pi-Conjugated polymers based on 1-aminopyrrole and 4-amino-1,2,4-triazole were prepared. Pd-catalyzed organometallic polycondensation gave poly(arylene-ethynylene) (PAE)-type pi-conjugated polymers consisting of BOC-protected 4-amino-1,2,4-triazole (Taz(BOC)) units (BOC = t-butoxycarbonyl). The number average molecular weights (M-n) were determined to be 5200-19,200 using GPC. An alternating copolymer of Taz(BOC) and bithiophene (Th-Th) units, P(Taz(BOC)-Th-Th)(n)-Pd, with an M-n of 10,800 was also prepared by Pd-catalyzed organometallic polycondensation. (Taz(BOC)-Th-Th)(n)-Pd showed a UV-Vis absorption peak at lambda(max) = 425 nm, which is reasonable for a pi-conjugated five-membered ring polymer with a coplanar structure. The deprotection of the BOC group of the polymers proceeded at 200 degrees C; this BOC-deprotection was investigated using a model compound. The optical and electrochemical properties of the pi-conjugated polymers are reported. (C) 2013 Elsevier Ltd. All rights reserved.