Highly Reduced Complexes: C-C Bond Forming Reactions of Arenes Coordinated to Manganese (-I)

N. John Cooper博士，匹兹堡大学化学系，由化学系无机、生物无机和有机金属项目支持，研究高度还原的锰络合物。该项目的主要目标是利用四合物Mn（- 1）苯配合物的不寻常反应性来开发芳烃与过渡金属配合的新反应。阳离子试剂的亲电性，如六hapto Mn(I)配合物、铝盐和阳离子环庚三烯基配合物，将被用来驱动Mn(I)配合物的添加。这些添加物有望产生新的联芳基配体、氨基烷基取代配体和6:4:7融合环体系。对这些加成物的机制和范围的基础研究将使用烯酮进行探索，并将测试与钾镁盐的反应，以强制进入（2+2）加成物，从而导致4元碳环在苯核上的融合。从金属中心去除二烯配体的策略也将被研究。所提出的反应有几个共同的特征，这些特征可能使它们在有机合成中具有战略价值；所有这些都涉及到在苯核上形成新的C-C键，许多引入了有用的合成官能团，所有这些都可能是立体特异性的，并且大多数应该与芳烃核上的其他取代基可接近。苯是化学中最核心的分子之一，本研究的更广泛意义在于，它将引发苯的新反应，而这是传统有机方法无法实现的。这些研究将为苯的碳-碳键形成反应提供新的线索，预计结果将在有机合成领域具有普遍的实用价值。

Dr. N. John Cooper, Department of Chemistry, University of Pittsburgh, is supported by the Inorganic, Bioinorganic, and Organometallic Program of the Chemistry Division for studies of highly reduced complexes of manganese. The primary objective of this project is to use the unusual reactivity of a tetrahapto Mn(-I) benzene complex to develop new reactions of arenes coordinated to transition metals. The electrophilicity of cationic reagents, such as the hexahapto Mn(I) complex, iminium salts, and cationic cycloheptatrienyl complexes, will be used to drive additions to the Mn(-I) complex. These additions are expected to produce new biaryl ligands, amino alkyl substituted ligands, and 6:4:7 fused ring systems. Fundamental studies of the mechanism and the scope of these additions will be explored using ketenes, and reactions with keteniminium salts will be tested to force entry into (2+2) additions which lead to fusion of a 4-membered carbon ring on to the benzene nucleus. Strategies for the removal of the diene ligands from the metal center will also be investigated. The reactions proposed share several characeristics which are likely to make them of strategic value in organic synthesis; all involve formation of new C-C bonds to the benzene nucleus, many introduce useful functional groups for synthesis, all are likely to be stereospecific, and most should be accessible with other substituents on the arene nucleus. Benzene is one of the most central molecules in chemistry, and the broader significance of the proposed ressarch is that it will lead to new reactions of benzene which cannot be achieved through traditional organic methods. These studies will shed new light on carbon-carbon bond forming reactions to benzene, and the results are expected to be of general utility to the field of organic synthesis.