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The metathesis reaction of aluminum(III) dihydride LAlH 2 (1) (L = (ArNCMe) 2 CH, Ar = 2,6-i-Pr 2 C 6 H 4 ) with n-BuLi and n-Bu 2 Mg, respectively, resulted in di-n-butyl aluminum complex LAl(n-Bu) 2 (2). Meanwhile 1 reacted with MeLi producing dimethyl aluminum LAlMe 2 (3). Complexes 2 and 3 were characterized by NMR and elemental analysis, and 2 was additionally studied by single-crystal X-ray diffraction. The reported synthesis allows for access of dialkylaluminum complexes from aluminum-(III) dihydride compound (1) with excellent yields. The chemoselective double hydroboration of nitriles or single hydroboration of carbodiimides was studied with pinacolborane (HBpin) using LAl(n-Bu) 2 (2) as the precatalyst to afford bis(boryl)amines (4a−4m) and N-borylamines (6a− 6d) under solvent-free and mild conditions (60 °C). The records show that the catalytic reactions proceed in quantitative yields and short time. Moreover, nearly quantitative yield of di(boryl)(silyl)amine ( 5) was obtained, when cyanobenzene was reacted with equal amounts of HBpin and phenylsilane in the presence of precatalsyt 2. A comparison of the previously reported hydroboration reactions with nitriles in the literature and our results in the presence of the precatalyst LAl(n-Bu) 2 show convincingly the better results of short reaction time, mild reaction conditions, and quantitative yields.

The silicon atom in LSiCl or LSiMes (L = PhC­(NtBu)2, Mes = 2,4,6-Me3C6H2) inserts into the B–X bond of RBX2 (R = Ph, Mes, N­(SiMe3)2; X = Cl, Br), which is followed by the migration of the amidinate ligand and the halide atom. By this way, LB­(R)­SiCl3 (R = Ph, 2; Mes, 3; N­(SiMe3)2, 4) and LB­(R)­SiX2Mes (R = Ph, X = Cl, 5; R = Mes, X = Cl, 6; R = Mes, X = Br, 7) were obtained. Furthermore, a silylene–borane adduct LClSi → BPhCl2 (1) was obtained as an intermediate in the formation of compound 2. Compounds 2–7 are rare examples of borylhalosilanes.

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