Synthesis and structural characterization of Zintl anions containing the tris(ethylenediamine)-zinc cation: [Zn(N2C2H8)(3)][Te-3]center dot(0.5en) and [Zn(N2C2H8)(3)](2)[Sn2Te6]center dot(en)

Two Zintl anions which contain the [tris(ethylenediamine)-zinc](2+) cation have been synthesized and structurally characterized by single-crystal X-ray diffraction. When a constant current of 1 mA is applied between a ZnTe10 alloy cathode and a Ni plate anode, in a saturated solution of tetrapropylammonium bromide in ethylenediamine, a deep red-purple solution is generated around the cathode as polyanions are generated. After a few days, small, black crystals formed, which were identified by single crystal X-ray diffraction as [Zn(N2C2H8)(3)][Te-3]. 0.5(N2C2H8) (1). The 1:1:1 stoichiometric reaction of the Zintl phase K4SnTe4 with ZnCl2 in the presence of (C2H5)(4)NBr in ethylenediamine at 100 degrees C for 1 day in a sealed evacuated quartz tube gave crystals of [Zn(N2C2H8)(3)](2)[Sn2Te6].(en) (2). The structures of 1 and 2 consist of discrete anions which are surrounded in the solid state by the tris(ethylenediamine)-zinc cations. Copyright (C) 1997 Elsevier Science Ltd.