Reactions of AIH(3)center dot NMe3 with nitriles: Structural characterization and substitution reactions of hexameric aluminum imides

Abstract

The reaction of AlH3.NMe3 with RCN proceeds with the evolution of trimethylamine and affords (HAlNCH2R)(6) (R = Ph (1), P-MeC6H4 (2), p-CF3C6H4 (3)). Compounds 1 and 3 are characterized by single-crystal structural analysis. Compound 1 reacts with Me3SiBr as well as with PhC=-CH to give (XAlNCH2Ph)(6) (X = Br (4), PhCequivalent toC (5)). Structural data and other characterization data of compounds 4 and 5 show that all the hydridic hydrogen atoms in I have been replaced by bromine atoms and PhCequivalent toC groups, respectively. Compounds 1-5 are potential precursors for the preparation of aluminum nitride. Crystals of 1 are rhombohedral, space group R (3) over bar, with a = 15.7457(13) Angstrom, b = 15.7457(13) Angstrom, c = 14.949(2) Angstrom, V = 3209.8(5) Angstrom(3), and Z = 3, Crystals of 3. 3/4 C7H8 are triclinic, space group P (1) over bar, with a = 17.527(11) Angstrom, b = 18.894(12) Angstrom, c = 19.246(15) , alpha = 96.11(7)degrees, beta = 102.23(4)degrees, gamma = 106.79(3)degrees, V 5867(7) Angstrom(3), and Z = 4. Compound 4 crystallizes in the monoclinic space group P(2)1/c, with a = 14.175(4) Angstrom, b 16.678(5) Angstrom, c = 10.731(3) Angstrom, beta = 106.82(2)degrees, V = 2428.6(11) Angstrom(3), and Z = 2. Compound 5.C7H8 crystallizes in the monoclinic space group C2/c, with a = 25.842(5) Angstrom, b = 15.443(3) Angstrom, c = 20.699(4) Angstrom, beta = 105.88(3)degrees, V = 7945(3) Angstrom(3), and Z = 4.