Electrostatically-gated molecular rotors.

The ability to control molecular-scale motion using electrostatic interactions was demonstrated using an N -phenylsuccinimide molecular rotor with an electrostatic pyridyl-gate. Protonation of the pyridal-gate forms stabilizing electrostatic interactions in the transition state of the bond rotation process that lowers the rotational barrier and increases the rate of rotation by two orders of magnitude. Molecular modeling and energy decomposition analysis confirm the dominant role of attractive electrostatic interactions in lowering the bond rotation transition state.