Reversible Complexation of Ethylene by a Silylene under Ambient Conditions

详细信息    查看全文

• 作者：Felicitas Lips ; James C. Fettinger ; Akseli Mansikkam?ki ; Heikki M. Tuononen ; Philip P. Power
• 刊名：Journal of the American Chemical Society
• 出版年：2014
• 出版时间：January 15, 2014
• 年：2014
• 卷：136
• 期：2
• 页码：634-637
• 全文大小：240K
• ISSN：1520-5126

文摘

Treatment of toluene solutions of the silylenes Si(SAr^Me₆)₂ (Ar^Me₆ = C₆H₃-2,6(C₆H₂-2,4,6-Me₃)₂, 1) or Si(SAr^Pri₄)₂ (Ar^Pri₄ = C₆H₃-2,6(C₆H₃-2,6-Prⁱ₂)₂, 2) with excess ethylene gas affords the siliranes (Ar^Me₆S)₂SiCH₂CH₂ (3) or (Ar^Pri₄S)₂SiCH₂CH₂ (4). Silirane 4 evolves ethylene spontaneously at room temperature in toluene solution. A Van鈥檛 Hoff analysis by variable-temperature ¹H NMR spectroscopy showed that 螖G_assn = 鈭?4.9(2.5) kJ mol^鈥? for 4. A computational study of the reaction mechanism using a model silylene Si(SPh)₂ (Ph = C₆H₅) was in harmony with the Van鈥檛 Hoff analysis, yielding 螖G_assn = 鈭?4 kJ mol^鈥? and an activation energy 螖G = 54 kJ mol^鈥?.