Synthesis and Electrogenerated Chemiluminescence of Donor-Substituted Phenylethynylcoumarins

Two series of donor-bearing phenylethynylcoumarins have been synthesized, and their photophysical
properties have been evaluated. Chemiluminescence was observed through the annihilation of their
electrogenerated radical ions and was found to be only slightly affected by the presence of various
donor groups on the phenyl moiety linked through the C−C triple bond. The overall properties of
the two series of compounds are discussed with respect to their structures. The observed electronic
absorption properties are explained with the help of computational studies.