Tetraphenylphosphonium Tetraoxorhenate VII

TETRAPHENYLPHOSPHONIUM TETRAOXORHENATE(VII) Na[ReC 4] + [Ph4P]Br - [Ph4P] [Re04] + NaBr 

A warm (60°C) solution of sodium perrhenate (1.5 g, 5.5 mmol) in demineralized water (60 mL) in a 250-mL conical flask is added to a warm (60°C) solution of tetraphenylphosphonium bromide (2.8 g, 6.7 mmol) in demineralized water (60 mL) contained in a 250-mL conical flask. The mixture is then stirred for 30 min at room temperature. The white precipitate which forms is collected by filtration on a No. 3 sintered-glass filter tube, washed with distilled water (4 x 20 mL) and absolute ethanol (4 x 30 mL), and then dried in vacuo for 5 h at 56°C (boiling acetone) (yield 2.80 g, 87%). 

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