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The hydrosilylation reactions of allylgermanes R3GeAll (R3 = Cl3, Me3) in the presence of a platinum catalyst (Karstedt catalyst) with methylchlorohydridesilanes MenCl3–nSiH (n = 0–2) and 1,1,3,3-tetramethyldisiloxane have been studied. It was found that only 1,3-adducts are formed. In some cases, the replacement of only one methyl group at silicon with Cl (or vice versa, Cl for methyl group) leads not only to a decrease in the yields of the products obtained, but to a complete absence of reaction. A possible route of the studied reactions is proposed. The identification of the synthesized compounds was carried out using the methods of gas-liquid chromatography, 1H NMR spectroscopy and chromatography-mass spectrometry.

The effect of the reactant ratio in the reaction of tetramethyldisiloxane with germanium tetrachloride and diethyl ether on the structure and reactivity of the resulting trichlorogermane–diethyl ether complexes was studied, and the products were reacted with 1,1,3,3-tetramethyl-1,3-divinyldisiloxane. The hydrogermylation of 1,1,3,3-tetramethyl-1,3-divinyldisiloxane with trimethylgermane in the presence of Karstedtʼs catalyst afforded exclusively the corresponding anti-Markovnikov adducts at one and two double bonds of the substrate.

Previously, it was shown that the presence of bulky silicon-containing substituents in the monomer unit of metathesis polynorbornenes hinders the postmodification and, in particular, exhaustive gem-difluorocyclopropanation of main-chain double bonds. In order to reduce the double bonds shielding by substituents, a new polynorbornene with a dimethylsilacyclopentane fragment in the monomer unit, poly(4,4-dimethyltricyclo[5.2.1.02,6]-4-siladec-8-ene) (PNBCP), is synthesized, in which the silylmethyl group is moved further from the double bonds. In order to achieve this, the monomer 4,4-dimethyltricyclo[5.2.1.02,6]-4-siladec-8-ene (NBCP) is first obtained via the diene condensation of 1,3-cyclopentadiene and 1,1-dichlorosilacyclopent-3-ene with following methylation of Si-Cl bonds. NBCP is polymerized by the ring-opening metathesis scheme in the presence of the first-generation Grubbs catalyst, Cl2(PCy3)2Ru=CHPh. The new polymer PNBCP is obtained in a yield of 99–100% and characterized. The gem-difluorocyclopropanation of PNBCP with difluorocarbene, generated during the thermolysis of sodium chlorofluoroacetate, is studied; the conditions for exhaustive replacement of double bonds by gem-difluorocyclopropane are found. It is shown that PNBCP is more active in postmodification compared to poly(5-trimethylsilyl)norbornene but is less active than unsubstituted polynorbornene. It is demonstrated that the introduction of the silacyclopentane fragment into the monomer unit of the metathesis polynorbornene and its subsequent difluorocyclopropanation lead to increase in gas permeability and diffusion and cause a slight decrease in ideal separation selectivities. It is found that gem-difluorocyclopropanation increases the glass transition temperature of PNBCP by 60°C and makes its films stable when stored in air.

The application of organogermanium compounds (OGCs) to the creation of biologically active medicines with unique properties that possess a wide range of pharmacological actions, including the series of Panaxel drugs and Germavit mineral vitamin complex, is considered. Based on OGC, novel biologically active materials for medical technology were developed: dental flosses, retention surgical suture, bandages, and other products. The biological activity of OGC also allows to use them in perfumery and cosmetics industries. The methods for the synthesis of organogermanium compounds are described.

The results of studies carried out in the past five years on the gas-phase synthesis of organochlorosilanes, pentachlorodisiloxanes, organochlorogermanes, and organochlorostannanes at 400–550 °C in the presence of hexachlorodisilane or 1,1-dichloro-1-silacyclopent-3-ene as sources of dichlorosilylene are summarized.

Results of the investigations in recent years on the gas phase thermal reactions of both inorganic and organic silylenes have been correlated. Particular attention has been paid to the sources used for generation of these unstable intermediates and also to methods of obtaining and to the properties of cyclic silylenes. The bibliography contains 62 references.

Results of the investigations in recent years on the gas phase thermal reactions of both inorganic and organic silylenes have been correlated. Particular attention has been paid to the sources used for generation of these unstable intermediates and also to methods of obtaining and to the properties of cyclic silylenes. The bibliography contains 62 references.

1. A study has been made of the mass spectra of tricarbonyliron complexes of 1-sila-2,4-cyclohexadiene with various substituents on the silicon atom. 2. The main route of fragmentation of the tricarbonyliron complexes under electron impact is successive decarbonylation with subsequent elimination of an HR molecule with the participation of the iron atom. 3. Structures have been proposed for the ions C5H5SiRFe+, C5H5Si+, and C3H3Si+. In the decomposing C5H5SiRFe+ ions, interaction of the iron atom with the silicon atom takes place, whereas the nondecomposing ions probably have the structure of coordinated silabenzene. A pyramidal structure of the nido-cluster type is ascribed to the C5H5Si+ and C3H3Si+ ions.

Calculations of the radical anions of a number of aryl-containing organosilicon compounds, viz., trimethylphenylsilane, 1,2-disilaacenaphthene, 1-methyl-1-phenyl-silacyclobutane, and 1,1-dimethyl-1-silaindene, have been carried out by the INDO in the Benson-Hudson parametrization. The constants of the hyperfine structures in the ESR spectra of the radical anions of 1,2-disilaacenaphthene and 1,1-dimethyl-1-silaindene have been assigned on the basis of the results of the calculations.

1. Sulfur atoms are inserted into the olefinic double bond in the reaction of S8 with 1, 1-dimethylsila-3-cyclopentene in the presence of Fe3(CO)12 to form cyclic and crosslinked polysulfides as well as a diironhexacarbonyl dithiolane complex. 2. An x-ray diffraction structural analysis was carried out for 1-dimethylsila-4,5,6,7-tetrathiabicyclo[4. 3. 0]nonane.

On the basis of the EPR spectra of the anion-radicals of 1,2-bis-(trirnethylsilyl)benzene, 9,9,10,10tetrarnethyl-9,10-disila-9,10-dihydroanthracene, and 9,10-disila-9,10-dihydroanthraeene, it has been concluded that there is insufficient justification for the idea, encountered in the literature, that delocalization of the unpaired electron between the two aromatic fragments in 9,9,10,10-tetrarnethyl-9,10-disila-9,10-dihydroanthracene is possible. The five-component EPR spectrum assigned to the anion-radicals of this compound may, in actual fact, belong to the anion-radicals of products of the splitting of this compound, of the same type as the organosilicon derivatives of diphenyl. The EPR spectra of the anion-radicals of ortho-trirnethylsilyltoluene, 9,9-dirnethyl-9-sila-9,10-dihydroanthraeene, and 9-sila-9,10-dihydroanthraeene indicate that when 9,9-dirnethyl-9-sila-9,10dihydroanthracene is reduced, it is converted into an organosilicon ketone. It is suggested that oxidation takes place through a stage involving the formation of the dianion-radical.

In the 1-sila-2, 8-dioxa-5-methyl-5-azacyclooctane-spiro-1′-silaacenaphthene molecule, as a result of the formation of an intramolecular donor-acceptor bond Si-N, the coordination number of the Si atom is increased to 5.

Die Reaktion von Lepidin (I) mit einem zweifachen Uberschus von Trichlorsilan (II) bei 680°C liefert in 33%iger Ausbeute 1,1-Dichlor-1-sila-5-aza-acenaphthen (III) als kristalline, hygroskopische Substanz.

Workup of the mixture of products of pyrolysis of cyclotetrasiloxane (Me2SiO)2(MePhSiO)2 yielded 1,3- (I) and 1,5-(o-phenylene)cyclosiloxane (II), the structures of which were established on the basis of data from their IR, PMR, and mass spectra.