Rhenium oxide with dioxane

Rhenium(VI) oxide can be prepared by the incomplete combustion of rhenium in oxygen, but the reaction is hard to control. It can also be obtained by the reduction of rhenium(VlI) oxide (1) with rhenium at elevated temperatures and (2) with rhenium(IV) oxide at 300°. These procedures are unsatisfactory, as difficulty is experienced in removing unreacted rhenium or rhenium (VII) oxide. Simpler procedures that lead directly to pure products involve reducing rhenium(VII) oxide with either dioxane or carbon monoxide. 

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