Simple Polyphenyl Zirconium and Hafnium Metallocene Room-Temperature Lumophores for Cell Imaging

Zirconium and hafnium metallocene dihalides based on simple polyphenyl cyclopentadienes are stable room-temperature lumophores with large Stokes shifts, emitting from states with substantial LMCT character. Their synthesis is described, including by a rapid solvent-free approach compatible with the lifetime of PET-active isotopes (89Zr). Preliminary experiments indicate the viability of these species as lumophores for fluorescence cell-imaging microscopy.