Organocerium(IV) Chemistry

有机铈(IV)化学

• 批准号: 234604498
• 负责人: Professor Dr. Reiner Anwander
• 金额: --
• 依托单位: Institut für Anorganische Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/234604498?language=en
• 关键词: Organocerium; IV; Chemistry

Among the rare-earth elements cerium deserves special attention since it has access to the oxidation states +2, +3, and crucially +4. Because of their high oxidation potential, Ce(IV) compounds are routinely applied in organic synthesis, bioinorganic chemistry, materials science, and industrial catalysis (three-way catalytic converters, oxygen storage, etc.). Primary goal of this research project comprises the synthesis and full characterization of novel coordination compounds and organometallics of tetravalent cerium. Phenyliodine(III) dichloride is to be established as an innovative oxidant in rare-earth metal chemistry. Cerium(IV) amidinates and (silyl)amides as well as novel organocerium(IV) complexes bearing cyclopentadienyl and cyclooctatetraenyl ligands are relevant targets. In particular cases, the corresponding uranium(IV) amidinates will be synthesized to allow for the first time for a comparative study of a series of analogous cerium(IV) and uranium(IV) complexes with respect to their structure and reactivity. The reaction of metal chloride precursors with non-reducing alkylating agents such as ZnMe2 or SnMe4 might give access to the first organocerium(IV) complexes featuring sigma-bonded alkyl ligands. Furthermore, direct oxidation of cerium(III) alkyl derivatives will be systematically investigated as an alternative synthesis protocol. In order to prevent possible ligand oxidation, particular (ancillary) ligand sets will be employed. It can be foreseen that a moderate topical success already could have major implications for the development of organocerium(IV) chemistry. The research project also aims at the surface organometallic chemistry of the Ce(III)/Ce(IV) redox couple. The utilization of periodic mesoporous silicas as support material as well as the heterogenized silylamide route will be crucial criteria for studying the stability and reactivity of such molecular Ce(IV) surface species.

在稀土元素中，铈值得特别关注，因为它具有+2、+3和关键的+4氧化态。由于其高氧化电位，Ce（IV）化合物通常应用于有机合成、生物无机化学、材料科学和工业催化（三元催化转化器、储氧等）。 本研究计画的主要目标包括四价铈的新型配位化合物和有机金属化合物的合成和全面表征。二氯化苯基碘（III）将被确立为稀土金属化学中的创新氧化剂。铈（IV）脒基和（甲硅烷基）酰胺以及新的有机铈（IV）配合物轴承的cyclooctatetraenyl配体是相关的目标。在特定的情况下，相应的铀（IV）脒将被合成，允许第一次的一系列类似的铈（IV）和铀（IV）配合物的结构和反应性的比较研究。金属氯化物前体与非还原性烷基化剂如ZnMe 2或SnMe 4的反应可能会得到以σ键合的烷基配体为特征的第一有机铈（IV）络合物。此外，直接氧化铈（III）烷基衍生物将系统地研究作为一种替代的合成协议。为了防止可能的配体氧化，将采用特定的（辅助）配体组。可以预见，一个温和的局部成功已经可以有重大影响的发展有机铈（IV）化学。该研究项目还针对Ce（III）/Ce（IV）氧化还原对的表面有机金属化学。利用周期性介孔二氧化硅作为载体材料以及异质化的甲硅烷基酰胺路线将是研究这种分子Ce（IV）表面物种的稳定性和反应性的关键标准。