STRUCTURAL STUDIES OF THE MONOMERIC, LOW-COORDINATE, INDIUM AMIDES (T-BU)2INN(2,6-I-PR2C6H3)SIPH3 AND IN(N(SIME3)2)3

This paper describes the characterization and structure of (t-Bu)2InN( 2,6-i-Pr2C6H3)SiPh3, 1 and the structure of In{N(SiMe3)2}3, 2. These c ompounds were synthesized by a salt elimination reaction between di-te rt-butylindium chloride or indium chloride and the appropriate lithium amide. They were characterized by variable temperature H-1 NMR spectr oscopy (1) and X-ray crystallography (1 and 2). In the solid state 1 a nd 2 have planar coordination at indium and nitrogen. The In-N bond le ngths, 2.104 (3) angstrom (1) and 2.049 (1) angstrom (2) are relativel y short in comparison to the sum of atomic radii of indium and nitroge n. This shortening may be accounted for in terms of an ionic contribut ion to the In-N bond rather than by the presence of significant In-N p -p pi-bonding. Crystal data with MoKalpha (lambda = 0.71069 lambda) at 130 K : 1, C38H50InNSi, a = 10.437 (4) angstrom, b = 10.788 (6) angst rom, c = 18.269 (5) angstrom, alpha = 98.61 (4)degrees, beta = 95.43 ( 3)degrees, gamma = 118.85 (3)degrees, triclinic, space group P1BAR, Z = 2, R = 0.055; 2, C18H54InN3Si6, a = 16.214 (4) angstrom, c = 8.343 ( 4) angstrom, trigonal, space group, P31cBAR, Z = 2, R = 0.029.