Synthesis and properties of unsymmetrically extended π-electronic conjugation system of octaethylporphyrin(Ni)–dihexybithiophene–octaethylporphyrin(Pd) connected with diacetylene linkage

Orientational isomers of the diacetylene-group connected dihexybithiophene (DHBTh) derivatives have been synthesized, in which the different octaethylporphyrin (OEP(M); M=Ni or Pd) rings are attached at the ends. Reflecting the unsymmetrical structural feature, the peculiar electronic properties of the extended OEP(Ni)–DHBTh–OEP(Pd) system were observed.