Metal-Arylisocyanide Chromophores for Photoredox Chemistry and Imaging

在这个由NSF化学部化学结构、动力学和机制B计划资助的项目中，Harry B教授。作者声明：Jay R.加州理工学院（Caltech）化学和化学工程系的Winkler正在开发一类具有特殊性能的发光过渡金属络合物，用于有机合成和生物成像。 有机合成和生物成像在开发疾病治疗方法方面都很重要。 一个强大的STEM推广计划，太阳能活动实验室，是在NSF的支持下开发的。 在此期间，Gray教授和Winkler教授，他们的博士后学者，研究生和本科生将继续参与这项工作，以翻译和转移加州理工学院的研究精髓，以提高公众对基础科学和工程原理的认识和理解。初步研究表明，均配钨芳基异氰配合物显示出显着的光谱和物理性质。这些分子具有高的单光子吸收消光系数（10的5次方），发光量子效率高达25%，激发态寿命长于1微秒。特别值得注意的是它们在811 nm处的双光子吸收截面，这是生物成像中非常重要的特性。这些横截面比许多商业双光子染料大10 - 100倍。设计了几组新的过渡金属芳基异氰酸酯，以增强这类发光分子的光谱和光物理性质。基于萘、菲、联苯和苯并菲环体系，制备了四种稠环芳异氰配体。新的芳基异氰配体将与第6、7和8族的过渡金属配位。只要可行，将通过X射线晶体学对新分子进行结构表征。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

In this project, funded by the Chemical Structure, Dynamics and Mechanisms B Program of the NSF Chemistry Division, Professors Harry B. Gray and Jay R. Winkler of the Division of Chemistry and Chemical Engineering at the California Institute of Technology (Caltech) are developing a class of luminescent transition metal complexes with exceptional properties for applications in organic synthesis and biological imaging. Both organic synthesis and biological imaging are important in developing cures for diseases. A strong STEM outreach program, the solar energy activity labs, was developed under prior NSF support. In this grant period, Professors Gray and Winkler, their postdoctoral scholars, graduate students, and undergraduates will continue their participation in this effort to translate and transfer the essence of Caltech research for the purpose of increasing public awareness and understanding of basic science and engineering principles.Preliminary research has revealed that homoleptic tungsten arylisocyanide complexes display remarkable spectroscopic and photophysical properties. These molecules have high 1-photon absorption extinction coefficients (ten to the power of 5), luminesce with quantum efficiencies as high as 25%, and have excited-state lifetimes longer than 1 microsecond. Of particular note are their two-photon absorption cross sections at 811 nm, a property of great importance in biological imaging. These cross sections are 10-100 times greater than many commercial 2-photon dyes. Several new groups of transition metal arylisocyanides are designed to enhance the spectroscopic and photophysical properties of this class of luminescent molecules. Four types of fused-ring arylisocyanide ligands will be prepared based on naphthyl-, phenanthryl-, biphenylene and triphenylene ring systems. The new arylisocyanide ligands will be coordinated to transition metals from groups 6, 7 and 8. New molecules will be structurally characterized by X-ray crystallography whenever feasible. The 1- and 2-photon absorption properties of the molecules will be evaluated and the excited-state lifetimes and quantum yields of all luminescent molecules will be determined.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.