Tetrakis(acetonitrile)copper(I) hexafluorophosphate is a salt with the formula [Cu(CH3CN)4]PF6.

[1] As confirmed by X-ray crystallographic studies, the copper(I) ion is coordinated to four almost linear acetonitrile ligands in a nearly ideal tetrahedral geometry.

[4] [Cu(CH3CN)4]PF6 is generally produced by the addition of HPF6 to a suspension of copper(I) oxide in acetonitrile:[5] The reaction is highly exothermic, and may bring the solution to a boil.

Upon crystallization, the resulting microcrystals should be white, though a blue tinge is common, indicating the presence of Cu2+ impurities.

[5] Water-immiscible organic nitriles have been shown to selectively extract Cu(I) from aqueous chloride solutions.