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Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Crystal structure of di-μ-iodido-bis{[bis(piperidin-1-yl)methane-κ(2) N,N']copper(I)}
Eva Rebecca Barth1, Christopher Golz1, Carsten Strohmann1
1Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany.
Abstract:
The title compound, [Cu2I2(C11H22N2)2], crystallizes as a symmetric dimer with one quarter of the mol-ecule in the asymmetric unit. The copper(I) atom, the iodine atom and the central methyl-ene C atom of the di(piperidin-1-yl)methane ligand lie on a mirror plane and the complete molecule exhibits point group symmetry 2/m. To the best of our knowledge it is the first di-amine copper(I) complex containing a four-membered chelate ring. Compared to other di-amine copper(I) iodide dimers, the title compound has a short Cu⋯Cu distance of 2.5137 (11) Å, but a long Cu-N bond length of 2.213 (3) Å. The I-Cu-I angle [121.84 (2)°] is large, and the N-Cu-N angle = 66.61 (13)° is the smallest one found for copper(I) di-amine complexes. As a result of the four-membered ring, the ligands around the copper(I) atom have an extremely distorted tetra-hedral arrangement. In the crystal, there are no significant inter-molecular inter-actions present.
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