Design, Synthesis, and Dynamics of a Green Fluorescent Protein Fluorophore Mimic with an Ultrafast Switching Function

J Am Chem Soc. 2016 Aug 10;138(31):9807-25. doi: 10.1021/jacs.5b10812. Epub 2016 Jul 29.


While rotary molecular switches based on neutral and cationic organic π-systems have been reported, structurally homologous anionic switches providing complementary properties have not been prepared so far. Here we report the design and preparation of a molecular switch mimicking the anionic p-HBDI chromophore of the green fluorescent protein. The investigation of the mechanism and dynamics of the E/Z switching function is carried out both computationally and experimentally. The data consistently support axial rotary motion occurring on a sub-picosecond time scale. Transient spectroscopy and trajectory simulations show that the nonadiabatic decay process occurs in the vicinity of a conical intersection (CInt) between a charge transfer state and a covalent/diradical state. Comparison of our anionic p-HBDI-like switch with the previously reported cationic N-alkyl indanylidene pyrrolinium switch mimicking visual pigments reveals that these similar systems translocate, upon vertical excitation, a similar net charge in the same axial direction.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Anions
  • Cations
  • Ethanol / chemistry
  • Green Fluorescent Proteins / chemistry*
  • Hydrogen-Ion Concentration
  • Methanol / chemistry
  • Motion
  • Photochemistry
  • Pigmentation
  • Software
  • Solvents / chemistry
  • Spectrometry, Fluorescence*
  • Spectrophotometry


  • Anions
  • Cations
  • Solvents
  • Green Fluorescent Proteins
  • Ethanol
  • Methanol