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Despite being weak attractive forces, closed‐shell metallophilic interactions play important roles in the Group 11 metal complexes on their diverse structural and physical features. A plethora of experimental and computational studies has thus been dedicated to such weak attractive d10–d10 interactions, particularly aurophilic and argentophilic interactions. Although d10–d10 CuI–CuI forces had been recognized for four decades, cuprophilic interactions are less explored and they are best evidenced by single‐crystal X‐ray crystallographic analysis on CuI complexes and aggregates thereof, by which precise information about the Cu⋅⋅⋅Cu contacts, shorter than the sum of two van der Waals radii (3.92 Å) between the copper centers concerned can be obtained. Based on recently compelling experimental and spectroscopic evidence for intra‐ and intermolecular cuprophilic interactions in copper chemistry, the present Minireview summarizes recent progress in the past three decades in the synthesis and structures of multinuclear homometallic copper complexes, whereby supported and unsupported d10–d10 CuI–CuI interactions are at work.

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Treatment of [Cr(μ-Cl)(Nacnac)]2 (Nacnac = HC(C(Me)NC6H3-i-Pr2)2) with 2.5 equiv of KC8 in toluene allows the isolation of an inverted-sandwich toluene-bridged complex, (μ-η6:η6-C7H8)[Cr(Nacnac)]2 (1), in 88.2% yield as a dark-purple solid. The valency of each Cr is determined to be I by X-ray absorption spectroscopy. The twelve Cr−C distances are moderately long and 1 readily undergoes an arene exchange reaction with benzene. As a result, 1 behaves as a two-Cr(Nacnac) synthetic equivalents upon reaction with appropriate substrates. For example, treatment of 1 with 2 equiv of O2, 4 equiv of MesN3 (Mes = 2,4,6-C6H2Me3), and Ph2N2 engenders the formation of a monomeric Cr(O)2(Nacnac) (2), Cr(NMes)2(Nacnac) (3), and (μ-NPh)(Nacnac)]2 (4), respectively. Complex 1 is therefore an 8-electron reductant.