循环氧化物和二氧化碳与二度复合物的不对称交替共聚化
Koji Nakano1, Kyoko Nozaki, Tamejiro Hiyama
1Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Journal of the American Chemical Society
|May 2, 2003
概括
模态复合物催化了氧化环素和CO2的共聚合. 在这种聚合过程中,复合体结构的修改增强了催化活性和酶选择性.
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
- 催化剂是一种催化剂.
背景情况:
- 环氧化物和二氧化碳的不对称交替共聚化对于合成功能性聚碳酸盐至关重要.
- 复合物被广泛研究为在聚合反应中利用二氧化碳的催化剂.
- 了解催化剂结构在控制活动和选择性方面的作用至关重要.
研究的目的:
- 为了合成和表征用于非对称交替共聚的新型二维复合物.
- 研究这些复合物的催化性能,在氧化环素和CO2的共聚合过程中.
- 阐明催化剂结构,活性和酶选择性之间的关系.
主要方法:
- 通过二甲与奇拉性pyrrolidinylmethanol联体的反应合成二度性复合物.
- 使用X射线晶体学进行结构性表征.
- 用MALDI-TOF质谱测量分析产品的非对称交替共聚化中的催化评估.
主要成果:
- 一种新的二次复合物 (2a) 被合成和特征化,具有一个Zn2O2四个成员的环.
- 复合物2a有效催化了氧化环素和二氧化碳的共聚合,产生了具有性联体作为启动组的共聚合物.
- 一个经过修改的复合物 (3a-OEt) 呈现出更高的催化活性和酶选择性,具有以基组作为发起物种.
结论:
- 在这种共聚合反应中,二元性物种是活性催化实体.
- 复合物的结构,包括连接体上的替代物,显著影响了催化性能.
- 这项研究表明了开发高效的二氧化碳利用和聚合物合成的性催化剂的途径.
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