The nacnac Cu(I) compound [L¹Cu(MeCN)] (L¹ = [{N(C₆H₃Me₂-2,6)C(Me)}₂CH]⁻) was reacted with E₄ (P₄, As₄ and AsP₃) yielding the homobimetallic complexes [(L¹Cu)₂(η^2:2-E₄)] (E₄ = P₄ (1a), As₄ (1b), AsP₃ (1c)) and the mononuclear complexes [L¹Cu(η²-E₄)] (E₄ = P₄ (2a), As₄ (2b), AsP₃ (2c)), revealing neutral, intact side-on coordinated E₄ units. Furthermore, the reaction of [L¹Cu(MeCN)] with Se_red and E₄S₃ (E = P, As) afforded [(LCu)₂(μ,η^2:2Se₂)] (L¹ = 3a, L³ = 3b) and [(L³Cu)₂(E₄S₃)] (E = P (4), As (5)). They represent rare examples of complexes of group 11 metals with polypnictogen, chalcogen and mixed E15/Q16 compounds.