Copper(II) acetylacetonate is the coordination compound with the formula Cu(O2C5H7)2.

It is insoluble within water and exists as a bright blue solid.

According to X-ray crystallography, the Cu center is square planar.

[1] Single crystals of this compound exhibit the unusual property of being highly flexible, allowing the formation of knots.

The flexibility is attributed to the nature of the intermolecular forces.