The increase in host design complexity will come from the synthesis of rotaxane
and catenane host molecules that contain unique three dimensional cavities.
In 1991, he developed a rotaxane
by threading a molecular ring onto a thin molecule axle.
Stoddart, of Northwestern University in Evanston, 111., showed how to produce large quantities of molecular machines, starting with rings clipped around a central axle, a structure known as a rotaxane
. He and colleagues later devised molecular elevators and pumps.
In 1991, Stoddart, who is affiliated with Northwestern University, realized he could use an electron-poor open ring and electron-rich rod to create a rotaxane
or a ring on an axle.
Beer, "Anion-induced shuttling of a naphthalimide triazolium rotaxane
," Chemistry European Journal, vol.
In the paper, the group describes a simple rotaxane
in which the functional groups on the end have been modified into carboxylate groups.
Chapters address lab-scale and larger-scale synthesis of azide compounds; azides by olefin hydroazidation reactions; the chemistry of vinyl, allenyl, and ethynyl azides; small rings by azide chemistry; Schmidt rearrangement reactions with alkyl azides; radical chemistry with azides; cycloaddition reactions with azides; dipolar cycloaddition reactions in peptide chemistry; the azide/nitrene interface and the photochemistry of azides; organoazides and transition metals; azide-containing high energy materials; azide chemistry in rotaxane
and catenane synthesis, aza-Wittig reaction in natural product synthesis; and azides in carbohydrate chemistry.
In the same forum, Seung Soon Jang of the Georgia (USA) Institute of Technology discussed his work in computational nanotechnology in his presentation, "An Expedition To Find Treasures in the Field of Nanotechnology." He talked about his recent studies on nanoscale molecular electronics, particularly the rotaxane
molecule, which has exhibited an electromechanical switching behavior.
One possible answer to the many challenges ahead is the design and construction of a controllable rotaxane-like system aptly called a "molecular shuttle." A rotaxane
is composed of irreversibly interlocked molecules in the shape of a ring threaded onto a dumbbell-shaped rod, where [n] denotes the total number of interlocked molecules.
Prof Heath's team did this by creating a new compound, called rotaxane
, which grows in a crystalline structure.
The gates are built of a layer of synthetic material, called rotaxane
, one molecule thick.
Topics addressed include bioactive macrocyclic peptides and peptide mimics, macrocycles by ring-closure metathesis, supramolecular macrocycle synthesis by H-bonding assembly, cucurbiturils, tetra-urea calixarenes, shape-persistent macrocycles based on acetylenic scaffolding, supramolecular 3D architectures by metal-directed assembly of synthetic macrocycles, new properties and reactions in self-assembly M6L4 coordination cages, anion-binding macrocycles, and rotaxane
and catenane synthesis.