Monomeric bivalent group 4B metal dialkylamides M[NCMe2(CH2)3CMe2]2(M = Ge or Sn), and the structure of a gaseous disilylamide, Sn[N(SiMe3)2]2, by gas electron diffraction

Abstract

Reaction of Li[[graphic omitted]Me₂](LiNR₂) in n-C₅H₁₂ at 20°C with GeCl₂·dioxan or SnCl₂ affords the corresponding coloured crystalline diamagnetic metal(II) dialkylamide, M(NR₂)₂, which is monomeric (cryoscopy in C₆H₁₂), has a low first ionisation potential (6·90 eV for M = Ge, 6·80 eV for M = Sn), and furnishes the 2,2,6,6-tetramethylpiperidyl radical :NR₂ upon photolysis; electron diffraction analysis of gaseous Sn[N(SiMe₃)₂]₂ shows only the monomer at ca. 100°C and 10^–2 atm, which has C_2v symmetry, ∠NSnN = 96·0°, and Sn–N (av.)= 2·09 Å.