Functionalization of 3,5,8-trichlorinated BODIPY dyes

J Org Chem. 2014 Nov 7;79(21):10342-52. doi: 10.1021/jo501969z. Epub 2014 Oct 14.

Abstract

Catalytic hydrogenation of dibenzyl 5-dipyrroketone-2,9-dicarboxylates followed by decarboxylative iodination affords a 2,9-diiododipyrroketone which gives a 2,5,9-trichlorodipyrromethene hydrochloride after nucleophilic addition/elimination, with adventitious chloride to replace the two iodide groups. Treatment with BF3·Et2O gives a 3,5,8-trichloro-BODIPY that readily undergoes regioselective Stille coupling at the 8-position, or homo/mixed couplings at the 3,8- or 3,5- and 8-positions. Stepwise and controlled replacement of the 3,5- and 8-chlorine atoms using Stille reagents results in formation of a completely unsymmetrical trisubstituted BODIPY. Several examples of unsymmetrical BODIPYs were synthesized and characterized using this methodology. Structure features of new BODIPYs are discussed within the context of 14 new X-ray structures, and photophysical parameters of all new BODIPY compounds are reported and discussed.

Publication types

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

MeSH terms

  • Benzyl Compounds / chemistry*
  • Boron Compounds / chemistry*
  • Coloring Agents / chemistry*
  • Crystallography, X-Ray
  • Fluorescent Dyes / chemistry*
  • Hydrogenation
  • Models, Molecular
  • Molecular Structure
  • Porphobilinogen / analogs & derivatives*
  • Porphobilinogen / chemical synthesis
  • Porphobilinogen / chemistry

Substances

  • 2,5,9-trichlorodipyrromethene hydrochloride
  • 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene
  • Benzyl Compounds
  • Boron Compounds
  • Coloring Agents
  • Fluorescent Dyes
  • Porphobilinogen