The Formal Conversion of SiOH Protons into Hydrides by Germanium(II) Species Leads to the Formation of the Germanium(IV) Hydride Cluster [(RSiO3GeH)4]

Germanium Complexes with ONO Tridentate Ligands: O-H Bond Activation Control According to DFT Calculations

Polydentate ligands are used for thermodynamic stabilization of tetrylenes-low-valent derivatives of Group 14 elements (E = Si, Ge, Sn, Pb). This work shows by DFT calculations how the structure (the presence or absence of substituents) and type (alcoholic, Alk, or phenolic, Ar) of tridentate ligands 2,6-pyridinobis(1,2-ethanols) [^AlkONO^R]H₂ and 2,6-pyridinobis(1,2-phenols) [^ArONO^R]H₂ (R = H, Me) may affect the reactivity or stabilization of tetrylene, indicating the unprecedented behavior of Main Group elements. This enables the unique control of the type of the occurring reaction. We found that unhindered [ONO^H]H₂ ligands predominantly led to hypercoordinated bis-liganded {[ONO^H]}₂Ge complexes, where an E(+2) intermediate was inserted into the ArO-H bond with subsequent H₂ evolution. In contrast, substituted [ONO^Me]H₂ ligands gave [ONO^Me]Ge: germylenes, which may be regarded as kinetic stabilized products; their transformation into E(+4) species is also thermodynamically favorable. The latter reaction is more probable for phenolic [^ArONO]H₂ ligands than for alcoholic [^AlkONO]H₂. The thermodynamics and possible intermediates of the reactions were also investigated.

Molecular Main Group Metal Hydrides

This review serves to document advances in the synthesis, versatile bonding, and reactivity of molecular main group metal hydrides within Groups 1, 2, and 12-16. Particular attention will be given to the emerging use of said hydrides in the rapidly expanding field of Main Group element-mediated catalysis. While this review is comprehensive in nature, focus will be given to research appearing in the open literature since 2001.

Synthesis of Bifunctional Silsesquioxanes and Spherosilicates with Organogermyl Functionalities

In this paper we present the synthesis of mixed bifunctional compounds of T₈ H₈ silsesquioxane and spherosilicate (HSiMe₂ O)₈ Si₈ O₁₂ derivatives via platinum-catalyzed hydrosilylation of alkenylgermanes and olefins. To the best of our knowledge, this is the first literature example of bifunctional compounds with organogermyl functionalities. Eleven mixed systems with a variety of substituents (Si-H, alkyl, germyl, epoxy, and hydroxy) were prepared and fully characterized by NMR spectroscopy. Additionally, our research includes a real-time FT-IR study of the synthesis of these bifunctional compounds of the general formula (R)_8-m (GeR'₃ (CH₂ )_n+2 R)_m Si₈ O₁₂ . and (R''(CH₂ )₂ R)_8-m (GeR'₃ (CH₂ )₂ R)_m Si₈ O₁₂ where m∼4.

Dialkenylgermanes as Precursors of Silsesquioxane-based Macromolecular Structures

Herein we report a study of highly efficient platinum-catalyzed hydrosilylation of dialkenylgermanes with silsesquioxanes and spherosilicates. The use of divinyl- and diallylgermanes allowed the synthesis of new classes of compounds, i. e., dumbbell-type systems, silsesquioxanes with alkenyl pendant group, and oligomeric derivatives. The results are supported by detailed data from in situ FT-IR and NMR measurements, enabling precise monitoring of the reaction progress and determination of regioselectivity of the formed products.

Synthesis and Characterization of Germanium Coordination Compounds for Production of Germanium Nanomaterials

A series of novel germanium(II) precursors was synthesized to initiate an investigation between the precursors' structures and the morphologies of the resulting nanoparticles. The precursors were synthesized from the reaction of Ge[N(SiMe3)2]2 or [Ge(OBut)2]2 and the appropriate ligand: N,N'-dibenzylethylenediamine (H2-DBED), tert-butanol (H-OBut), 2,6-di-methyl phenol (H-DMP), 2,6-di-phenyl phenol (H-DPP), tert-butyldimethylsilanol (H-DMBS), triphenylsilanol (H-TPS), triphenylsilanethiol (H-TPST), and benzenethiol (H-PS). The products were identified as: [Ge(μc-DBED)]2 (1, μc= bridging chelating), [Ge(μ-DMP)(DMP)]2 (2), Ge(DPP)2 (3), [Ge(μ-OBut)(DMBS)]2, (4), [Ge(μ-DMBS)(DMBS)]2 (5), Ge(TPS)3(H) (6), [Ge(μ-TPST)(TPST)]2 (7), and Ge(PS)4 (8). The Ge(II) metal centers were found to adopt a pyramidal geometry for 1, 2, 4, 5, 7, a bent arrangement for 3, and a tetrahedral coordination for the Ge(IV) species 6 and 8. Using a simple solution precipitation methodology, Ge(0) nanomaterials were isolated as dots and wires for the majority of precursors. Compound 7 led to the isolation of amorphous GexSy. The nanomaterials isolated were characterized by TEM, EDS, and powder XRD. A correlation between the precursor's arrangement and final observed nanomorphology was proffered as part of the 'precursor structure affect' phenomenon.

Synthesis of an Aluminum Spirocyclic Hybrid with an Inorganic B2O3 and an Organic C3N2 Core

The reaction of LAl (L = HC(CMeNAr)2, Ar = 2,6-iPr2C6H3) or LAlH2 with PhB(OH)2 yields the unprecedented spirocyclic LAl[(OBPh)2O] compound. The former reaction proceeds under hydrogen formation and simultaneous oxidation of the aluminum(I).