Odd-Carbon Alkyl-Substituent Effect on Liquid Crystalline Properties of Discotic Hexa-Peri-Hexabenzocoronene Molecule
Hexa-peri-Hexabenzocoronene (HBC), as the smaller graphene fragment consisting of 13 fused benzene rings, possesses a strong tendency to stack together via π-electronic interaction. In this paper, the 1,2-(4-bromomethyl-1-yl) acetylene was alkylated by Grignard reagent to form corresponding 1,2-bis(p-pentadecanylphenyl)acetylene. Cobalt(0)-catalyzed cyclotrimerization was carried out to give hexaphenylbenzene analogue. This step was followed by intramolecular cyclodehydrogenation to yield the desired product HBC-C15. The identity and purity of the new compound was confirmed by UV-vis spectrometer and 1H NMR spectrum. Its thermal behavior and self-assembly were studied by differential scanning calorimetry and polarizing optical microscopy.
Zhong Cao, Xueqiang Cao, Lixian Sun, Yinghe He
X. Y. Liu et al., "Odd-Carbon Alkyl-Substituent Effect on Liquid Crystalline Properties of Discotic Hexa-Peri-Hexabenzocoronene Molecule", Advanced Materials Research, Vols. 239-242, pp. 3358-3361, 2011