Low-valent Chromium - Molecules, Reactivity and Catalysis

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。 无机，生物无机和有机物化学计划支持特拉华州大学的克劳斯·西奥多博士在铬的低价有机金属化合物的反应化学方面的努力，特别强调选择性乙烯低聚的催化作用。 合成了各种环尺寸的顺磁性色环（含铬杂环，通过β-二酮亚胺（nacnac）配体连接）。 这些分子进行了研究，在其选择性方面消除与扩环。 由非无辜的二亚胺配体支撑的铬络合物也用于研究金属络合物与乙烯的反应性。 金属的电荷和形式氧化态影响乙烯低聚反应。该项目本质上是基础性的，但可能对商业催化剂的开发产生实际影响。 选择性催化工艺，如这里开发的那些，本质上是更可持续和环境友好的，因为它们避免了不需要的副产品的产生，并且更节能。 本科生和研究生体验不同的研究方法，并获得在合成和机械化学，这是在化学工业的高需求强大的背景。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The Inorganic, Bioinorganic, and Organometallic Chemistry Program supports the efforts of Dr. Klaus Theopold of the University of Delaware on the reaction chemistry of low-valent organometallic compounds of chromium, with particular emphasis on the catalysis of selective ethylene oligomerization. The paramagnetic chromacycles (heterocycles containing chromium ligated by beta-diketiminate (nacnac) ligands) of various ring sizes have been synthesized. These molecules are investigated in terms of their selectivity with respect to elimination versus ring expansion. Chromium complexes supported by non-innocent diimine ligands are also used for studies of metallacycle reactivity with ethylene. The charge and formal oxidation state of the metal impacts the ethylene oligomerization reaction. This project is fundamental in nature but may have practical impact on commercial catalyst development. Selective catalytic processes such as those developed here are inherently more sustainable and environmentally benign, as they avoid the production of undesirable byproducts and are more energy efficient. Undergraduate and graduate students experience varied research methodology and gain a strong background in synthetic and mechanistic chemistry, which is in high demand in the chemical industry.