| Abstract
| - We have designed, synthesized, and investigated a self-assembling supramolecular system whichmimics, at a molecular level, the function performed by a macroscopic electrical extension cable. The systemis made up of three components, 12+, 2-H3+, and 3. Component 12+ consists of two moieties: a [Ru(bpy)3]2+unit, which plays the role of an electron donor under light excitation, and a DB24C8 crown ether, whichfulfills the function of a socket. The wire-type component 2-H3+ is also composed of two moieties, asecondary dialkylammonium-ion center and a bipyridinium unit, which thread into the DB24C8 crown-ether socket of 12+ and the 1/5DN38C10 crown-ether socket 3, respectively. The photochemical,photophysical, and electrochemical properties of the three separated components, of the 12+ ⊃ 2-H3+ and2-H3+ ⊂ 3 dyads, and of the 12+ ⊃ 2-H3+ ⊂ 3 triad have been investigated in CH2Cl2 solution containing2% MeCN. Reversible connection/disconnection of the two plug/socket systems can be controlledindependently by acid/base and redox stimulation. The behavior of the various different dyads and triadhas been monitored by light absorption and emission spectroscopies, as well as by electrochemicaltechniques. In the fully connected 12+ ⊃ 2-H3+ ⊂ 3 triad, light excitation of the [Ru(bpy)3]2+ unit of component12+ is followed by electron transfer (k = 2.8 × 108 s-1) to the bipyridinium unit of component 2-H3+, whichis plugged into component 3. Possible schemes to obtain improved molecular-level electrical extensioncables are discussed.
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