Stable germylenes derived from 1,2-bis(arylimino)acenaphthenes

Metal exchange reactions of the magnesium complexes (dpp-BIAN)Mg(THF)(n), (dtb-BIAN)-Mg(THF)(n), and (bph-BIAN)Mg(THF)(n) with GeCl2(dioxane) afford the stable germylenes (dpp-BIAN)Ge (1), (dtb-BIAN)Ge(Et2O) (2), and (bph-BIAN)Ge (3), respectively (dpp-BIAN = 1,2-[(2,6-iPr(2)C(6)H(3))N](2)C12H6, dtb-BIAN = 1,2-[(2,5-tBu(2)C(6)H(3))N](2)C12H6, bph-BIAN = 1,2-[(2PhC(6)H(4))N](2)Cl2H6). Compound 1 is also obtained from (dpp-BIAN)Na-4 and GeCl4 in Et2O. The germylenes 1-3 were characterized by elemental analyses, H-1 NMR, C-13 NMR, and IR spectroscopy, and X-ray crystal structure analyses. In the monomeric molecules the two imino nitrogen atoms coordinate the germanium atom. The aryl(N) groups are arranged rather orthogonal to the acenaphthenediimine plane. Compound 3 shows an anti geometry with the ortho phenyl substituents of both N-phenyl rings positioned on opposite sides of the acenaphthenediimine plane. The bite angles N-Ge-N are 85.2degrees (1) and 85.0degrees (3), respectively. The Ge-N bond distances in 1-3 range from 1.878 to 1.915 Angstrom .