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Updated: Apr 17, 2026

Author Spotlight: Experimental Approaches for the Synthesis of Low-Valent Metal-Organic Frameworks from Multitopic Phosphine Linkers
Published on: May 12, 2023
Why are the {Cu4N4} rings in copper(I) phosphinimide clusters [Cu{μ-N = PR3}]4 (R = NMe3 or Ph) planar?
Thomas P Robinson1, Richard D Price, Matthew G Davidson
1Department of Chemistry, University of Bath, Bath, BA2 7AY, UK. M.G.Davidson@bath.ac.uk A.L.Johnson@bath.ac.uk.
Abstract:
The copper phosphinimide complexes [Cu{μ-N[double bond, length as m-dash]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 molecular structures of 1 and 2 reveal the presence of 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.
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