The multiplication in a quasiassociative algebra R satisfies the property a ∗ (b ∗ c)− (a ∗ b) ∗ c = b ∗ (a ∗ c)− (b ∗ a) ∗ c, a, b, c ∈ R. (∗∗) This property is necessary and sufficient for the Lie algebra Lie(R) to have a phase space. The above formulae are put into a cohomological framework, with the relevant complex being different from the Hochschild one even when the relevant quasiassocia...