• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.215-220
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• 2002

The structures of 1-fluorosilatrane and the silatranyl cation were calculated by Hartree-Fock (HF), Mofller-Plesset second order (MP2), and various density functional theory (DFT) methods using many different basis sets, demonstrating that the Si-N bonds in two species are quite different. The N${\rightarrow}$Si bond distance of 1-fluorosilatrane from the hybrid DFT calculations $({\sim}2.32{\AA})$ using the Perdew-Wang correlation functional agrees with the gas phase experimental value $(2.324{\AA})$, while other functionals yield larger distances. The MP2 bond distance (2.287${\AA}$ with 6-311$G^{\ast}$) is shorter, and the HF one (2.544 ${\AA}$ with 6-311$G^{\ast}$) larger than those of DFT calculations. The MP2 bond distance is in good agreement with experiment indicating that the electron correlations are crucial for the correct description of the N${\rightarrow}$Si interaction. The silatranyl cation is a stable local minimum on the potential energy surface in all methods employed suggesting that the cation could be a reaction intermediate. The Si-N bond length for the cation is about 1.87 ${\AA}$ for all calculations tested implying that the Si-N bond is mainly conventional. Bonding characteristics of the Si-N bond in two species derived from the natural bond orbital analysis support the above argument based on calculated bond lengths.

• Journal of the Korean Chemical Society
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• v.38 no.3
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• pp.241-245
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• 1994

The oxidative addition reaction has been employed to synthesize heteropolynuclear compounds containing Si-M bonding interaction between the silicon atom of silatrane, pentacoordinate silicon derivative with transannular Si-N dative bond, and the main group element. The reaction of $SnBr_2 with 1-bromosilatrane(1a) in acetonitrile gives the mixture of yellow(2a) and white(2b) solids which were isolated and charaterized by ^1H-NMR, ^{29}Si-NMR, ^{119}Sn-NMR and Mass spectroscopy. The yellow compound was characterized as 1-tribromotinsilatrane which had Si-Sn bonding interaction. The reaction of SnBr2 with 1-bromo-3,7,10-trimethylsilatrane(1b) in methanol gives the Sn(Ⅳ) complex, N[CH_2CH(CH_3)O]_3SiSnBr_3(CH_3OH)_2(3),$ which was characterized by various means.