Germanium Organometallics

Heavier element-containing aromatics of [4n+2]-electron systems

“…The formation and properties of germacyclopropene has been extensively studied and its σ*-aromaticity was examined by theoretical calculations. 290 In 1985, the Egorov group reported the first example of germacyclopropene (germirene), which possess typical C=C double bond [1.331( 9) Å] but the C-Ge [1.929(6)/1.915( 6) Å] bonds that are shorter than the standard C-Ge bond [1.96-2.01 Å], implying the aromatic character of the C2Ge ring. 291 In 2016, the Baumgartner and Marschner group demonstrated the reaction of disilylated germylene phosphine adduct 6-4-1 with DPA to afford germacyclopropene a3CGe1 (Scheme 6-4).…”

Mono‐ and Bilayered Lead(II)–bpno Polymers with Unusual Low Energy Emission Properties (bpno = 4,4'‐Bipyridine N,N'‐Dioxide)

“…Thus, we were interested in continuing our research without the addition of dca to see if the same structure of the Pb1 grid in 1 could be obtained. However, the result seems to be quite unexpected, and a novel structure of 2 was produced (Figure 4), in which the Pb atom is eight-coordinate with two chelating NO 3 -ions, three bpno ligands, and one water molecule. Although the Pb 2 (μ-4,4,4Ј-bpno) 2 unit is again found in this structure, except for the absence of two bpno ligands (contrasted with 1), the extended structure only leads to a monolayer topology with the dimensions of a rhombus grid 13.814 × 13.814 Å ( Figure 5).…”

“…As shown in Figure 1a, Pb1 is in an eight-coordinate environment, surrounded only by O atoms, of which five are from bpno ligands, two from a bidentate NO 3 -and one from a monodentate NO 3 -group. The dca ligand is not involved in the Pb1 motif but is in the Pb2 part ( Figure 1b).…”

“…As far as the intrinsic appeal of Pb 2+ is concerned, the presence of an 6s 2 outer electron configuration not only leads to interesting topological arrangements, [3] but also plays an important role in the luminescence action of the complex.…”