CAS: Ultrafast Spectroscopy and Photoisomerization of Iron Sulfoxide Complexes

CAS：亚硫酸铁配合物的超快光谱和光异构化

• 批准号: 2247761
• 负责人: Jeffrey Rack
• 金额: $ 46.84万
• 依托单位: University of New Mexico
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2026-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2247761&HistoricalAwards=false
• 关键词: CAS; Ultrafast; Spectroscopy; Photoisomerization; Iron

With support from the Chemical Structure, Dynamics & Mechanisms-B (CSDM-B) Program of the Chemistry Division (CHE), and the Established Program to Stimulate Competitive Research (EPSCoR), Professor Jeffrey Rack of the University of New Mexico is developing new classes of iron complexes with interesting spectroscopic and magneto-optical properties. The goal of this research is to design new photoactive iron complexes with sulfoxide ligands. The project lies at the interface of organic, inorganic, and physical chemistry, and is appropriate for education of scientists at all levels of experience. The University of New Mexico is a majority minority institution and the Rack research group is works to provide the highest level of education and training for students underrepresented in science and will continue to do so under this award. Outreach activities involving the training of high school and middle chemistry teachers is part of the research project. The proposed work details a research plan to create photoactive iron polypyridine sulfoxide complexes. The goal of this work is to discover if phototriggered sulfoxide isomerization can be supported on iron centers in a fashion similar to that on related ruthenium complexes. In ruthenium complexes, 3MLCT excitation prompts transient Ru3+ formation, which induces excited state isomerization of the sulfoxide from S-bonded to O-bonded. Professor Rack and his research team aim to reproduce this photochemistry on iron with the objective of stabilizing high or intermediate spin states with the O-bonded coordination mode. There are two major challenges that must be met to observe this chemistry on iron: 3MCLT (metal-to-ligand charge-transfer) states on iron are rare due to the primogenic effect and sulfoxide isomerization on iron has not been reported. Preliminary results provide evidence that these challenges can be overcome and that the goal of achieving S- to O-sulfoxide bonding on iron can be achieved. If successful, the ability to achieve such intermediate to high spin state Fe-sulfoxide complexes would be a significant advance for the field as this would bring this chemistry into the realm of earth abundant transition metal space, and open up an important new avenue of exploration for organometallic chemists.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.

在化学系 (CHE) 化学结构、动力学和机理-B (CSDM-B) 计划和刺激竞争性研究既定计划 (EPSCoR) 的支持下，新墨西哥大学的 Jeffrey Rack 教授正在开发新的具有有趣的光谱和磁光特性的铁配合物类别。这项研究的目标是设计具有亚砜配体的新型光活性铁配合物。该项目位于有机化学、无机化学和物理化学的交叉领域，适合对各种经验水平的科学家进行教育。新墨西哥大学是一个少数族裔占多数的机构，Rack 研究小组致力于为科学领域代表性不足的学生提供最高水平的教育和培训，并将在该奖项下继续这样做。涉及高中和初中化学教师培训的外展活动是该研究项目的一部分。拟议的工作详细介绍了创建光活性铁聚吡啶亚砜络合物的研究计划。这项工作的目标是发现光触发亚砜异构化是否可以以类似于相关钌配合物的方式在铁中心上得到支持。在钌配合物中，3MLCT 激发会促进瞬时 Ru3+ 的形成，从而诱导亚砜从 S-键到 O-键的激发态异构化。 Rack 教授和他的研究团队旨在在铁上重现这种光化学，目的是通过 O 键配位模式稳定高或中自旋态。要观察铁上的这种化学反应，必须满足两个主要挑战：由于原生效应，铁上的 3MCLT（金属到配体电荷转移）态很少见，而且铁上的亚砜异构化尚未见报道。初步结果证明这些挑战是可以克服的，并且可以实现在铁上实现 S- 至 O-亚砜键合的目标。 如果成功，获得这种中高自旋态铁亚砜络合物的能力将是该领域的重大进步，因为这将使这种化学进入地球丰富的过渡金属空间领域，并开辟一条重要的新探索途径该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。