White polymeric light-emitting diodes (WPLEDs) from a single polymer system were developed by incorporating 2,3-bis(4-methyloxyphenyl)quinoxaline and 5,8-bis(N,N-diphenylamino)-2,3bis(4-methyloxyphenyl)quinoxaline into poly(9,9-dioctylfluorene). All copolymers showed good thermal stability with 5% weight loss temperatures above 420 °C, and glass transition temperatures ranged from 86 to 143 °C. Electroluminescence (EL) devices with indium tin oxide/poly(3,4-ethylenedioxythiophene):poly-(styrenesulfonic acid)/emission layer/Ca/Ag were found to emit white light with Commission Internationale de l'Eclairage (CIE) coordinates of (0.33, 0.40) and (0.30, 0.36). These devices exhibit a highest brightness of 12 300 cd/m 2 and a maximum current efficiency of 2.56 cd/A.

A series of new low‐band gap copolymers based on dioctyloxybenzo[1,2‐b;3,4‐b′] dithiophene and bis(2‐thienyl)‐2,3‐diphenylbenzo[g]quinoxaline monomers have been synthesized via a Stille reaction. The effect of different functional groups attached to bis(2‐thienyl)‐2,3‐diphenylbenzo[g]quinoxaline was investigated and compared with their optical, electrochemical, hole mobility, and photovoltaic properties. Polymer solar cell (PSC) devices of the copolymers were fabricated with a configuration of ITO/ PEDOT: PSS/copolymers: PCBM (1:4 wt ratio)/Ca/Al. The best performance of the PSC device was obtained by using PbttpmobQ as the active layer. A power conversion efficiency of 1.42% with an open‐circuit voltage of 0.8 V, a short‐circuit current (JSC) of 5.73 mA cm−2, and a fill factor of 30.9% was achieved under the illumination of AM 1.5, 100 mW cm−2. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

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Cycloaddition reaction of the 7‐azaindolizines (I) with two equivalents of dimethyl acetylenedicarboxylate (II) gives modest yields of the pyrridopyrrolopyridazines (III).