The crystal and molecular structure of sesqui(acetamide)(diacetamide) (perchlorato)lithium(I)

✍ Scribed by P.S. Gentile; J.G. White; D.D. Cavalluzzo

• Publisher: Elsevier Science
• Year: 1976
• Tongue: English
• Weight: 440 KB
• Volume: 20
• Category: Article
• ISSN: 0020-1693
• DOI: 10.1016/s0020-1693(00)94087-8

✦ Synopsis

The structure of sesqui(acetamide)(diacetamide) (perchlorato)lithium(Z), Li(CH3CONH2) ttj2 (CHJ

CONHCOCH3ClOz,, has been determined from three-dimensional X-ray data. The unit cell is orthorhombic, space group Fdd2, having dimensions a = 13.742(S)& b = 50.69(l)& c = 7.8.54(Z)& and Z = Z6. The intensity data were collected on an Enraf-Nonius CAD-4 automated diffractometer using monochromatic CuK, radiation. The structure was determined by the heavy atom method and refined anisotropically to a conventional unweighted R-factor of 0.087.

The compound is a structural dimer and contains octahedral lithium. The lithium ion is coordinated to six oxygens, two from the diacetamide, one from the perchlorate ion, and three from acetamides. The acetamide oxygens form bridges between two lithium ions. The coordination sphere about each lithium is a distorted octahedron, and the dimer consists of two of these octahedra having a face in common. Zntermolecular hydrogen bonds exist between the diacetamide nitrogen and a perchlorato oxygen, linking the molecules in a three-dimensional network. Lithiumoxygen bond distances are 1.99-2.Z6A

for the diacetamide and acetamide oxygens and 2.77A for the perchlorato oxygen. The Li-Li distance is 2.74& indicating metal-metal interaction.