Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 10, 2004
Previous Article Next Article

Exploring the boundaries of a light-driven molecular motor design: new sterically overcrowded alkenes with preferred direction of rotation

Author affiliations

Abstract

Insight in the steric and electronic parameters governing isomerization processes in artificial molecular motors is essential in order to design more advanced motor systems. A subtle balance of steric parameters and the combination of helical and central chirality are key features of light-driven unidirectional rotary molecular motors constructed so far. In an approach to decrease the steric hindrance around the central olefinic bond (rotary axis) and thereby lowering the energy barrier for helix inversion resulting in an increased rotation rate, the boundaries of our molecular motor design are explored. In a new design of a light-driven molecular motor based on a sterically overcrowded alkene the methyl substituent adjacent to the stereogenic center, which is responsible for the control of the direction of rotation, is shifted one position away from the fjord region of the molecule compared to the second-generation motor systems. In contrast to previously developed light-driven molecular motors, there is a preference for the methyl substituent to adopt a pseudo-equatorial orientation. Nevertheless, this new type of motor is capable of functioning as a rotary molecular motor, albeit not with full unidirectionality. Under the combined influence of light and heat, there is a preferred clockwise rotation of one half of the molecule. Surprisingly, the effect of shifting the methyl substituent on the energy barrier for helix inversion is small and even a slight increase in the barrier is observed.

Graphical abstract: Exploring the boundaries of a light-driven molecular motor design: new sterically overcrowded alkenes with preferred direction of rotation

Back to tab navigation

Supplementary files

Article information


Submitted
13 Feb 2004
Accepted
19 Mar 2004
First published
26 Apr 2004

Org. Biomol. Chem., 2004,2, 1531-1541
Article type
Paper

Exploring the boundaries of a light-driven molecular motor design: new sterically overcrowded alkenes with preferred direction of rotation

R. A. van Delden, M. K. J. ter Wiel, H. de Jong, A. Meetsma and B. L. Feringa, Org. Biomol. Chem., 2004, 2, 1531
DOI: 10.1039/B402222J

Social activity

Search articles by author

Spotlight

Advertisements