Synthesis and characterization of di- and tri- substituted benzamide derivatives as bis-swallow-tailed mesogens

This study is concerned with the synthesis and characterization of some new liquid crystalline compounds derived from di- and tri-hydroxy benzoic acids with bis-swallow tailed which called N,N`-1,4-phenyl-bis[3`,5`-disubstituted benzamide] , N,N`-4,4`-biphenyl-bis[3``,5``-disubstitutedbenzamide], N,N`-1,4-phenyl-bis[3`,4`,5`-trisubstitutedbenzamide] and N,N`-4,4`-biphenyl-bis[3``,4``,5``-tri substituted benzamide] which were synthesized according to the following schemes(1, 2, 3, 4):