一种含有-三键的稳定化合物.
Akira Sekiguchi1, Rei Kinjo, Masaaki Ichinohe
1Department of Chemistry, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan. sekiguch@staff.chem.tsukuba.ac.jp
Science (New York, N.Y.)
|September 18, 2004
概括
研究人员合成了一种稳定的-三键化合物,即1,1,4,4-四基[bis(trimethylsilyl) methyl]-1,4-二异-2-四烯. 这种独特的分子具有横曲结构和显著的热稳定性.
科学领域:
- 有机化学 有机化学
- 无机合成 无机合成
- 材料科学是一种材料科学.
背景情况:
- 合成具有原子之间多重键的化合物是具有挑战性的.
- 之前的研究已经探索了-双键,但三键仍然在很大程度上是难以捉摸的.
- 了解-多重键的电子和结构性质对于推进化学至关重要.
研究的目的:
- 为了合成和描述含有-三键的稳定化合物.
- 为了研究这种新型-三重键的结构和粘合特性.
- 为了比较-三重键的特性与碳-碳三重键 (alkynes) 的特性.
主要方法:
- 2,2,3,3-tetrabromo-1,1,4,4-tetrakis[bis(trimethylsilyl) methyl]-1,4-diisopropyltetrasilane与石墨 (KC8) 在四水中发生的反应.
- 隔离和净化所得到的产品.
- 进行X射线晶体学以确定分子结构和键长度.
- 热稳定性的分析.
主要成果:
- 成功合成了1,1,4,4-tetrakis[bis(trimethylsilyl) methyl]-1,4-diisopropyl-2-tetrasilyne,这是一个具有-三重键的稳定化合物.
- 该化合物形成绿色的晶体,在没有空气的情况下,在高达100°C的温度下保持稳定.
- -三重键的长度被确定为2.0622 ((9) 斯特.
- 在-三重键周围的替代物排列在一个跨形状,结合角度为137.44(4) 度.
结论:
- 一个稳定的-三重键首次被合成和特征化.
- -三重键表现出独特的结构特征,包括横曲几何形状,与线性酸盐不同.
- 在-三重键中观察到的键缩短大约是基与基相比,基中观察到的约一半,这表明了不同的结合特性.
相关概念视频
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