Linking Bridged Tetracopper Complexes with Neutral Dipyridyl Compounds to Coordination Polymers and Discrete Metalacages

Abstract

The bridged tetracopper(I) complex [{Cu2(μ‐dppm)2}2(μ‐(1,3‐O2CC6H4 (CO2 )2)](BF4 )2 (2(BF4 )2) was prepared. This complex and the neutral dipyridyl compounds (NN; NN = 4,4′‐bipyridine (bpy), 1,2‐bis(4‐pyridyl)ethane (bpa), 4,4′‐trimethylenedipyridine (tmp)) can form dynamic equilibria in CH2Cl2 . From the equilibrium mixtures containing 2(BF4 )2 and NN with 2(BF4 )2/NN = 1:1, different supramolecular compounds were obtained as single crystals, and their structure were determined by X‐ray crystallography. The flexibility of NN is found to be important in determining the outcome of the reactions with a rigid bpy, leading to the formation of the coordination polymer [{Cu2(μ‐dppm)2}2(μ‐1,3‐C6H4 (CO2 )2)(μ‐bpy)] n (BF4 )2n (3(BF4 )2n ), whereas with flexible bpa and tmp direct the formation of the metalacages [{Cu2(μ‐dppm)2}2(μ‐1,3‐C6H4 (CO2 )2)(μ‐NN)](BF4 )2 (NN = bpa, 4(BF4 )2; tmp, 5(BF4 )2), respectively, as supported by density functional theory (DFT) calculation results.