Phosphaniminato‐Acetato‐Cluster von Kupfer und Zink. Kristallstrukturen von [Cu4(NPEt3)2(O2CCH3)6] und [Zn4(NPEt3)2(O2CCH3)6]

Phosphoraneiminato Acetate Cluster of Copper and Zinc. Crystal Structures of [Cu₄(NPEt₃)₂(O₂CCH₃)₆] and [Zn₄(NPEt₃)₂(O₂CCH₃)₆] The anhydrous acetates of copper(II) and zinc react with the silylated phosphaneimine Me₃SiNPEt₃ in dichloromethane at 20 °C forming the mixed phosphoraneiminato acetate clusters [Cu₄(NPEt₃)₂(O₂CCH₃)₆] ( 1 ), which forms emerald crystals, and colourless [Zn₄(NPEt₃)₂ · (O₂CCH₃)₆] ( 2 ). In spite of analogous composition the structures of 1 and 2 are completely different. In the asymmetric unit of 1 three copper atoms of an almost isosceles triangle are linked via two nitrogen atoms of the NPEt₃^– groups to form a trigonal bipyramidal aggregate. One of these three copper atoms is chelated by an acetate group, another one is connected with the fourth copper atom via three μ₂‐O₂C–CH₃ groups. The asymmetric units are associated via a μ₂‐O₂C–CH₃ group and a μ₃‐OC(O)CH₃ group at a time so that infinite chains result. In 2 two zinc atoms are linked via the nitrogen atoms of the two NPEt₃^– groups to form an almost centrosymmetric four‐membered ring. Both nitrogen atoms of the four‐membered ring are connected with another zinc atom each. These zinc atoms again are linked with the zinc atoms of the Zn₂N₂ four‐membered ring via two μ₂‐O₂C–CH₃ groups each and additionally coordinated with a terminal acetate ligand each.