CHED 1261 |
| One of our research goals involves the design of new bridged cyclopentadienyl ligands for ansa-metallocene and metal fulvene complex chemistry using 1,3,6-trisubstituted fulvenes. The synthesis of the sterically demanding 1,3-diphenyl-6(R) (R = But, Ph, 1-naphthyl, 2-naphthyl, m-(C6H4)(OMe)) trisubstituted fulvenes has been carried out using 1,3-diphenylcyclopentadiene as starting material. Reductive coupling of the fulvene (R = But) using sodium naphthalenide gave the bridged dicyclopentadiene, rac-(C5H3Ph2)2(CHBut)2 1. The ligand precursor, rac-[(C5H2Ph2)2(CHBut)2]-2 2, was obtained by reaction of 1 with K[N(SiMe3)2] in THF, analogous to the chemistry we reported for rac-[(C5H2But2)2(CHBut)2]-2 3. Reaction of 2 or 3 with YbI2 in refluxing THF gave the new C2-symmetric ansa-ytterbocene(II) complexes, rac-[(C5H2Ph2)2(CHBut)2]Yb(THF) 4 and rac-[(C5H2But2)2(CHBut)2]Yb(THF) 5. The spectroscopic and single crystal X-ray results for the synthesis of the 1,3-diphenyl-6(R) fulvenes will be discussed in addition to the structure and reactivity of the ansa-ytterbocene(II) complexes. |
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Undergraduate Research Poster Session: Inorganic Chemistry
2:00 PM-4:00 PM, Monday, March 26, 2007 Hyatt Regency Chicago -- Riverside Center, Poster
Division of Chemical Education |