Studies of Olefin Triplets and Triplet Biradicals

这个更新奖是在有机动力学计划中获得的，以支持理查德·考德威尔博士的研究。烯烃三联体和三联体双基将被研究(1)通过传统的有机机理方法来确定化学结果和推断中间体的性质；(2)通过激光闪光光解测定瞬态寿命和系统间交叉速率，以及瞬态能量和动力学性质；(3)用CAS-MCSCF计算小模型系统的自旋轨道耦合。这些结果将导致对三重双基和烯烃三重基的基本理解，特别是它们的能量学和能量表面、构象、动力学，以及所有这些在决定光化学过程结果中的最终作用。研究的三联体反应包括开环重排、烯烃加成反应和烯烃三联体的系间交叉反应。了解双自由基中间体的基本性质和机理行为将为化学家设计新的烯烃三联体化学反应提供工具，并扩展其在合成光化学中的作用。

This renewal award is made in the Organic Dynamics Program in support of the research of Dr. Richard Caldwell. Alkene triplets and triplet biradicals will be studied (1) by conventional organic mechanistic methods to determine chemical outcomes and infer the nature of the intermediates; (2) by laser flash photolysis to determine transient lifetimes and intersystem crossing rates, and energies and kinetic properties of transients, and; (3) by CAS-MCSCF computations of spin-orbit coupling in small model systems. The results will lead to a fundamental understanding of triplet biradicals and olefin triplets, specifically their energetics and energy surfaces, conformations, dynamics, and ultimately the role of all of these in determining the outcomes of photochemical processes. Among the triplet reactions which will be studied are ring-opening rearrangements, olefin addition reactions, and intersystem crossing of olefin triplets. Understanding the fundamental properties and mechanistic behavior of biradical intermediates will provide the chemist with the tools to design new chemical reactions of alkene triplets and extend their role in synthetic photochemistry.