Most of the compounds have physiologically active properties, and their biological properties are often attributed to the heteroatoms contained in their molecules, and most of these heteroatoms also appear in cyclic structures. A Journal, Article, Dalton Transactions called Why are the {Cu4N4} rings in copper(I) phosphinimide clusters [Cu{μ-N:PR3}]4 (R = NMe3 or Ph) planar?, Author is Robinson, Thomas P.; Price, Richard D.; Davidson, Matthew G.; Fox, Mark A.; Johnson, Andrew L., which mentions a compound: 75732-01-3, SMILESS is [Cu]C1=C(C)C=C(C)C=C1C, Molecular C9H11Cu, Safety of Mesitylcopper(I).
The Cu phosphinimide complexes [Cu{μ-N:PR3}]4 (1, R = NMe2 and 2, R = Ph) were obtained in good yields from the reactions of Cu[Mes] (Mes = mesityl, C6H2Me3-2,4,6) with the corresponding iminophosphoranes, HNPR3. The mol. structures of 1 and 2 reveal planar eight-membered {Cu4N4} rings which contrasts with the saddle-shaped {M4N4} rings found in related metal phosphinimide complexes. According to computations, there is negligible aromaticity in the planar {Cu4N4} rings in 1 and 2 and the saddle shape observed in related {M4N4} rings is due to steric factors.
Here is just a brief introduction to this compound(75732-01-3)Safety of Mesitylcopper(I), more information about the compound(Mesitylcopper(I)) is in the article, you can click the link below.
Reference:
Iodide – Wikipedia,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com