具有斜五角金字塔图案的热稳定型甲基烯:C60 (C2F5) 4O,C60 (CF3) 4O和C60 (CF3) 6
Ivan E Kareev1, Natalia B Shustova, Igor V Kuvychko
1Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432, Russia.
Journal of the American Chemical Society
|September 14, 2006
概括
新的富勒烯衍生物,包括C60) CF3)) 6) 和两个环氧化物,具有独特的结构和增强的热稳定性. 这些发现证明了斜-五角-金字塔 (SPP) 加法模式在高温下的动力稳定性.
科学领域:
- 材料科学 材料科学 材料科学
- 有机化学 有机化学
- 纳米技术纳米技术
背景情况:
- 富勒,特别是C 60),是具有独特电子和结构性质的碳基.
- 富勒与 perfluoroalkyl 组 (R(f)) 的功能化可以改变它们的特性和稳定性.
- 斜五角金字塔 (SPP) 添加模式是富勒烯化学中已知的图案.
研究的目的:
- 为了研究C(60) 与三二甲 (CF(3) I) 和五乙酸 (C(2) F(5) I) 的高温反应.
- 在这些条件下形成的新型烯衍生物,包括异构体和环氧化物,的特征.
- 评估这些新化合物的热稳定性和结构特征,特别是那些具有SPP添加模式的化合物.
主要方法:
- 在高温反应中,C ((60) 与CF ((3) I和C ((2) F ((5) I.
- 使用质谱学,DFT量子化学计算,拉曼可见光和19FNMR光谱学进行了表征.
- 单晶X射线衍射用于环氧衍生物的结构性确定.
主要成果:
- 一个C(60)(CF(3)) ((6) 异构体的合成,其中C(s) -C(60) X(6) 是SPP的加法模式.
- 两个环氧衍生物的形成,C(s) -C(60) -CF(3)) -4) O和C(s) -C(60) -C(2) F(5) -4) O,与SPP模式的变化.
- 该C ((s) -C ((60) ((CF ((3)) ((6)) 化合物表现出一种固态阻碍的C-C键 (1.60 Å) 和一种罕见的非快速交换的 (19) F NMR频谱.
- 环氧化物是第一种具有非外体替代物的多 (?? ) 基烯衍生物,在高温下稳定.
- 在超过400°C的温度下,SPP添加模式显示出动力稳定性.
结论:
- 烯衍生物中的SPP添加模式在高温 (>400°C) 时是稳定的.
- perfluoroalkyl 替代剂可以提高烯衍生物的热稳定性.
- 合成的化合物代表了新的富勒结构,在材料科学中具有潜在的应用.
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