Metallacarbatrane, Hydride, Fluoride, and Metal-Metal Bonded Compounds of the Main Group Elements: Synthesis and Applications

在这个由化学部化学合成计划资助的项目中，哥伦比亚大学化学系的Gerard Parkin教授研究了富含地球的主族金属化合物的基础化学。这项研究对于开发这类化合物作为有机转化催化剂和构建新材料的用途是必要的。催化剂对于将化学原料转化为更有用的化合物至关重要，一个重要的目标是发现不含贵金属的新催化剂。镁和钙是被研究的两种富含地球的主要组金属。调查的重点是使用多齿配体来加强主要基团元素的明确定义的配位环境。本研究中使用的配体的具体实例包括(I)三齿三脚架配体，例如三(吡唑基)氢硼酸盐和三(2-硫代咪唑基)氢硼酸盐，以及(Ii)四齿三脚架配体，例如三(2-吡啶硫基)甲基，而目标化合物的实例包括那些具有末端烷基、氢化物和氟化物的配体，以及那些具有金属-金属键的配体。研究包括使用单晶X射线衍射和核磁共振光谱方法来确定合成分子的结构，以及计算方法来分析成键。这些活动的一个重要方面是，它涉及将学生培养成未来的专业人员，无论是在学术还是工业环境中。按照研究小组的惯例，研究活动不仅涉及研究生和本科生，还涉及高中生，从而为他们在教育的关键时刻提供重要的STEM经验。此外，该研究小组还参与了为纽约市不同种族公立中学的孩子们进行化学演示。

In this project funded by the Chemical Synthesis Program of the Chemistry Division, Professor Gerard Parkin of the Department of Chemistry at Columbia University investigates fundamental chemistry of compounds of Earth-abundant main group metals. This research is required for developing the use of such compounds as catalysts for organic transformations and for constructing new materials. Catalysts are critical for the conversion of chemical feedstocks into more useful compounds, and an important objective is to discover new catalysts that do not incorporate precious metals. Magnesium and calcium are two examples of Earth-abundant main group metals that are investigated. The investigation focuses on the use of multidentate ligands to enforce well-defined coordination environments for main group elements. Specific examples of ligands that are used in this research include (i) tridentate tripodal ligands, such as tris(pyrazolyl)hydroborato and tris(2-mercaptoimidazolyl)hydroborato, and (ii) tetradentate tripodal ligands, such as tris(2 pyridylthio)methyl, while examples of target compounds include those with terminal alkyl, hydride, and fluoride ligands, and also those which feature metal?metal bonds. The research involves the use of single crystal X-ray diffraction and NMR spectroscopic methods to determine the structures of the synthesized molecules, and computational methods to analyze the bonding. An important aspect of the activities is that it involves training students to be future professionals, be it in an academic or industrial setting. As is customary for the research group, the research activities not only involve graduate and undergraduate students, but also involve high school students, thereby providing a significant STEM experience for them at a critical point in their education. In addition, the research group is also involved in performing chemistry demonstrations for children from ethnically diverse New York City public middle schools.