Temperature-Responsive Fluorescent Organoplatinum(II) Metallacycles

J Am Chem Soc. 2018 Jun 20;140(24):7723-7729. doi: 10.1021/jacs.8b04452. Epub 2018 Jun 5.

Abstract

The synthesis, characterization, and temperature-responsive properties of two fluorescent organoplatinum(II) metallacycles are reported. Metallacycles M1 and M2 were prepared via the coordination-driven self-assembly of a 120° triarylamine ligand L1 and a 120° diplatinum(II) acceptor Pt-1 or 180° diplatinum(II) acceptor Pt-2, respectively. M1 and M2 are hexagonal metallacycles, comprising of three or six freely rotating anthracene pendants on their periphery, respectively. In response to the temperature variation between -20 and 60 °C, the ligand displays irregular emission changes, whereas both metallacycles show reversible absorption and emission spectral changes in THF. The changes in their green emission intensity also exhibit a linear correlation with the temperature variation, with an average sensitivity of -0.67% and -0.77% per °C for M1 and M2, respectively. Furthermore, in coordinating solvents, such as DMF and CH3CN, M1 and M2 show different behaviors: in the lower temperature range, i.e., below 30 °C, their spectral changes are similar to those observed in THF; however, at a higher temperature the metallacycles were presumably destroyed by the solvents and displayed ratiometric fluorescent responses, including a cyan emission of the ligand L1.

Publication types

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

MeSH terms

  • Coordination Complexes / chemical synthesis
  • Coordination Complexes / chemistry*
  • Fluorescence
  • Fluorescent Dyes / chemical synthesis
  • Fluorescent Dyes / chemistry*
  • Ligands
  • Models, Chemical
  • Molecular Structure
  • Organoplatinum Compounds / chemical synthesis
  • Organoplatinum Compounds / chemistry*
  • Quantum Theory
  • Solvents / chemistry
  • Temperature

Substances

  • Coordination Complexes
  • Fluorescent Dyes
  • Ligands
  • Organoplatinum Compounds
  • Solvents