Synthesis, crystal structure, and spectroscopic characterization of the borazine derivatives [B{CH2(SiCl3)}NH]3 and [B{CH2(SiCl2CH3)}NH]3

The borazine derivatives B,B',B-tris[(trichlorosilyl)methyl]borazine [B{CH2(SiCl3)}NH](3) (1), and B,B',B-tris[{dichloro(methyl)silyl}methyl]borazine [B{CH2(SiCl2CH3)}NH](3) (2) were prepared by reacting (Cl3Si)CH2(BCl2) (3) and [Cl-2(CH3)Si]CH2(BCl2) (4) with hexamethyldisilazane (hmds), respectively. Both compounds, 1 and 2 crystallize in space group R3c with a = 1712.53(4), c = 1230.33(4) pm, Z = 6, R-1 = 0.030, and a = 1713.8(2), c = 1258.7(2) pm, Z = 6, R-1 = 0.034, respectively. According to the single crystal X-ray diffraction analyses, the title compounds show a planar B3N3 six-membered ring with B-N distances of 142.3(3) pm (point symmetry C-3) and synfacial oriented substituents. The borazine derivatives have also been characterized by NMR and IR spectroscopy as well as by MS spectrometry.