Abstract
During the interaction of 1,3-dibromoazulene, as well as 2,7-Bis(3-bromoazulen-1-yl)-9,9-dioctyl-fluorene with 2,2'-(9,9-dioctyl-9H-fluorene-2,7-diyl)bis(1,3,2-dioxaborinane) under Suzuki − Miyaura cross-coupling conditions, azulene conjugate copolymers were synthesized: poly[2,7-(9,9-dioctylfluorenyl)-alt-(1ꞌ,3ꞌ - azulenyl)] and poly[1,3-bis(9ꞌ,9ꞌ-dioctylfluoren-2ꞌ-yl)azulenyl]-alt-[1ꞌꞌ,3ꞌꞌ - azulenyl]. It is shown that neutral solutions of the obtained copolymers are nonfluorescent, but they become luminescent upon addition of trifluoroacetic acid. The «launching» of fluorescence occurs as a result of the formation of a 6 π-electron azulenyl cation, which rearranges the general electronic character of polymers, in particular, HOMO-LUMO levels and band gap.