Preparation and properties of new π-conjugated polyquinoxalines with aromatic fused rings in the side chain

Summary New π-conjugated polyquinoxalines with aromatic fused rings in their side chain have been prepared. Dehalogenative organometallic polycondensation of 5,8-dibromo2,3-b]-acenaphthenequinoxaline and 5,8-dibromo2,3-b]phenanthrenequinoxaline with a zerovalent nickel complex afforded poly(2,3-b]acenaphthenequinoxaline-5,8-diyl) (P(5,8-Qx(ace))) and poly(2,3-b]phenanthrenequinoxaline-5-8-diyl) (P(5,8-Qx(phen))) in high yields. P(5, 8-Qx(ace)) had an η] value of 0.23 dL g⁻¹ and showed absorption and photoluminescence peaks at 445 and 565 nm, respectively. (P(5,8-Qx(phen))) gave absorption and photoluminescence peaks at 400 and 514 nm, respectively. XRD data indicated formation of ordered structures of the polymers in the solid. Preparation of related copolymer with thiophene is also reported. Received: 15 February 2000/Accepted: 2 March 2000