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These elements (rare earths) perplex us in our researches, baffle us in our speculations and haunt us in our dreams. They stretch like an unknown sea before us - mocking, mystifying and murmuring strange revelations and possibilities. Sir William Crookes, Address to the British Association, 1887 The group will foccus on applications of lanthanide and actinide organometallic chemistry to organic synthesis, small molecule activation, and biological mimics. Lanthanide and early actinide chemistry has witnessed an ever increasing interest over the past two decades. Lanthanides have already found multiple uses in organic synthesis, materials, and biomedical applications. In contrast, the development of applications for early actinide and especially uranium chemistry has lagged behind and most of the studies are still of mainly academic importance. The increased study of f element chemistry reflects the belief that the unique properties of these elements will give rise to chemistry that differs from transition metal chemistry, thus extending applications beyond the d element frontier. Samarium diiodide (SmI2) has become one of the most widely used reducing agents in organic chemistry since the report of its facile synthesis in 1977. The chemistry of SmI2 has been thoroughly reviewed and it has been found that this compound can be successfully employed in a wide variety of transformations such as radical cyclizations, ketyl-olefin coupling, pinacolic coupling, Barbier-type reactions, aldol-type reactions, Reformatsky-type reactions , conjugate additions, and nucleophilic acyl substitutions. Shortly after the initial application of SmI2 to organic synthesis, it was observed that its reactivity and/or selectivity can be strongly influenced by the presence of various additives. One direction of research in the group will have as objective the development of well defined complexes to serve as models for the observed reactivity of SmI2 in the presence of additives. These studies should ultimately lead to the design of complexes that can be used in enantioselective/ catalytic applications besides adding to the understanding of low valent organolanthanide chemistry. The relative importance of the valence 5f orbitals in the bonding and electronic structure of actinide compounds continues to be the subject of considerable debate. To address such fundamental issues, the synthesis and investigation of a diverse range of organoactinides are necessary. In this respect, low valent, on one side, and high valent, on the other side, uranium complexes are targeted. Objectives such as uranium-nitride, uranium-phosphide, uranium-carbide, and uranium-uranium bonds have so far eluded synthetic chemists, but their feasibility has been supported by theoretical studies. Once generated, these and other types of unprecedented functionality will certainly exhibit new types of interesting and equally unprecedented reactivity.
Department of Chemistry & Biochemistry
Current members of Diaconescu Group
Former members of Diaconescu Group
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