Strongly UV absorbing bifunctional azoalkanes

[GRAPHICS] Two new anthracene-containing azoalkanes (1 and 2) absorb UV light 600 time s more strongly than simple azoalkanes. Intramolecular energy transfer from excited singlet anthracene to the azo group is nearly complete, but despit e the close proximity of the two chromophores, 1 and 2 continue to exhibit anthracene fluorescence. Thermolysis of these compounds in the presence of monomers affords fluorescent labeled polymers. Compounds 1 and 2 are the fi rst azoalkanes to undergo induced decomposition in solution.