CAREER: Tubularenes: A Novel Class of Conjugated Molecular Nanotubes

匹兹堡大学的劳伊·L·埃尔南德斯·S博士得到了美国国家科学基金会化学部高分子、超分子和纳米化学计划的支持，致力于设计、合成和表征由圆柱形共轭有机分子组成的纳米材料。这些分子形成了定义明确的线状纳米系统，直径约为1纳米，约为人类头发的10万倍。该项目的目标是对所涉及的化学有基本的了解，并使关键纳米部件的开发具有潜在的长期实际应用，例如在电子设备微型化和用于液体或气体分离的膜技术方面。从事该项目的学生将获得许多学科的技术技能，从大分子化学合成和产品表征到基础计算分析。此外，埃尔南德斯·S教授和他的学生通过匹兹堡科学与工程多样性联盟，积极参与激励少数族裔从事STEM职业，并通过座谈会、当地博览会和大会提高公众对科学的认识。埃尔南德斯·S教授还活跃在尤里卡街公司(Eureka Street Corporation)和墨西哥科学俱乐部(Clube de Ciencia México)，为来自墨西哥奇瓦瓦市的高中生和本科生举办STEM研讨会，致力于指导少数族裔的导师申请者。在这个项目中，埃尔南德斯·S教授和他的研究团队得到支持，开发合成协议来构建被称为管状分子的金属系统。该项目将遵循自下而上的模板辅助方法，使用精选的芳香族构建块和大环末端盖来构建共轭纳米管。选定的模板将理想地将前体芳香族构造物保持在接近的空间，以限制它们的自由度，并将它们定向在最能促进所需反应性的几何形状中。该项目的第一个目标是通过测试一系列芳香族积木和大循环来验证脚手架方法。第二个目标将集中在促进轴向共轭上。将评估中间体和预期产品的应变能，以便为径向和轴向延伸的共轭表面设计可行的合成路线。第三个目标是将杂原子作为掺杂剂加入到芳香族骨架中来调节电子结构。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，被认为是值得支持的。

Dr. Raúl Hernández Sánchez of the University of Pittsburgh is supported by the Macromolecular, Supramolecular, and Nanochemistry (MSN) Program of the Division of Chemistry at the NSF to design, synthesize, and characterize nanomaterials composed of cylindrical conjugated organic molecules. These molecules form well-defined wire-like nanosystems with diameters around one nanometer, which is about 100,000 times smaller than a human hair. The project goals are to gain fundamental understanding of the chemistry involved and to enable the development of critical nanocomponents, with potential long term practical applications, for example, in electronic device miniaturization and membrane technology for liquid or gas separations. Students working on the project will gain technical skills across many disciplines from macromolecular chemical synthesis and product characterization to basic computational analysis. In addition, Prof. Hernández Sánchez and his students are actively involved through the Alliance for Diversity in Science and Engineering at Pittsburgh in inspiring members of underrepresented minorities to pursue STEM careers and in increasing general public awareness of science through symposia, local fairs and conventions. Prof. Hernández Sánchez is also active as faculty in Eureka Street Corporation dedicated to mentor applicants from underrepresented minorities and in Clubes de Ciencia México (Science Clubs Mexico) to conduct STEM Workshops for high school and undergraduate students from Chihuahua City, México.In this project, Professor Hernández Sánchez and his research team are supported to develop synthetic protocols to construct molecular wire-like systems termed tubularenes. The project will follow bottom-up template-assisted approaches to build conjugated nanotubes using select aromatic building blocks and macrocycles end-caps. The selected templates would ideally hold the precursor aromatic building blocks close in space to limit their degrees of freedom and orient them in a geometry that best promotes the desired reactivity. The first aim of the project seeks to validate the scaffolding approach by testing a range of aromatic building blocks and macrocycles. The second aim will focus on the promotion of axial conjugation. Strain energies of intermediates and expected products will be assessed to inform the design of viable synthetic routes for radially and axially extended conjugated surfaces. The third aim involves the incorporation of heteroatoms into the aromatic framework as dopants to tune electronic structure. Computational chemistry will be used throughout to guide the project and allow for better informed design/modification/tuning decisions.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.