相关实验视频
Updated: Jul 28, 2026

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Hierarchical and Programmable One-Pot Oligosaccharide Synthesis
Published on: September 6, 2019
通过螺旋感选择性聚合合成的切尔机切换聚氨酸,使用[(R) -3,3'-二-2,2'-二纳夫托克西](二-特特-布托克西) ((IV) 催化剂
Hong-Zhi Tang1, Paul D Boyle, Bruce M Novak
1Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, USA.
Journal of the American Chemical Society
|February 17, 2005
概括
化复合物R-3诱导螺旋感选择性聚合. 由此产生的聚合物,聚-1b,表现出可逆的手术切换,没有固有的手术单元,这是一个新奇的现象.
科学领域:
- 有机金属化学 有机金属化学
- 聚合物科学 聚合物科学
- 超分子化学 超分子化学
背景情况:
- 状催化剂对于立体选择性合成至关重要.
- 具有受控结构的螺旋型聚合物具有显著的兴趣.
- 聚合物中的手术切换是一个正在发展的领域.
研究的目的:
- 为了合成新型的酸氧化复合物.
- 为了研究螺旋感选择性聚合的Achiral碳化物.
- 探索由此产生的螺旋聚合物的手术特性和切换行为.
主要方法:
- 合成和表征性复合物.
- 螺旋感选择性聚合利用一种性催化剂.
- 聚合物结构,立体规律性和分散性的分析.
- 研究手术特征 (棉花效应) 和取决于温度的切换行为.
主要成果:
- 合成和表征了一种性复合物,即 (R) -3,3'-二 -2,2'-二甲) (R-3) (IV) (R-3).
- R-3有效催化了N-(1-anthryl) -N'-octadecylcarbodiimide的螺旋感选择性聚合,产生了一个明确的螺旋聚合物 (聚-1b).
- 聚-1b在+38.5°C时显示可逆的手术切换和依赖于溶剂的棉花效应,尽管其骨干中缺乏手术部分.
结论:
- 化复合物可以有效地控制聚合物螺旋性.
- 合成的螺旋聚合物表现出前所未有的可逆性手术切换.
- 这种转换归因于悬挂类甲基的重定向,为响应性材料提供了新的可能性.
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Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
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