Pentiptycene-Derived Molecular Brakes

In this thesis, we report on design and synthesis of a series of light-driven molecular brakes 1R and 2R. The molecular brakes are constructed by the three-dimensional rigid pentiptycene structure and light responsive stilbene scaffold. The switching process between the brake-off and the brake-on states relies on the stilbene E-Z photoisomerization. We have tested different substituents on the styryl moiety and discussed the steric and electronic effects between the rotor and the brake components. By introducing the photoinduced electron transfer (PET) module, we created an anti-lock brake system (ABS). The ABS operation is improved with elongated chromophores due to adiabatic isomerization and fluorescence properties.