在葡萄糖碳酸盐环开聚合过程中调节区域选择性的侧链功能
Yue Song, Xin Yang1, Yidan Shen
1Laboratory for Molecular Simulation, Texas A&M University, College Station, Texas 77842, United States.
Journal of the American Chemical Society
|September 23, 2020
概括
循环葡萄糖碳酸盐的侧链功能在有机催化环开放聚合过程中显著影响区域选择性. 邻近的组直接聚合,使得可控的聚甲酸 (PGC) 的合成.
科学领域:
- 聚合物化学
- 有机合成
- 催化剂
背景情况:
- 有机基催化对于聚合物合成至关重要.
- 循环d-葡萄糖碳酸盐是创建功能聚合物的多功能单体.
- 聚合中的区域选择性决定了聚合物的特性.
研究的目的:
- 研究侧链功能对1,5,7-triazabicyclo[5.4.0]dec-5-ene (TBD) 催化环开聚合 (ROP) 的区域化学结果的影响.
- 阐明六个组成的循环d-葡萄糖碳酸盐在ROP中控制区域选择性的分子机制.
- 为设计具有可控聚合物合成特定功能的单体提供洞察力.
主要方法:
- 使用1,5,7-triazabicyclo[5.4.0]dec-5-ene (TBD) 的有机催化环开放聚合.
- 具有不同侧链功能的多4-糖碳酸盐 (PGC) 的合成和表征.
- 核磁共振 (NMR) 光谱 (1D和2D) 用于结构分析.
- 密度功能理论 (DFT) 计算以调查过渡状态和分子间相互作用.
主要成果:
- 对于具有碳酸盐侧链的PGC,在2位和3位实现了高区域选择性.
- 在以太侧链替代剂的PGC中观察到区域不规则性.
- 核磁共振研究证实了骨干连接和环开放偏好.
- DFT计算显示过渡状态通过侧链和TBD之间的键稳定.
结论:
- 侧链功能在TBD催化循环葡萄糖碳酸的ROP过程中发挥着关键作用.
- 涉及侧链和有机催化剂的分子间结相互作用是实现区域控制的关键.
- 这项研究为设计基于葡萄糖的单体提供了基础,这些单体具有控制聚合物架构的相邻功能.
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