NSF Young Investigator: Electron Transfer in Metallo- Porphyrins

宾夕法尼亚大学的Michael Therien教授是美国国家科学基金会无机、生物无机和有机金属化学项目青年研究员奖的获得者。他通过开发一种新的合成策略来制备取代卟啉，通过使用该方法获得各种基于卟啉的供体-受体分子，并通过使用这些分子来探索两个中心之间的电子耦合，从而开始了他的职业生涯。在目前的资助下，他将利用这些分子来评估空穴与电子隧穿的相对重要性，通过“弱”链接（如氢键）测量耦合，探测量子拍在超快电子转移中的重要性，以及开发烷烃氧化催化剂。电子从一个位置转移到另一个位置的反应是生物系统中发生的最有趣、最重要、同时又显然最简单的反应之一。在这样的系统中，电子转移可以发生在很长的距离上，然后中间介质起着重要的作用。通过设计电子转移可以通过特定键流动的分子，可以回答有关这些键施加控制的基本和一般问题。这种分子将在卟啉的基础上构建，卟啉是广泛发现的参与生物电子转移的分子。这些结果将阐明卟啉化学的细节，发展对电子转移的理论认识，并为工业上重要的反应提供合成催化剂。

Proposal: 9357130 PI: Therien Professor Michael Therien of the University of Pennsylvania is the recipient of this NSF young Investigator Award from the Inorganic, Bioinorganic, and Organometallic Chemistry Program. He has launched his career by developing a new synthetic strategy for preparing substituted porphyrins, by using the method to obtain a wide variety of donor-acceptor molecules based on porphyrins, and by using these molecules to explore the electronic coupling between the two centers. Under the present grant he will exploit these molecules in order to assess the relative importance of hole versus electron tunneling, to measure coupling through "weak" links such as hydrogen bonds, to probe the significance of quantum beats in ultrafast electron transfer, and to develop catalysts for alkane oxidation. %%% Reactions in which an electron transfers from one site to another are among the most intriguing, significant, and at the same time apparently simple that can occur in biological systems. In such systems electron transfer can take place over long distances, and then the intervening medium assumes an important role. By designing molecules in which electron transfer can be forced to flow through specified linkages, fundamental and general questions can be answered regarding the control that these linkages exert. Such molecules will be constructed on the basis of porphyrins, which are molecules that are widely found to participate in biological electron transfer. The results will illuminate the details of porphyrin chemistry, develop the theoretical understanding of electron transfer, and provide synthetic catalysts for industrially significant reactions.