[structure: see text] Two new anthracene-containing azoalkanes (1 and 2) absorb UV light 600 times more strongly than simple azoalkanes. Intramolecular energy transfer from excited singlet anthracene to the azo group is nearly complete, but despite the close proximity of the two chromophores, 1 and 2 continue to exhibit anthracene fluorescence. Thermolysis of these compounds in the presence of monomers