Recycling organoiridium waste to [(1,5-cyclooctadiene)IrCl]2

Abstract

We report the first process for iridium element recovery from organoiridium waste that is quantitative, pyrolysis-free, and generates no iridium metal. The key step is oxidative degradation of the waste by bleach to crude iridium(IV) hydroxide. Its treatment with hydrazine and then hydrogen peroxide gives synthetically important hexachloroiridic acid, which is converted to [(1,5-cyclooctadiene)IrCl]₂ in 87% yield.