E. A. Grebneva

Reaction of phenyltrifluorosilane and phenyl(hydrocarbyl)difluorosilanes with bis(2-hydroxyethyl)-and tris(2-hydroxyethyl)amine and their N-methyl and O-trimethylsilyl derivatives. A novel route to quasisilatranes

Reaction of phenyltrifluorosilane, diphenyldifluorosilane, and methylphenyldifluorosilane with bis(2-hydroxyethyl)amine, methyl-bis(2-hydroxyethyl)amine, methyl-bis(2-trimethylsiloxyethyl)amine, leads to 1,3-dioxa-6-aza-2-silacyclooctane derivatives, (N → Si) quasisilatranes: 1,1-difluoroquasisilatrane, 1-phenyl-1-fluoro-5-methylquasisilatrane, or 1-methyl-1-fluoroquasisilatrane, containing the donor-acceptor bond N → Si and pentacoordinate silicon atom. 1-Phenylsilatrane was found to be the product of the reaction of phenyltrifluorosilane with tris(2-trimethylsiloxyethyl)amine, whereas with tris(2-hydroxyethyl)amine 1-phenylsilatrane and 1-fluorosilatrane were formed in the molar ratio of 3:1. The structure of the synthesized compounds was proved by 1H, 13C, 15N, 19F, 29Si NMR and IR spectroscopy.

The unusual reaction of phenyltrifluorosilane with 2-aminoethanol and its N-methyl derivatives

139 In the course of study of the C–Si bond cleavage in phenyltrifluorosilane (PTS) with the aim of using PTS in the synthesis of organoelement compounds [1–6], we studied the reaction of PTS with 2-aminoethanol and its Nmethyland N , N -dimethyl derivatives. Previously, we found that the reaction of protodesilylation of PTS with 8-hydroxyquinoline or 8-mercaptoquinoline leads to new intracomplex heterocyclic compounds, (N Si) 8-(trifluorosiloxy)quinoline or (N Si) 8-(trifluorosilylthio)quinoline, containing a pentacoordinated silicon atom [3] (reaction 1): (1)

Reaction of tetrafluorosilane with tris(2-hydroxyethyl)amine, tris(2-trimethylsiloxyethyl)amine and bis(2-trimethylsiloxyethyl)amine and its N-methyl derivative. 1,1-difluoroquasisilatranes

Reaction of tetrafluorosilane with tris(2-hydroxyethyl)-and tris(2-trimethylsiloxyethyl)amine results in formation of 1-fluorosilatrane and fluorosilatrane in 75 and 53% yield, respectively. Reaction of tetrafluorosilane with bis(2-trimethylsiloxyethyl)amine and its N-methyl derivative leads to the hitherto unknown 1,1-difluoroquasisilatranes (N → Si) F2Si(OCH2CH2)2NR (R = H, Me) containing donor-acceptor bond N → Si and pentacoordinate silicon atom. The structure of the synthesized compounds was proved by 1H, 13C, 15N, 19F, 29Si NMR and IR spectroscopy.

Synthesis and structure of (C=O→Si←O′=C′)bis(2-methyl-4-oxopyran-3-yloxy)difluoro-(λ6)siliconium

A new six-coordinate silicon compound, (C=O→Si←O′=C′)bis(2-methyl-4-oxopyran-3-yloxy)-difluoro(λ6)siliconium, containing two five-membered rings closed by C=O→Si coordination bonds, forms o protodesilylation trifluoro(phenyl)silane with 3-hydroxy-2-methylpyran-4-one (maltol). According to multinuclear NMR and IR spectral data and quantum-chemical calculations, the silicon atom in this compound has an octahedral environment with two cis-arranged C=O→Si bonds

Phenyltrifluorosilane in organoelemental and organic synthesis

Ways of phenyltrifluorosilane application in organoelementalal and organic synthesis are summarized and systematized for the first time. The methods of its synthesis, physicochemical properties, and reactivity are considered. Special attention is paid to the original experimental results obtained by the authors.

New heterosilocanes, 1,1-difluoroand 1-phenyl-1-fluoro-2,8-dioxa-5-chalcogenosilocanes

The earlier unknown Si-fluorinated 2,8-dioxa-5-chalcogenosilocanes RFSi(OCH2CH2)2Y (R = Ph, F; Y = O, S) were synthesized. According to calculations, there is a weak transannular coordinate interaction Y→Si (Y = O, S), which is much weaker than that in the isostructural quasisilatranes (Y = N). At low temperatures, 1,1-difluoro-2,5,8-trioxasilocane forms a dimer, in which two molecules of the monomer are linked by four fluorine bridges Si-F→Si located in pairs in the two orthogonal planes SiF2Si.

1-(pyridine-2-carboxymethyl)silatrane

1-(N-Heterylalkyl)silatranes Het(CH2)nSi(OCH2CH2) 3N and their physical and chemical properties have been systematically studied by us since the beginning of the nineteen nineties [1–3]. Generally, they are obtained by the reaction of transetherification of the corresponding (N-heterylalkyl)trialkoxysilanes with tris(2-hydroxyethyl)amine [2, 4]. connecting the heterocycle with the silicon atom of the silatranyl group.

Boratrane Method of Silatrane Synthesis

It has been reported earlier [1, 2] that the transesterification of boratrane B(OCH2CH2)3N and its Сderivatives with triethoxysilane in the presence of aluminum alkoxylate affords 1-hydroxysilatran and its С-derivative [Eq. (1)]. Magnesium propoxide [3] or AlCl3 also were used as a catalyst [4]. In the absence of a catalyst the reaction occurs more slowly. An attempt to synthesize 1(2-chloroethyl)silatrane through this way (1) failed [5].

New route to 1,1-difluoro-5-methylquasisilatrane

A new route to 1,1-difluoro-5-methylquasisilatrane (N→Si) F2Si(OCH2CH2)2NMe is elaborated: the reaction of chlorinated methyltrifluorosilanes F3SiCH3−nCln (n = 1–3) as well as trifluoro(3-chloropropyl) silane and trifluoro(propenyl)silane with N-methyl-bis(2-hydroxyethyl)amine. The reactivity of the silanes F3SiCH3−nCln increases with the number of chlorine atoms, that is, with the electronegativity of the CH3−nCln group.