AEI 87 |
| The mechanical bonds and noncovalent forces contained within mechanically interlocked molecules give rise to relative motions, such as circumrotation and shuttling, that have been utilized in artificial molecular muscles and molecular electronic devices. Mechanically interlocked molecular compounds based on donor-acceptor interactions, incorporating cyclobis(paraquat-p-phenylene) (CBPQT4+) as the pi-electron accepting ring component, have been synthesized traditionally by template-directed, kinetically controlled reactions in which the partially formed ring is “clipped” around a dumbbell or macrocycle which contains complementary recognition units. Although this clipping approach has been used extensively, the moderate yields associated with the protocol limit its practical utility mostly to the preparation of [2]rotaxanes and [2]catenanes. We have recently harnessed the mild conditions, excellent functional group tolerance, and high efficiency of the Cu(I)-catalyzed Huisgen 1,3-dipolar cycloaddition for the preparation of a variety of previously inaccessible donor-acceptor rotaxanes and catenanes. The scope of this methodology is far-reaching, and examples of higher order rotaxanes, catenanes, polyrotaxanes, bistable [2]rotaxanes, and liquid crystalline materials will be presented.
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Academic Employment Initiative
8:00 PM-10:00 PM, Monday, August 20, 2007 BCEC -- Exhibit Hall - B2, Sci-Mix
Academic Employment Initiative |
