Gold(I) Complexes Containing Unsaturated Hydrocarbyl Ligands

在这个由化学系化学结构、动力学和机制B计划资助的项目中，杜克大学化学系的Ross A.Wdenhoefer教授将研究中性金(I)络合物的新化学。该项目的重点是不饱和碳氢化合物配体，包括西格玛-烯基、-烯丙基、-烯丙基和-丙叉基。这项研究的目标之一是对这些络合物的结构和流动行为有意义的了解，以及对这些络合物经历亲电脱氢(金的损失)的机制的了解。通过这样做，这些活动将提供机械性的见解，将为不断增长的全球研究人员社区服务，这些研究人员致力于(1)开发新的、更有效的金(I)催化转化和(2)阐明金(I)催化转化的机制。拟议的研究活动完全纳入了对研究生和本科生研究人员的科学教育和培训，包括传统上在科学界代表性较低的族裔学生。鼓励研究生通过参加杜克大学研究生院提供的教育活动来增加他们的研究生研究和教育经验。研究生将与杜克大学核磁共振中心的Ben Bobay博士合作参与社区推广活动，旨在为当地高中生提供现代高场核磁共振波谱的实践接触，并在处理、操作和解释核磁共振数据方面提供一对一指导。尽管在这一领域的研究越来越多，但关于含有不饱和烃基配体的金配合物的结构、反应活性和流动行为的实验信息有限。拟议的研究活动旨在填补这些空白，并以实验为基础了解含有不饱和碳氢配体的金络合物。重点是了解这些络合物的结构和流动行为以及亲电脱氢的机理。这项研究将涉及两个领域的调查。第一个领域涉及通过(I)验证亲电加成的pi-α途径，(Ii)验证亲电加成的pi-β途径，以及(Iii)模拟炔烃/烯烃环加成的过渡态/中间体，来阐明亲电体加成金烯基络合物的机理，包括直接攻击C=C链烯基键。第二个领域涉及阐明具有贝塔、伽马和/或伽马、三角洲不饱和度的金烃基络合物的结构、流动行为和亲核行为，特别针对(I)金的sigma-allyl络合物，(Ii)金的sigma-allenyl和sigma-propargyl络合物，以及(Iii)金的3-丁烯基络合物。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。

In this project funded by the Chemical Structure, Dynamics and Mechanisms B Program of the Chemistry Division, Professor Ross A. Widenhoefer in the Department of Chemistry at Duke University will investigate new chemistry of neutral gold(I) complexes. The project focuses on unsaturated hydrocarbyl ligands including sigma-alkenyl, -allyl, -allenyl, and -propargyl ligands. One goal of this research is to develop a meaningful understanding of the structures and fluxional behavior of these complexes and, likewise an understanding of the mechanisms through which these complexes undergo electrophilic deauration (loss of gold). In doing so, these activities will provide mechanistic insight that will serve the ever growing global community of researchers working toward (1) the development of new and more efficient gold(I) catalyzed transformations and (2) elucidation of the mechanisms of gold(I)-catalyzed transformations. The proposed research activities are fully integrated into the scientific education and training of the graduate and undergraduate student researchers, including students from ethnic groups traditionally underrepresented in the sciences. Graduate students are encouraged to augment their graduate research and educational experience through participation in educational activities offered through the Duke University Graduate School. Graduate students will participate in community outreach activities in collaboration with Dr. Ben Bobay of the Duke NMR center, directed toward providing local high school students with hands-on exposure to modern high-field NMR spectroscopy and one-on-one instruction in the processing, manipulation, and interpretation of NMR data.Despite a growing body of research in this area, limited experimental information is available regarding the structure, reactivity, and fluxional behavior of gold complexes containing unsaturated hydrocarbyl ligands including sigma-alkenyl, -allyl, -allenyl, and -propargyl ligands. The proposed research activities aim to fill these gaps and develop an experimentally-grounded understanding of gold complexes containing unsaturated hydrocarbyl ligands. Focus is on understanding the structure and fluxional behavior of these complexes and the mechanisms of electrophilic deauration. The research will address two areas of inquiry. The first area involves the elucidation of the mechanisms for the addition of electrophiles to gold alkenyl complexes involving direct attack on the C=C alkenyl bond by (i) validating the pi-alpha pathway for electrophilic addition, (ii) validating the pi-beta pathway for electrophilic addition, and (iii) modeling the transition state/intermediate for alkyne/alkene cycloaddition. The second area involves the elucidation of the structures, fluxional behavior and nucleophilic behavior of gold hydrocarbyl complexes possessing beta, gamma and or gamma, delta unsaturation, specifically targeting (i) gold sigma-allyl complexes, (ii) gold sigma-allenyl and sigma-propargyl complexes, and (iii) gold 3-butenyl complexes.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.