Columnar Discotic Mesophases from Novel Non-symmetrically Substituted (Octylsulfanyl) Porphyrazines Molecular Crystals and Liquid Crystals

Synthesis and mesomorphism of novel non-symmmetric mono beta-aryl (octylsulfanyl)porphyrazines and their Ni(II) complexes were reported. A recently disclosed asymmetrization procedure led to mono beta-bromo substituted porphyrazines, which provided access to aryl substituted derivatives through Suzuki cross-coupling. UV-Vis spectroscopy showed a bathochromic shift for bromine and aryl substituted nickel complexes. Optical Microscopy and DSC showed that Br derivatives 3a-3b and H-heptakis Ni(II) complex 2b display two columnar mesophases (Col(h) and Col,) stable even at RT and a wide Delta T (100 degrees C). Introduction of the aryl substituent on the macrocycle caused the appearance of only the Col(h) mesophase and lower Delta T.