文摘
The electrochemistry and the electrogenerated chemiluminescence (ECL) of the BODIPY species (2,6-diethyl-1,3,5,7-tetramethyl-8-n-pentyl-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene, i.e., B8-n-pentyl), an aromatic monomer (B8-phenyl), and a closely related dimer were examined. The B8-n-pentyl species with the n-pentyl donor chain in the meso position shows good electrochemical behavior in MeCN with the formation of stable radical ions. The ECL emission is characterized by long-wavelength emission during consecutive oxidation and reduction steps. This is attributed to aggregate formation on radical ion annihilation, the extent of which increased with increasing concentration of the compound. The B8-phenyl electrochemistry also shows stable radical ions. However, B8-phenyl with the meso phenyl group ECL emission does not show any long-wavelength emission. The synthesized dimer closely related to this species shows two electrochemical oxidations with peak separations of 0.5 V and two reductions with peak separations 0.2 V, which corresponds to a high degree of intermolecular interactions in the molecule. The growth of additional electrochemical peaks during the oxidation and reduction of B8-n-pentyl was not seen, and both radical ions were stable, suggesting that emitting secondary products were not formed.