Triphenylene compounds, columnar phases

Investigation of symmetric and non-symmetric triphenylenes combining three fluorinated and three non-fhiorinated chains (compounds 149 and 150 in Fig. 40) has shown that these compounds can possess a higher stability of the columnar phases compared to those with all chains semiperfluorinated (compound 148), whereas the distribution of the fluorinated chains (symmetric vs. non-symmetric) does not play a significant role [272],... 

Discotic architectures that use a central triphenylene core with six peripheral triphenylene units also exhibit colunmar mesophases, and these are commonly called star-like liquid crystals. Compoimd 28 is a very large molecule that uses flexible spacers to attach peripheral triphenylene units to a central discotic core in a star-like manner. The hexagonal columnar phase of compound 28 has been identified as hexagonal. Such stractmes are ohgomeric and could almost be considered polymeric (see Chapter 5). 

Optically active esters of benzene, triphenylene and truxene have been studied [40], The triphenylene and truxene derivatives (structures 2 and 4, respectively, with R = (-h)- or (-)-CH3-(CH2)5-CH(CH3)-CH2-CO O) do show mesophases, but of the non-chiral columnar type. In other words, this chiral substituent does not change the nature of the phases. The benzene derivative is non-mesomorphic. However, when these compounds are mixed with... 

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