CPI (complementary polytopic interaction) stabilised liquid crystal compounds formed by esters of 2-hydroxy-3,6,7,10,11-pentakis(hexyloxy)triphenylene

An improved synthesis of 2-hydroxy-3,6,7,10,11-pentakis(hexyloxy)triphenylene 6 is reported which is based on the oxidative coupling of 2-acetoxy-1-hexyloxybenzene 3 to 3,3',4,4'-tetrakis(hexyloxy)biphenyl 4. Most of the esters of this phenol 7-15, give an enantiotopic Col(h) columnar liquid crystal phase, which is stable over a wide temperature interval. This can be further enhanced by formation of 1 :1 CPI compounds with either 2,3,6,7,10,11- hexakis(4-nonylphenyl)triphenylene {PTP9} 1 or hexakis(4-nonylphenyl)dipyrazino[2,3-f:2',3'-h]quinoxaline {PDQ9} 2. As with other triphenylene derivatives, these additives can also be used to induce liquid crystal behaviour in otherwise non-mesogenic esters.