SusChEM: Stereoselective Polymerization of Biomass Monomers by Transition-Metal and Organic Catalysts

化学催化计划支持教授尤金Y的努力。陈博士，科罗拉多州立大学，研究新型立体选择性聚合体系，通过手性过渡金属和有机催化剂，以催化方式从生物质衍生的丙烯酸单体合成高价值的有规立构和手性聚合物或光学拆分化学品。 本论文采用合成、催化、机理和计算等方法实现了三个具体目标：（1）通过手性过渡金属催化剂的分子工程实现生物质丙烯酸酯的立体选择性聚合;（2）通过手性离子对促进的穿梭聚合实现生物质丙烯酸酯的催化聚合和大体积丙烯酸酯的催化不对称聚合;（3）通过内、外链转移途径和手性有机催化剂的应用，发展丙烯酸酯的催化和不对称双聚反应。 多样化的实验技术与国际合作相结合，带来了互补的理论专业知识。 该项目福尔斯SusChEM倡议，因为它使用非石油基起始材料（例如，植物生物质）用于生产潜在的商品规模产品。 这项研究提供了教育机会，培训和教学的学生在催化和聚合物材料，对全球经济的核心领域的广泛技术。 学生还了解可持续发展，为他们提供了一个坚实的基础，以解决全球问题，并在他们未来的专业工作场所发挥领导作用。科罗拉多州立大学的Chen博士，对金属和有机催化的丙烯酸聚合进行了研究。 金属催化路线不同于传统的（阴离子或自由基）丙烯酸聚合有三种方式：（a）它是催化剂位点控制的，因此分子催化剂可以设计用于在室温下高精度合成各种聚合物;（B）它确保每个单体具有相同程度的手性诱导，以产生均匀的手性聚合物;和（c）催化循环可以通过用于催化生产有规立构或手性聚合物的内部或外部方法来构建。 有机催化路线表现出体现可持续/绿色化学的几个关键原则的特征：它仅使用少量相对无毒的有机催化剂，并在室温下反应不到1分钟内将所有单体快速转化为高分子量生物塑料。 从技术的观点来看，两种聚合系统都可以在经济上可行的条件下操作（例如，在较低温度下和以催化方式），并使用可再生原料生产技术上重要的有规立构或手性聚合物，这不仅提供了石油基聚合物的可持续替代品，而且还提供了上级材料性能。 陈教授正在为高年级本科生和研究生编写一本关于“可持续发展的化学”的新教材。这篇文章被设想用于教育化学和化学工程的学生，以及在化学在可持续发展中的核心作用的一般公众。

The Chemical Catalysis Program supports the efforts of Professor Eugene Y. Chen of Colorado State University in the investigation of new stereoselective polymerization systems by chiral transition-metal and organic catalysts for the synthesis of high-value stereoregular and chiral polymers or optically-resolved chemicals from biomass-derived acrylic monomers in a catalytic fashion. Synthetic, catalytic, mechanistic, and computational methods are employed to accomplish three specific objectives: (1) establishing stereoselective polymerization of biomass acrylics through molecular engineering of chiral transition-metal catalysts; (2) advancing hydride-shuttling polymerizations promoted by chiral ion pairs to enable catalytic polymerization of biomass acrylics and catalytic asymmetric polymerization of bulky acrylics; and (3) developing catalytic and asymmetric organopolymerizations of acrylics via internal and external chain transfer routes and utilization of chiral organic catalysts. Diverse experimental techniques are coupled with international collaborations that bring in complementary theoretical expertise. This project falls under the SusChEM initiative as it utilizes non-petroleum based starting materials (e.g., plant biomass) for the production of potential commodity-scale products. This research provides educational opportunities for training and teaching of students with a wide range of techniques in catalysis and polymeric materials, areas central to the global economy. Students also learn about sustainability, providing them with a strong basis to address global problems and play leadership roles in their future professional workplaces.The Chemical Catalysis Program supports the efforts of Eugene Y. Chen of Colorado State University for the investigation of metal-and organically-catalyzed polymerization of acrylics. The metal-catalyzed route departs from conventional (anionic or radical) acrylic polymerizations in three ways: (a) it is catalyst site-controlled so that molecular catalysts can be engineered for the synthesis of a wide range of polymers with high precision at room temperature; (b) it ensures the same degree of chiral induction for each monomer to produce uniform chiral polymers; and (c) catalytic cycles can be constructed by internal or external processes for catalytic production of stereoregular or chiral polymers. The organocatalysis route exhibits characteristics that embody several key principles of sustainable/green chemistry: it employs only a small amount of the relatively non-toxic organic catalyst and rapidly converts all monomers to high molecular weight bioplastics in less than 1 min of reaction at room temperature. From a technological point of view, both polymerization systems can be operated under economically viable conditions (e.g., at lower temperatures and in a catalytic fashion) and produce technologically important stereoregular or chiral polymers using renewable feedstocks, which offer not only sustainable alternatives to petroleum-based polymers, but also superior materials properties. Professor Chen is preparing a new textbook for senior undergraduate and graduate level students on the "Chemistry of Sustainability". This text is envisioned for use in educating chemistry and chemical engineering students as well as the general public in the central role of chemistry in sustainability.