Methods for Regiocontrol in Polarized Polyene Systems

在化学系化学合成项目的支持下，伊利诺伊大学芝加哥分校(UIC)的贾斯汀·莫尔正在研究一种新技术，以控制一类被称为极化多烯的多功能且容易生成的中间体发生的化学转化的性质。正在探索的反应性类型是对现有有机合成方法的补充，预计将简化药剂、农用化学品和其他有用先进材料的制造。结合催化剂发现工作，这项研究将瞄准新的策略，以精确控制从极化聚烯获得的复杂产品的原子连接性和三维结构。至关重要的是，由于这些起始材料能够以各种不同的方式发生反应，这项研究有望在不同的化学途径管理领域取得重要的基础性进展。莫尔实验室内不同人口统计的本科生和研究生群体将进行这项资助的研究。这些人将获得宝贵的技术和科学技能，这些技能与未来在以科学、技术、工程和数学(STEM)为基础的劳动力队伍中的潜在职业相关。该项目的更广泛影响将包括由莫尔研究小组开展的外联活动，因为他们与芝加哥地区的K-12学生接触，以促进科学教育。此外，为了补充这些和其他正在进行的扩大参与的努力，莫尔博士积极招募属于代表性不足群体的本科生参与他在UIC的实验室的化学研究，UIC是一家为少数群体服务的机构(MSI)。通过对日益复杂的中间体的基本反应性获得新的见解，促进了多功能分子组装的有效策略的开发。正是从这一角度来看，资助的项目侧重于开发一套从共轭二烯醇体系[例如1-(tert-butyldimethylsilyloxy)-1，3-cyclohexadiene]，]进行的伽马选择性转化[例如，每一个例子都可能为拟定理想的目标类别提供一个有用的新的合成工具。这项研究的具体目标包括：(1)通过考察新颖的手性配体和手性辅助设计，开发铜和镍催化的立体选择性C-C键形成反应；(2)扩展金属催化的偶联技术，将有问题的伯卤化物偶联伙伴包括在内；(3)考察二烯醇醚的单电子氧化反应，生成具有区域选择性反应活性的新型自由基阳离子中间体；(4)探索过渡金属催化的、位置选择性的多烯体系中C-杂原子键的形成。最终，这项研究有望帮助建立对影响和控制多烯系统区域和立体选择性的基本因素的日益增长的理解。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With the support of the Chemical Synthesis program in the Division of Chemistry, Justin Mohr of the University of Illinois at Chicago (UIC) is studying new techniques to control the nature of chemical transformations occurring from a class of versatile and readily generated intermediates called 'polarized polyenes.' The type of reactivity being explored complements established methods for organic synthesis and it is anticipated to streamline the manufacture of pharmaceutical agents, agrochemicals, and other useful advanced materials. In conjunction with catalyst discovery efforts, this research will target new strategies to precisely control the atomic connectivity and three-dimensional structure of complex products obtained from polarized polyenes. Crucially, and because these starting materials are capable of reacting in a variety of different ways, the research promises important fundamental advances in the area of divergent chemical pathways management. A demographically diverse group of undergraduate and graduate students within the Mohr laboratory will conduct the funded research. These individuals will gain valuable technical and scientific skills of relevance to potential future careers in the science, technology, engineering, and mathematics (STEM)-based workforce. The broader impacts of the project will include outreach activities conducted by the Mohr research team as they engage with Chicago-area K-12 students to promote science education. In addition, and to complement these and other ongoing efforts to broaden participation, Dr. Mohr actively recruits undergraduate students belonging to underrepresented groups to become involved in chemical research in his laboratory at UIC, a minority-serving institution (MSI).The development of efficient strategies for the assembly of polyfunctional molecules is facilitated by gaining new insights into the fundamental reactivity of progressively more complex intermediates. It is from this standpoint that the funded project focuses on the development of a suite of gamma-selective transformations from conjugated dienol systems [e.g., 1-(tert-butyldimethylsilyloxy)-1,3-cyclohexadiene], each example of which may provide a useful new synthetic tool for the elaboration of desirable target classes. Specific aims of the research include: (1) development of copper- and nickel-catalyzed stereoselective C–C bond forming reactions through examination of novel chiral ligand and chiral auxiliary designs, (2) expansion of metal-catalyzed coupling techniques to include problematic primary halide coupling partners, (3) examination of single-electron oxidation of dienol ethers to generate novel radical cation intermediates exhibiting regioselective reactivity, and (4) exploration of transition metal-catalyzed, site-selective C–heteroatom bond formation in polyene systems. Ultimately, the research is expected to help build a growing understanding of the basic factors that influence and control regio- and stereo-selectivity in polyene systems.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.