Germanium Complexes with 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) []H and 2,6-pyridinobis(1,2-phenols) []H (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.

Oligoorganogermanes: Interplay between Aryl and Trimethylsilyl Substituents.

Derivatives of main group elements containing element-element bonds are characterized by unique properties due to σ-conjugation, which is an attractive subject for investigation. A novel series of digermanes, ArGe-Ge(SiMe), containing aryl (Ar = -CHMe (), -CHF (), CF ()) and trimethylsilyl substituents, was synthesized by the reaction of germyl potassium salt, [(MeSi)GeK*THF], with triarylchlorogermanes, ArGeCl. The optical and electronic properties of such substituted oligoorganogermanes were investigated spectroscopically by UV/vis absorption spectroscopy and theoretically by DFT calculations.

Theoretical analysis of glyoxal condensation with ammonia in aqueous solution.

The reactions of glyoxal with ammonia, ammonium salts, and amines cause the formation of the secondary organic aerosol (SOA) components (imidazole and its derivatives) in the atmosphere. The interaction of glyoxal and ammonia in aqueous solution is a primary reaction for these processes, and the explanation of its mechanism will allow developing the methods to control the formation of the SOA components. A detailed mechanism for the formation of key intermediates, namely, ethanediimine, diaminoethanediol, and aminoethanetriol, required for the imidazole ring cyclization, is proposed, and its potential energy surface (PES) has been constructed.

Oligothienyl catenated germanes and silanes: synthesis, structure, and properties.

The synthesis of two new groups of oligothienyl catenated silanes and germanes, Me5M2Thn (1a-b), Me5M2ThnM2Me5 (2a-c) (terminal), and ThnM2Me4Thn (3a-d) (internal) (M = Si, Ge; n = 2, 3; Th = 2- or 2,5-thienyl), is reported. The study of their structural parameters as well as of their spectral (NMR), electrochemical (CV) and optical (UV/vis absorbance, luminescence) properties has been performed in detail; in addition, the unexpected compound [Th2Si2Me4Th]2 (3a') is also studied. Theoretical investigations have been performed for model compounds in order to establish structure-property relationships.

Acetaldehyde-Ammonia Interaction: A DFT Study of Reaction Mechanism and Product Identification.

The product of acetaldehyde and ammonia reaction, namely, 2,4,6-trimethyl-1,3,5-hexahydrotriazine trihydrate, was synthesized and identified using a combination of experimental (NMR spectroscopy, IR spectroscopy, melting point determination) and DFT-based theoretical approaches. A reaction mechanism was proposed. The reaction was shown to proceed via the formation of aminoalcohol, imine, and geminal diamine intermediates accompanied by cyclization of these species.

New oligogermane with a five coordinate germanium atom: the preparation of 1-germylgermatrane.

The first example of an oligogermane, N(CH2CH2O)3Ge-Ge(SiMe3)3 (1), containing a hypercoordinate germanium atom was prepared and characterized by various methods (NMR, UV/vis, and X-ray analysis). The electronic structure of compound 1 was investigated via DFT calculations.

DFT investigation of the thermodynamics and mechanism of electrophilic chlorination and iodination of arenes.

Quantum chemical calculations at the B3LYP/6-311G level have been carried out in order to investigate the reaction mechanisms of the iodination of benzene and its monosubstituted derivatives with ICl, I(+), I (3) (+) and reagents containing N-I and O-I bonds as the iodinating agents. The results are compared with those obtained for chlorination by Cl(+) and Cl(2), both in the gas phase and in methanol solution using the PCM solvent model. We have also used the MP2/DGDZVP level of theory and the IEFPCM model to perform comparisons in a few cases.