Synthesis and characterization of novel thienylpyridazine derivatives

Abstract

Recently, the exploration of thiophene π-conjugated systems functionalized with donor-acceptor groups has greatly expanded due to the increased interest in optoelectronic, photovoltaic and OLED applications. This type of molecules are highly targeted due to the easy tuning of the photophysical properties by small structural modifications 1-7. A few thienylpyridazines were synthesized as part of an on-going research directed to the development of donor-acceptor substituted heterocyclic systems for several optical (linear and nonlinear)8-9 and DSSCs applications. In this communication we report the synthesis and the photophysical characterization of novel thienylpyridazine derivatives, functionalized in position 3, with different donor groups (thiophene, pyrrole and N,N-dialkylphenylamine). The diazines were synthesized by Suzuki coupling of 3-bromo-6-(thiophen-2-yl)pyridazine with commercially available (hetero)aryl-boronic acids. On the other hand, precursor 3-bromo-6-(thiophen-2-yl)pyridazine was prepared by reaction of a thienylpyridazinone with POBr3 10.