Concave Butterfly-Shaped Organometallic Hydrocarbons?
Matthew Laskoski
Department of Chemistry and Biochemistry The University of South Carolina Columbia, SC 29208 (USA) Fax (+1) 803-777-9521
Search for more papers by this authorGaby Roidl Dr.
Department of Chemistry and Biochemistry The University of South Carolina Columbia, SC 29208 (USA) Fax (+1) 803-777-9521
Search for more papers by this authorMark D. Smith Dr.
Department of Chemistry and Biochemistry The University of South Carolina Columbia, SC 29208 (USA) Fax (+1) 803-777-9521
Search for more papers by this authorUwe H. F. Bunz Prof. Dr.
Department of Chemistry and Biochemistry The University of South Carolina Columbia, SC 29208 (USA) Fax (+1) 803-777-9521
Search for more papers by this authorMatthew Laskoski
Department of Chemistry and Biochemistry The University of South Carolina Columbia, SC 29208 (USA) Fax (+1) 803-777-9521
Search for more papers by this authorGaby Roidl Dr.
Department of Chemistry and Biochemistry The University of South Carolina Columbia, SC 29208 (USA) Fax (+1) 803-777-9521
Search for more papers by this authorMark D. Smith Dr.
Department of Chemistry and Biochemistry The University of South Carolina Columbia, SC 29208 (USA) Fax (+1) 803-777-9521
Search for more papers by this authorUwe H. F. Bunz Prof. Dr.
Department of Chemistry and Biochemistry The University of South Carolina Columbia, SC 29208 (USA) Fax (+1) 803-777-9521
Search for more papers by this authorU.H.F.B. and M.L. thank the NSF for generous support (CAREER, CHE 9981765, 2000–2004). U.H.F.B. is Camille Dreyfus Teacher-Scholar (2000–2004).
Graphical Abstract
A metamorphosis of the tetraethynyl precursor 1 through double Cu-catalyzed ring closure leads to the corresponding butterfly-shaped cyclobutadiene complexes 2 in high yield (94 %). Single-crystal X-ray diffraction shows that the large organic ligand is distinctly nonplanar with a concave topology. Cp=cyclopentadiene.
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