The 9,10-dihydrophenanthrene structure as a source of liquid crystals: mesogenic behaviour and spectroscopic properties of 2-benzylideneamino-9,10-dihydrophenanthrenes

Abstract

13 Azomethines have been prepared from 2-amino-9,10-dihydrophenanthrene by reaction with aromatic aldehydes. Those with p-alkoxy, p-cyano or p-phenyl substituents in the aldehydic ring have a nematic mesophase. U.v. spectra, 1 H and 13C n.m.r. spectra, and mass spectra of the series are discussed. Mass spectra show that ortho-substituents in the aldehydic ring substantially modify the fragmentation pattern.