BODIPYs with Chalcogenophenes at Boron: Synthesis and Properties

Reported herein are the synthesis and characterizationof BODIPYsbearing heterocycles at boron. To synthesize this series, variouschalcogenophenes (furan, thiophene, selenophene, and tellurophene)were lithiated and then used as nucleophiles to attack the boron centerof a parent F-BODIPY. Compounds in the series werecompared with respect to their photophysical and structural properties,and trends were discussed. By virtue of the "heavy atom effect",as the mass of the heterocycle appended to the BODIPY core increases,compounds exhibit a higher singlet oxygen quantum yield. The BODIPYwith tellurophene at boron exhibits the highest quantum yield (& phi;(& UDelta;) = 0.68) in the series and reduced emission (& phi;(f) = 0.01).