Fundamental Chemistry of Carbenes and Diazirines

美国国家科学基金会化学部的有机和高分子化学项目支持罗伯特·A·他将通过快速和超快速光谱方法研究卡宾、二氮杂环丙烷和其他活性物质。这些研究旨在将分子结构与高活性、短寿命有机中间体的反应通道相关联。新的合成方法也将被开发用于卡宾的双吖丙啶前体。目标领域将包括测量卡宾-烯烃加成的活化参数以及这些加成中焓和熵的相互作用;卡宾溶剂化的光谱研究;以及嵌固卡宾的化学。二氟卡宾将从二氟二氮杂环丙烷生成，并将确定其加成到烯烃的绝对动力学。烯烃加成的活化参数将通过纳秒激光闪光光解（LFP）测量，用于苯基氯卡宾、二氯卡宾、氟氯卡宾、甲氧基氯卡宾、苯基氟卡宾、二氟卡宾、甲氧基氟卡宾、甲基甲氧基卡宾、苯基甲氧基卡宾和二甲氧基卡宾。Moss教授在上一个奖项期间的研究有助于培养5名本科生（2名女性，3名男性），3名研究生（2名女性和1名非洲裔美国人）和6名博士后学生（1名女性，5名男性）。除了对不同群体的学生进行培训外，莫斯教授还撰写了学术评论，允许扩大他的NSF赞助的研究，从而达到化学界更广泛的部分。在他最近的资助期间，他出版了两本广受欢迎的，共同编辑的关于活性中间体化学的书。此外，他还撰写了四篇评论，涉及单重态卡宾的化学;双吖丙啶的合成; SNi断裂反应;以及卡宾和双吖丙啶化学的新机制。学术评论的出版将继续进行，未来的主题包括卡宾的碎裂，卡宾-烯烃加成中焓和熵的相互作用，以及二卤代二氮杂环丙烷的合成。

The Organic and Macromolecular Chemistry Program in the Chemistry Division at the National Science Foundation supports Professor Robert A. Moss of Rutgers University who will study carbenes, diazirines, and other reactive species by fast and ultrafast spectroscopic methods. These studies are intended to correlate molecular structure with the reaction channels of highly reactive, short-lived organic intermediates. Novel syntheses will also be developed for diazirine precursors of carbenes. Target areas will include the measurement of activation parameters for carbene-alkene additions and the interplay of enthalpy and entropy in these additions; spectroscopic studies of carbene solvation; and the chemistry of incarcerated carbenes. Difluorocarbene will be generated from difluorodiazirine, and the absolute kinetics of its additions to alkenes will be determined. Activation parameters for alkene additions will be measured by nanosecond laser flash photolysis (LFP) for phenylchlorocarbene, dichlorocarbene, fluorochlorocarbene, methoxychlorocarbene, phenylfluorocarbene, difluorocarbene, methoxyfluorocarbene, methylmethoxycarbene, phenylmethoxycarbene, and dimethoxycarbene. A fundamental and synoptic picture of carbene-alkene addition reactions will be constructed and parallel computational studies will be conducted.Research by Professor Moss in the previous award period has contributed to the training of five undergraduates (2 females, 3 males), three graduate students (2 females and one African American), and six postdoctoral students (one female, 5 males). In addition to the training of a diverse group of students, Professor Moss has produced scholarly reviews that permit amplification of his NSF-sponsored research and thus reach a wider segment of the chemical community. During his most recent grant period, he published two well-received, co-edited books on the chemistry of reactive intermediates. In addition, he authored four reviews dealing with the chemistry of singlet carbenes; the synthesis of diazirines; SNi fragmentation reactions; and new mechanisms in carbene and diazirine chemistry. The publication of scholarly reviews will continue, with future topics to include the fragmentation of carbenes, the interplay of enthalpy and entropy in carbene-alkene additions, and the synthesis of dihalodiazirines.