Abstract
Photochromic systems have been used to achieve a number of engineering functions such as light energy conversion, molecular motors, pumps, actuators, and sensors. Key to practical applications is a high efficiency in the conversion of light to chemical energy, a rigid structure for the transmission of force to the environment, and directed motion during isomerization. We present a novel type of photochromic system (diindane diazocines) that converts visible light with an efficiency of 18 % to chemical energy. Quantum yields are exceptionally high with >70 % for the cis–trans isomerization and 90 % for the back‐reaction and thus higher than the biochemical system rhodopsin (64 %). Two diastereomers (meso and racemate) were obtained in only two steps in high yields. Both isomers are directional switches with high conversion rates (76–99 %). No fatigue was observed after several thousands of switching cycles in both systems.
Highlights
Induced cis–trans isomerizations are the key processes in the perception of light and for retinal-based photosynthesis.[1]
We set out to systematically improve the performance of the most frequently used artificial photoswitch azobenzene 1 and have been successful in enhancing all above parameters
The conversion wavelengths are shifted into the visible range, the quantum yields improved to 70– 90 %, the strain energy produced increased to 18 kcal molÀ1, the molecular switching movement is directional, the molecular framework is rigid, and the fatigue resistance amounts to at least a few thousand cycles
Summary
Induced cis–trans isomerizations (e.g. of retinal) are the key processes in the perception of light and for retinal-based photosynthesis (pumping protons through ion channels in halophilic bacteria).[1]. The conversion wavelengths are shifted into the visible range, the quantum yields improved to 70– 90 % (surpassing even the most efficient biological system rhodopsin), the strain energy produced increased to 18 kcal molÀ1, the molecular switching movement is directional, the molecular framework is rigid (no conformational degrees of freedom), and the fatigue resistance amounts to at least a few thousand cycles.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
