Rapid synthesis of new discotic liquid crystals based on diquinoxalino[2,3-a:2′,3′-c]phenazine containing hexakis(alkoxy) side arms

The condensation of 1,2-bisalkoxy-4,5-diaminobenzene 2a–e derivatives with freshly prepared hexaketocyclohexane give hexakis(alkoxy)diquinoxalino[2,3-a:2′,3′-c]phenazines in good yield. DSC and polarization microscopy showed HATOC6 has both the crystalline (K) to mesophase (M) and the mesophase (M) to isotropic (I) phase transitions. Importantly, the alkoxy substituted compound synthesized showed an M–I transition because of greater stability, whereas the reported alkyl-thiol decomposes after the mesophase.