Synthesis and Characterization of Ethynylated Germa[4]pericyclyne

Abstract

This paper presents the synthesis and characterization of (TMS-ethynyl)-substituted germa [4]pericyclyne composed of acetylene moieties and germanium atoms. Characterization was performed by X-ray crystallography, UVvis absorption, and photoluminescence spectroscopy. DFT calculations suggested interactions between the side chain alkynes and the ringforming acetylenes through germanium vertex atoms. Keywords: Element-blocks | Germanium | PericyclynesResearch on polyacetylene materials has attracted increasing attention with the growing importance of "element-blocks" (functional nano building blocks composed of heteroatoms) for advanced electronic and optical materials.1,2 Skipped polyynes ([R 2 XC¸C] n ) have received particular interest as a versatile "element-block" due to their easy modification and tunability of their characteristics by choosing appropriate linker atoms (X). Specifically, recent reports reveal that by using group 14 heteroatoms like silicon, with smaller ionization energies than those of carbon, one can achieve electron delocalization (although usually, the conjugation is interrupted at the alkyne units), resulting in effective enhancement of electric and optical properties.4 Therefore, skipped polyynes are potential candidates for preparing functional materials such as semiconductors, ceramic precursors, and hole-transporting materials. 5We have studied the synthesis and properties of both acyclic and cyclic germylene-ethynylene materials containing germanium (Scheme 1).6 Having a smaller ionization energy than silicon, germanium also forms stronger bonds to sp-carbon compared to tin. Additionally, cyclic skipped Ge-polyynes, called germa [N]pericyclynes, display characteristic emission properties compared to acyclic molecules, due to the fixed conformations and through-bond/through-space interactions. Therefore, element-block polymers composed of germapericyclynes, which are expected to impart functionality superior to that provided by monomeric pericyclyne units, are a promising platform for the fabrication of unique optical materials. Polymeric pericyclyne materials with linear, branched, dendric, and spirocyclic forms can be designed, with each pericyclyne unit connected via alkyne bridges. Thus, to enable electronic delocalization across the alkyne units, it is necessary for the vertex atoms to mediate conjugation between the alkyne spacers. The existence of alkynealkyne interactions through Ge atoms in pericyclyne ring systems has been suggested in our previous investigations.6 Thus, exo-ethynylated pericyclynes could be expected to show exoendo and exoexo alkynes interactions, and would be suitable candidate monomer units for polypericyclynes. However, their optical properties along with their molecular orbitals have not been studied yet. To explore the unique character of germa[N]pericyclynes as polymer precursors, we herein disclose the synthesis of an ethynylated germa[4]pericyclyne for preliminary research on poly(germapericyclynes), and provide a discussion of its properties.Star...

Germanium‐Carbdiyne: A 3D Well‐Defined sp‐Hybridized Carbon‐Based Material with Superhigh Li Storage Property

“…As displayed in Figure a, the Ge‐CDY powders deliver a typical strong peak around 96.3 ppm, which is attributed by the sp‐C atoms in the alkyne bonds. [ 25 ] As the Raman spectrum (Figure 2b) shown, an obviously strong peak around 1692 cm −1 confirmed the acetylenic bonds in Ge‐CDY. [ 26 ] Besides, the peak appears at 398 cm −1 is assigned to the ‐Ge‐C‐ bond.…”

“…After quenching, extraction, and purification, the white product TEG was obtained with 32% yield. [25] Sixteen pieces of Cu foils (1910 cm 2 ) were sonicated successively in HCl (3M), water, ethanol, and acetone. After that, the pretreated Cu foils were dried in a two-necked flask with argon flow, then 120 mL pyridine was injected into the flask under argon, and then 70 mg TEG (0.4 mmol) in 30 mL pyridine was dripped into the mixture over 1 hour.…”

Synthesis of Ag(I)@Fum−Pr−Pyr−Benzimidazole and Its Optical and Catalytic Activities in Click Reactions

“…Notably, the click reaction yield enhances when the reaction temperature is about 70°C, in H 2 O as a solvent and when the time is raised. It was speculated that lowering temperature and the catalyst loading primarily affect the catalytic performance of the reaction, generating lower product yields in longer reaction times (Table 2, Entries [16][17][18][19]. The reaction proceeded rapidly, as exhibited, in different times 2, 5, 10, 15, 20, and 30 minutes, resulting in the isolation of the product in a yield of 91, 98, 98, and for all others 99 %, respectively.…”

“…[9][10][11] Detection and removal of heavy metal ions and toxic materials are pivotal from environmental points of view. [12][13][14][15][16][17] Many transition metal ions are included in diverse essential biological processes and vital elements in human health. [18] Among the metal ions, silver is one of the precious metal elements, which plays a crucial role as a catalyst, antimicrobial agent against a large number of bacteria, and anti-infective.…”

“…Also, transition metal ions could be anchored or coordinated with a good dispersion on the functioning surface of fumed‐silica and utilized as electroluminescent materials, semiconductors, and catalysts [9–11] . Detection and removal of heavy metal ions and toxic materials are pivotal from environmental points of view [12–17] . Many transition metal ions are included in diverse essential biological processes and vital elements in human health [18] .…”