Gold(I) Complexes Containing Unsaturated Hydrocarbyl Ligands

在化学系化学结构、动力学和机理B计划资助的这个项目中，Ross A.杜克大学化学系的Wesserhoefer将研究中性金（I）络合物的新化学。该项目的重点是不饱和烃基配体，包括σ-烯基，-烯丙基，-联烯基和-炔丙基配体。本研究的一个目标是发展这些配合物的结构和流动行为的有意义的理解，并同样通过这些配合物进行亲电脱氧（金的损失）的机制的理解。在这样做的过程中，这些活动将提供机制的见解，将服务于不断增长的全球研究人员社区，致力于（1）开发新的和更有效的金（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研究生和本科生研究人员的科学教育和培训，包括来自传统上在科学领域代表性不足的族裔群体的学生。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。研究生将与杜克核磁共振中心的Ben Bobay博士合作参加社区外展活动，旨在为当地高中生提供现代高场核磁共振光谱学的实践机会，并在核磁共振数据的处理，操作和解释方面提供一对一的指导。尽管在这一领域的研究越来越多，但关于结构的实验信息有限，含不饱和烃基配体的金络合物的反应性和流动行为，所述不饱和烃基配体包括σ-烯基、-烯丙基、-丙二烯基和-炔丙基配体。拟议的研究活动旨在填补这些空白，并开发一个实验接地的理解金络合物含有不饱和烃基配体。 重点是了解这些配合物的结构和流动行为，以及亲电脱氧的机理。这项研究将涉及两个调查领域。第一个领域涉及澄清的机制，包括直接攻击的C=C烯基键的金烯基络合物的亲电加成（i）验证亲电加成的π-α途径，（ii）验证亲电加成的π-β途径，和（iii）建模的过渡态/中间体的炔/烯烃环加成。第二个领域涉及具有β、γ和/或γ、δ不饱和度的金烃基络合物的结构、流动行为和亲核行为的阐明，特别针对（i）金σ-烯丙基络合物，（ii）金σ-联烯基和σ-炔丙基络合物，及（iii）金3-该奖项反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的知识支持优点和更广泛的影响审查标准。

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.