C. Beginn et al., SYNTHESIS OF POLY(9-HEXYL-3,6-CARBAZOLYLENEETHYNYLENE) AND ITS MODEL COMPOUNDS, Macromolecular chemistry and physics, 195(7), 1994, pp. 2353-2370
The novel conjugated polymer poly(9-hexyl-3,6-carbazoylyleneethylene)
(16) was prepared by palladium-catalyzed polycondensation of 3,6-diiod
o-9-hexylcarbazole and 3,6-diethynyl-9-hexylcarbazole. The polymer has
a number-average molecular weight (M(n)BAR) of 3 100. By fractionatio
n a polymer with M(n)BAR of 6400 was obtained. Besides polycondensatio
n, a palladium-catalyzed bond-opening polymerization of the triple bon
ds occurs as a side reaction which can be partially suppressed by lowe
ring the reaction temperature to 60-degrees-C. Two well-defined model
compounds of the title polymer, a dimer and a trimer, were synthesized
by stepwise reaction. The mass spectra of both model compounds demons
trate the remarkably high stability of the radical cations of the dime
r and trimer. Since the trimer forms a stable glass it is ideally suit
ed for the investigation of its photoconductive properties. First expe
riments carried out by the Time-of-Flight technique showed remarkably
high carrier mobilities up to 2 . 10(-4) cm2/(V . s) for the trimer.