Liquid crystals mesomorphic stilbazole complexes

Another approach to get new liquid crystals is the lateral fluorination of the stilbazole ligands,337 which is a common and highly effective tool to exert control over mesomorphism, crystal phase stability, and physical properties. Other modifications include the use of more alkoxy substituents and other alkyl sulfate anions.338-344 Ionic silver amino complexes also display liquid crystalline behavior at rather low temperatures they are of the form [Ag(NH2 -CJl +OJX (X = N03, n = 6,8,10,12,14 X = BF4, = 8,10,12,14).345... 

Having synthesized a number of complexes of monoalkoxystilbazoles, we explored the effect of using various poly(alkoxy)stilbazoles, given the interesting mesomorphism found in polycatenar mesogens (Section VI,A,3). This work is discussed in detail elsewhere 24). Here, we give an overview of the work to enable the reader to see the overall pattern of liquid-crystal behavior and the issues that arise. 

Two homologs of 78a (M = Pt, X = Cl, = 4, 6) were investigated in the formation of LB fdms. "" It was found that better fdms were obtained with the homolog that was mesomorphic at room temperature (n = 6). In the absence of more data, it is difficult to know how strongly this is correlated with the ambient liquid-crystal behavior of the material, or whether it results from a much lower degree of amphipathy due to the shorter chains. For example, well-ordered LB films of Ir(l) stilbazoles (71, see Section X.11.2) have been formed where the mesophase of the complex is found above 85 °C. 

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