重新思考过渡金属催化N-碳素化物聚合:Pro和AcOProN-碳素化物的聚合
Rachel E Detwiler1, Austin E Schlirf1, Jessica R Kramer1
1Department of Biomedical Engineering, University of Utah, Salt Lake City, Utah 84112, United States.
Journal of the American Chemical Society
|July 20, 2021
概括
研究人员开发了使用N-carboxyanhydrides (NCAs) 合成聚蛋白 (PP) 的快速方法. 一个新的启动器使得可控聚合成为可能,克服了先前创建基于PP的先进生物材料的限制.
科学领域:
- 聚合物化学
- 生物材料科学
- 有机合成
背景情况:
- 基于聚烯 (PP) 的聚类对于蛋白质模仿剂和水凝等应用非常有价值.
- 现有的合成明确的高分子量PP材料的方法往往缓慢且低效.
- 传统的N-carboxyanhydride (NCA) 聚合通常需要一个胺NH质子来启动,这对以proline为基础的单体构成了挑战.
研究的目的:
- 开发易于使用,高产的方法来制备和聚合proline和trans-4-acetoxy-proline N-carboxyanhydrides (NCAs).
- 克服过渡金属催化NCA聚合物对基单体的局限性.
- 为了使可调节的,终端功能化的基于PP的同型,统计和块聚的合成.
主要方法:
- 开发了NCA单体的改进合成路径.
- 采用启动器绕过NH质子的需求,使得ProNCAs的受控活体聚合成为可能.
- 作为Pro NCA聚合物的替代催化剂进行了研究.
- 通过循环二极化 (CD) 光谱来表征多形状.
主要成果:
- 实现了Pro和trans-4-acetoxy-ProNCAs的轻松和高产制剂.
- 使用新型启动器证明了ProNCAs的高效,受控和活体聚合.
- 展示了合成可调节,终端功能PP基的同类,统计和阻断聚的能力.
- 在PP和trans-4-hydroxy-PP中确认了PPI和PPII螺旋体之间的形状转换.
结论:
- 这项研究在过渡金属催化NCA聚合中取得了突破,揭示了替代的传播机制.
- 开发的方法可以快速有效地获得明确的聚烯基材料.
- 这项工作为具有可调节性质的先进生物材料的合成开辟了新的途径.
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