Synthesis and Characterization of Far-Red Emissive Boron-Based Triads Showing Large Stokes Shifts: Optical, TRANES, and Electrochemical Studies

J Org Chem. 2022 Mar 18;87(6):3967-3977. doi: 10.1021/acs.joc.1c02595. Epub 2022 Mar 7.

Abstract

Herein, we report the design and synthesis of far-red emissive boryl-thiophene-BODIPY triads 1-3. The π-conjugation length and electronic communication between borane and BODIPY moieties are tuned by judiciously varying the size of the oligothiophene spacer in these triads (1, terthiophene; 2, quarterthiophene; and 3, pentathiophene). Conjugates 1-3 showed intriguing triple emissions in the blue to far-red regions. Detailed optical, time-resolved decay kinetics, time-resolved area-normalized emission spectra (TRANES), fluoride binding, and computational studies suggest that the multiple emissions in these triads are due to an inefficient transfer of energy from the boryl-oligothiophene to the BODIPY unit. In addition, all of the conjugates showed a ratiometric fluorescence response to fluoride ions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Boranes* / chemistry
  • Boron* / chemistry
  • Fluorides
  • Spectrometry, Fluorescence

Substances

  • Boranes
  • Boron
  • Fluorides