Cyclische Diazastannylene, III1 Die Kristall-und Molekülstruktur der monoklinen Phase von 1.3-Di-tert-butyl-2.2-dimethyl-1.3.2.4λ2 -diazasilastannetidin / The Crystal and Molecular Structure of the Monoclinic Phase of 1,3-Di-feri-butyl-2,2-dimethyl-1,3,2,4λ2 -diazasilastannetidine

Abstract

The crystal and molecular structure of the monoclinic phase of 1,3-di-tert-butyl-2,2-dimethyl-1,3,2,4λ² -diazasilastannetidine has been determined from three-dimensional X-ray data collected on a two-circle diffractometer at -120 °C (MoKa radiation, 2623 reflexions, R - 0,050). The crystals are monoclinic, space group C2/c, with cell dimensions a = 10.655(5), b = 25.75(1), c = 17.33(1) Å, β = 106.8(1)° and Z = 12. Four monomeric (crystal site symmetry 2 (C₂)) and four dimeric units (crystal site symmetry 1̄ (C_i)) are present in the structure interacting over tin-tin (3.68 Å). Remarkable are the very short Sn-N bond (2.09 Å) in the monomer and the donation bond Sn-N (2.39 Å) in the dimer. The coordination of the tin atoms in the different units is discussed in detail.