Unsaturated, Multifunctional Transition Metal Complexes

这个无机、生物无机和有机金属化学项目的奖项为印第安纳大学化学系的Kenneth G. Caulton博士在不饱和有机金属化合物的合成和反应研究方面提供了持续的支持。理论工作将与法国蒙彼利埃大学的Odile Eisenstein博士合作进行。这项研究的目的是确定几个不同的功能配体连接在同一个金属原子上的化合物的反应模式。所合成的化合物将含有诸如氢化物、卤化物、烷基和碳烯等配体的混合物。直接测定各种配体的相对反应活性，监测同一分子中烷基迁移、分子内还原消除等复杂反应。多功能金属配合物也可以将一个以上的官能团传递给另一个分子。选择目标化合物是因为它们在低温下进行亲核反应或氧化反应的能力。在这些条件下研究反应活性提高了鉴定初级反应产物的可能性，并最大限度地提高了反应的选择性。热力学参数将被确定。要研究的具体反应包括从锇羰基中还原消除苯，从16电子物种中去除卤化物以形成14电子化合物，以及三氟甲基配体形成二氟甲基配体的反应。广泛的有机金属化合物的异常反应将被研究，包括C-H和C-F键的激活和配位不饱和化合物的反应性。这类反应对于基本了解均相催化剂的行为是很重要的。

This award in the Inorganic, Bioinorganic, and Organometallic Chemistry Program provides continued support to Dr. Kenneth G. Caulton of the Chemistry Department, Indiana University, for synthesis and reaction studies of unsaturated organometallic compounds. Theoretical work will be carried out in collaboration with Dr. Odile Eisenstein of the Universite de Montpellier, France. The goal of the research is to determine reactivity patterns for compounds having several different functional ligands attached to the same metal atom. The compounds synthesized will contain a mixture of ligands such as hydride, halide, alkyl, and carbene. Relative reactivity of various ligands will be determined directly and complex reactions such as alkyl migration and intramolecular reduction elimination in the same molecule will be monitored. Multifunctional metal complexes may also deliver more than one functional group to another molecule. The target compounds will be selected because of their ability to undergo nucleophilic or oxidation reactions at low temperature. Studying reactivity under these conditions improves the possibility of identifying primary reaction products and maximizes the selectivity of reactions. Thermodynamic parameters will be determined. Specific reactions to be investigated include reductive elimination of benzene from osmium carbonyls, removal of halide from 16-electron species to form 14-electron compounds, and reaction of trifluoromethyl ligands to form difluoromethyl ligands. Unusual reactions of a wide range of organometallic compounds will be studied, including C-H and C-F bond activation and reactivity of coordinatively unsaturated compounds. Reactions of this kind are important to obtaining a basic understanding the behavior of homogeneous catalysts.