In Search of Molecular Ratchets


  • J. P. S. Acknowledges Xunta de Galicia and the University of Santiago de Compostela (Spain) for a postdoctoral fellowship. We thank Dr. Chun Zhou for assistance with the spin polarization transfer measurements, Dr. Matthew Bratcher and Prof. W. H. Laarhoven for valuable exchanges of information, and a referee for helpful comments.


original image

Triptycylhelicenes 1 and 2 were examined as molecular rachets (see picture) in which the triptycene serves as the rachet wheel (a) and the helicenes as pawl (b) and spring (c). The ease of rotation of the triptycene wheel depends on the helicene springs and pawls, but do these have any influence on the direction of rotation?