稳定的螺旋型多胺:聚[N-(1-乙烯) -N'-[(R) -和/或 (S) -3,7-二甲基洛]胺]
Hong-Zhi Tang1, Yujie Lu, Gonglu Tian
1Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, USA.
Journal of the American Chemical Society
|March 25, 2004
概括
化催化剂从化单体中产生多化. 一些聚合物在高温下拉塞米化,而另一些聚合物则形成稳定的螺旋体,可以控制聚合物结构和稳定性.
科学领域:
- 聚合物化学 聚合物化学
- 不对称的催化剂.
- 立体化学是一种立体化学.
背景情况:
- 状催化剂对于合成立体正规聚合物至关重要.
- 碳二胺聚合提供了一条通往具有潜在应用的多胺的途径.
- 控制聚合物战术性和形状是定制材料性质的关键.
研究的目的:
- 为了研究使用奇拉BINOL-Ti催化剂的奇拉碳二胺单体的不对称聚合.
- 探索催化剂结构对聚合物区域规律性和立体化学的影响.
- 为了研究合成的多素的热稳定性和构造性行为.
主要方法:
- 使用 (R) 和/或 (S) -BINOL-Ti 性催化剂进行非对称的聚合.
- 合成N-(1-甲基) -N'-基碳二胺基.
- 火实验用于研究种族化动力学.
- 光谱分析 (NMR,UV-Vis) 和溶液中的形状研究.
主要成果:
- 使用BINOL-Ti催化剂获得可溶,非区域常规的多素 (Poly-R1,Poly-S1).
- 在回火 (70-80°C) 时,Poly-R1经历了缓慢的种族化,激活能量为~36 kcal/mol.
- 使用 (IV) 三氧化物合成了高度区域规律的多素 (Poly-R2,Poly-S2).
- 聚-R2和聚-S2在溶液中采用稳定的螺旋形状,独立于动力或热力学控制.
结论:
- 性催化剂的选择显著影响了多素的区域规律性和立体化学稳定性.
- 在非区域常规的多素中,种族化是一种热激活的过程.
- 高度区域规律的多素具有稳定的螺旋结构,表明有序材料的潜力.
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