Synthesis of unsymmetric triphenylene discotic liquid crystals with a semi-fluorinated chain and the influence of fluorophobic effect on mesogenic behavior
The fluorophobic effect of the semi-fluorinated chain of discotic molecules efficiently improves the stability of columnar mesophase.Low symmetric discogens exhibit decreased melting points and wide mesophase ranges.A series of triphenylene derivatives 1,C18H6(OCnH2n+1)4(OMe)(O2CC2H4C6F13),and their...
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Published in | Science China. Chemistry Vol. 52; no. 8; pp. 1244 - 1252 |
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Main Authors | , , , , |
Format | Journal Article |
Language | English |
Published |
Heidelberg
SP Science in China Press
01.08.2009
Springer Nature B.V |
Subjects | |
Online Access | Get full text |
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Summary: | The fluorophobic effect of the semi-fluorinated chain of discotic molecules efficiently improves the stability of columnar mesophase.Low symmetric discogens exhibit decreased melting points and wide mesophase ranges.A series of triphenylene derivatives 1,C18H6(OCnH2n+1)4(OMe)(O2CC2H4C6F13),and their hydrocarbon analogues 2,C18H6(OCnH2n+1)4(OMe)(O2CC8H17),n = 4―8,were synthesized for the investigation of the influence of semi-fluorinated peripheral chain and molecular symmetry on mesomorphism.The structures were characterized with 1H NMR and MS.The mesomorphism was studied with differential scanning calorimetry(DSC) and polarizing optical microscopy(POM).The results showed that all triphenylene derivatives exhibited enantiotropic columnar mesophase.The semifluorinated triphenylenes 1a―1e displayed higher melting points and clearing points than their hydrocarbon analogies 2a―2e.Most of them were in columnar mesophase at room temperature. |
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Bibliography: | YANG GaoFan,ZHAO KeQing,YU WenHao,HU Ping & WANG BiQin College of Chemistry and Materials Science,Sichuan Normal University,Chengdu 610066,China 11-5839/O6 |
ISSN: | 1674-7291 1006-9291 1869-1870 1862-2771 |
DOI: | 10.1007/s11426-009-0113-0 |