus. 

The conversion of a tautomeric 1,5-naphthyridinone into the corresponding chloro- or bromo-l,5-naphthyridine is usually done by heating for several hours with neat phosphoryl chloride or phosphoryl bromide, respectively. A mixture of phosphoryl chloride and phosphorus pentachloride has been used for a few difficult cases. In addition, exceptional reactions have been reported in which a nontautomeric /V-alkyl-1,5-naphthyridinone or a hydroxymethyl-1,5-naphthyridine was used successfully as substrate. The following examples illustrate the foregoing possibilities. 

Note The chlorolysis of naphthyridinones or naphthyridinoles is usually done with neat phosphoryl chloride to which may be added phosphorus pentachlor-ide or dimethylformamide in difficult cases corresponding bromolysis is achieved by the use of phosphoryl bromide and the chlorolysis of (extra-nuclear) hydroxyalkyl-1,8-naphthyridines may be done with thionyl chloride with or without added zinc chloride. Typical examples of these procedures are given here. 

Note At least in simple cases, the Meissenheimer reaction appears to be unsatisfactory for the production of halogeno-l,8-haphthyridines. Thus 1,8-naphthyridine 1-oxide with phosphoryl chloride gave a difficult-to-separate mixture of 2-, 3-, and 4-chloro-l,8-naphthyridine (in ratio 36 7 57) 225 phosphoryl bromide and bromine/acetic acid both gave even worse mixtures... 

The classical route to chloropyrazines is by treatment of a hydroxy-pyrazine with phosphoryl chloride bromopyrazines are similarly prepared by using phosphoryl bromide, phosphorus tribromide, or a mixture of both. Thus, treatment of hydro xypyrazine with phosphoryl chloride gives chloropyrazine in 92% yield,147 and treatment of the hydroxy compound with a mixture of phosphoryl bromide and phosphorus tribromide gives bromopyrazine in 58% yield.266 The use of phosphorus pentahalides frequently leads to substitution products (Scheme 22) for example, when hydroxypyrazine is treated with a mixture of phosphoryl bromide and phosphorus pentabromide both monobromo- and 2,6-dibromopyrazines are formed.287,268 Bromina-tion of hydroxypyrazine with bromine in the presence of small... 

Reactions with thionyl chloride and acetyl chloride have been described (838). f This reaction with phosphoryl bromide. 

JV-nitrosodimethylamine and phosphoryl chloride (Scheme 37). The formation of isoalloxazines by the action of phosphoryl bromide and DMF on... 

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