INOR 13 |
| Children never cease to be fascinated by toy gyroscopes, which commonly consist of (1) a rotating axis and disk, and (2) two to four static spokes that connect the termini of the axis. This talk will describe the syntheses of the first molecules that duplicate the connectivity, symmetry (Dnh), and rotational ability of such gyroscopes. Complexes with trans R3P-MLn-PR3 linkages are first prepared, with R groups that terminate with a CH=CH2 moiety. Then alkene metathesis is used to conduct a three-spoked cage molecule. The C=C units are hydrogenated to give gyroscope-like species. Yields are highest with rotators such as Fe(CO)3, which feature a three-fold symmetry axis, analogous to the phosphine ligands. However, reasonable yields can also be obtained with MLn = PtCl2, Rh(CO)Cl (square-planar geometry) and Re(CO)3X (octahedral geometry) Rotational barriers and substitution reactions of the MLn moieties will be described, as well as demetallations that yield dibridgehead diphosphines. Collaborative experiments directed at effecting unidirectional rotation will also be reported.
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Frontiers in Organometallic Chemistry
8:25 AM-12:00 PM, Sunday, August 19, 2007 BCEC -- 206 A/B, Oral
Division of Inorganic Chemistry |
