Structural analyses of 2-triorganylsilyl- and 2-triorganylstannyl聽derivatives of 5-alkyl-[1,3,5]-dithiazinanes. Do聽S鈰疭i and S鈰疭n interactions exist?

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• 作者：Ra煤l Colorado-Peralta ; Carlos Guadarrama-P茅rez ; Luis A. Mart铆nez-Chav ; o ; Juan Carlos G谩lvez-Ruiz ; Ang茅lica M. Duarte-Hern谩ndez ; Galdina V. Su谩rez-Moreno ; Aurora V谩squez-Badillo ; Sonia A. S谩nchez-Ruiz ; Rosalinda Contreras ; Angelina Flores-Parra
• 关键词：2-R3Si-[1 ; 3 ; 5]-dithiazinanes ; 2-R3Sn-[1 ; 3 ; 5]-dithiazinanes ; N-borane adducts ; S鈰疭i and S鈰疭n weak interactions ; Conformational analyses
• 刊名：Journal of Organometallic Chemistry
• 出版年：1 February, 2014
• 年：2014
• 卷：751
• 期：Complete
• 页码：579-590
• 全文大小：1557 K

文摘

A series of (E聽=聽Si or Sn; R鈥猜?聽Me or Ph) derivatives of 5-R-[1,3,5]-dithiazinanes (R聽=聽Me, iPr, tBu) are reported, as well as some of their N-BH₃ adducts. Structures were determined by ²⁹Si, ¹¹⁹Sn, ¹¹B, ¹³C and ¹H NMR and X ray diffraction analyses. Minimum energy conformations were calculated by HF/6-31++G(d,p) and B3LYP/6-31++G(d,p) methods. Preferred conformations and steric and stereoelectronic interactions are analyzed. In the solid state the ring conformation is a chair with the N-R group in axial and the 2-substituents in equatorial position. The Si or Sn atoms linked to C-2 have short distances to the two sulfur atoms, interpreted as Si鈰疭 and Sn鈰疭 stabilizing contacts. The ¹¹⁹Sn NMR chemical shifts and ¹J(¹³C,¹¹⁹Sn) coupling constants evidenced weak S鈰疭n coordination bonds. Substitution reactions at C2 performed in N-BH₃ adducts of 2-lithium-5-methyl-[1,3,5]-dithiazinanes of anchored conformation proceed with retention of C2 configuration.