Pyrophosphoryl bromide

A. Michaelis did not succeed in making pyrophosphoryl bromide, P203Br4, by the action of nitrogen peroxide or trioxide on phosphorus tribromide—the products are phosphorus pentoxide and phosphoryl bromide. T. E. Thorpe and A. E. H. Tutton said metaphosphoryl bromide, P02Br, is produced by the action of bromine on phosphorous oxide as indicated above, and it remains as a residue after the phosphoryl bromide has been removed by distillation. 

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