Synthesis of dimethylditritiogermane Me<Subscript>2</Subscript>GeT<Subscript>2</Subscript>

A microsynthetic procedure for preparing tritium-labeled alkyl-substituted germanes is developed. The resulting dimethylditritiogermane can be used as a source of dimethylgermylium ions. The synthesis was performed by the reduction of dibromodimethylgermane with lithium tritide in presence of AlBr₃.     

Radiochemical Study of Reactions of Diethylsilylium Ions with Dibutyl Ether in the Gas and Liquid Phases

Reactions of diethylsilylium ions with dibutyl ether in the gas and liquid phases were studied radiochemically. These reactions, as those with benzene and alcohols, are accompanied by partial rearrangement of diethylsilylium ions into monoethylsilylium and dimethylsilylium ions. The extent of transformations of the (C₂H₅)₂SiT⁺ ions decreases in going from benzene to dibutyl ether, which is due to the higher energy of adduct formation with the ether, compared to benzene.     

Ion-Molecular Reactions of Diethylsilylium Ions with Alcohols in the Gas Phase

Radiochemistry was used to study reaction of tritium-labeled diethylsilylium ions with alcohols in the gas phase. The reaction involves both rearrangement of the diethylsilylium ions and isomerization of the substituent in the substrate. The hydroxyl hydrogen of the alcohol and the tritium atom of the diethyl-silylium ion undergo exchange which, however, is less vigorous that in the case of the monoethylsilylium ion. A possible reaction mechanism is proposed.     

Radiochemical study of interaction of the nucleogenic diethylgermylium cations with benzene in the gas and condensed phases

Interaction of free diethylgermylium ions with benzene in the gas and condensed phases was studied by the radiochemical method. A possible mechanism of the ion-molecular reactions was suggested. At the interaction of these ions with benzene the products of germylation of the latter were not detected. More advantageous are the processes of degermylation leading to the formation of tritium-labeled benzene. A possibility of rearrangement of the nucleogenic diethylgermylium cation into other isomeric forms was revealed, these forms were calculated by B3LYP method with the 6–31G* and cc-pVTZ basis sets.     

Radiochemical investigation of the interaction of nucleogenic diethylgermylium ions with methyl <Emphasis Type="Italic">tert</Emphasis>-butyl ether

Radiochemical method was used in the study of the interaction of free diethylgermylium cations with methyl tert-butyl ether in the gas and condensed phases, and the mechanisms of the relevant ion-molecular reactions were proposed. The most probable pathways of the (C₂H₅)₂TGe⁺ cation transformation into other isomeric forms are shown as a result of B3LYP calculation with cc-pVTZ basis set.     

Synthesis of Phenylsilane Doubly Tritium-labeled in the Benzene Ring

Russian Journal of General Chemistry -     

Interconversion of Silylphenyl and Phenylsilyl Cations in the Reaction with Benzene

The possibility for positive charge migration in SiC₆H ₇ ⁺ cation from carbon to silicon (or vice versa) was studied by the radiochemical method. Silylphenyl cation with initial charge localization on the carbon atom is transformed into phenylsilylium ion where the positive charge is localized on the silicon atom. No migration of positive charge from the silicon atom to carbon occurs.     

Germanium analogs of carbenium ions

The review summarizes advances in the production of germanium analogs of carbenium ions both per se in solutions and crystals and as intermediates in reactions of organogermanium compounds. The data on the structures of germylium cations of different types are considered. Emphasis is given to the reactivity of germylium ions and their ion-molecule reactions with nucleophilic reagents in the gas and condensed phases.     

Gas phase reaction of nucleogenic dimethylgermylium cations with benzene

Reaction of nucleogenic dimethylgermylium cations with benzene in the gas phase was studied by the radiochemical method. The formation of the products of germylation of benzene, dimethylphenylgermane, and phenylgermane is indicative of the formation of dimethylgermylium cations by the β-decay of tritium in the molecule of dimethylditritium germane. Dimethylgermylium cations are shown to undergo a rearrangement in the course of the reaction with benzene, which is consistent with the earlier results of quantum-chemical calculations.     

Radiochemical Study of the Reactions of Diethylsilylium Ions with Hexamethyldisilazane and Isobutylamine in the Gas Phase

Ion-molecule reactions of diethylsilylium ions with hexamethyldisilazane and isobutylamine were studied radiochemically. These reactions, like the previously studied reactions of diethylsilylium ions with tert-butylaminotrimethylsilane, occur exclusively along the condensation pathway; in both cases, the diethylsilylium ion undergoes a rearrangement. The extremely low degree of rearrangement of the diethylsilylium ion and high yield of the labeled substrate in the reaction with isobutylamine are due to the presence of two labile N-H hydrogen atoms, resulting in active isotope exchange between the Si-T tritium atoms and N-H hydrogen atoms and in shorter lifetime of the condensation complex, caused by more intense bimolecular deprotonation of the complex.