Direct Observation of Hemithioindigo-Motor Unidirectionality

Angew. Chem. Int. Ed., Volume 56, Issue 46, Pages 14536–14539, DOI: 10.1002/anie.201708178
Angew. Chem. Int. Ed., online article

Hemithioindigo molecular motors undergo very fast unidirectional rotation upon irradiation with visible light, which has prevented a complete analysis of their working mechanism. In this work, we have considerably slowed down their motion by using a new synthesis for sterically hindered motor derivatives. This method allowed the first observation of all four intermediate states populated during rotation. The exact order in which each isomeric state is formed under irradiation conditions was elucidated using low temperature 1H NMR spectroscopy in conjunction with other analytical methods. At the same time, complete unidirectionality could also be directly shown. Access to slowly rotating hemithioindigo motors opens up a plethora of new applications for visible-light-induced unidirectional motions, especially in areas such as catalysis, smart materials, and supramolecular chemistry.
 

CIPSM Movie
LMUexcellent
TU München
MPG
Helmholtz München
MPI of Neurobiology
MPI of Biochemistry