1,3,5-Triazine(trithiophenylcarboxylate) esters form metastable monotropic nematic discotic liquid crystal phases

Nematic Triphenyltriazine Triesters and the Induction of the Columnar Mesophase by Fluorine Substitution

“…This contrasts with the series of trithienyltriazines 5, where the monotropic nematic mesophase of the hexyl homolog 5 Hex was reported to show the best resilience against crystallization at room temperature. [31] Whereas the melting points of the homologs with evennumbered alkyl chains are higher than of those with oddnumbered chains (7 Bu and 7 Hex melt higher than 7 Pr and 7 Pent ), the decrease of clearing temperature is almost linear with chain length from 7 Et to 7 Hex (about À 17°C per carbon).…”

“…[8] Related trithienyltriazine trialkylesters 5 show monotropic nematic mesomorphism with linear alkyl chains of at least three carbon atoms (the ethyl derivative being nonmesomorphic in contrast to 1 and 2), and also crystallize upon standing at room temperature; no columnar mesophase is observed. [31] Two isomeric series of triphenyltriazine triesters with threefold symmetry are accessible by trimerization of methyl cyanobenzoates: para isomers 6 and meta isomers 7. The n-alkyl series of para homologs 6 is known [32] and electrochromism has recently been observed with the ethyl homolog, [33] but no mesogenic properties have been reported.…”

Advances in the Chemistry of 2,4,6‐Tri(thiophen‐2‐yl)‐1,3,5‐triazine

“…Taing and co‐workers reported the synthesis of SMs involving s ‐triazine cores substituted with three thiophene carboxylate groups (Scheme 6 ). [88] Nine derivatives with linear, branched, and chiral ester chains were synthesized [ SM6.4(a–i) ] with yields ranging between 14–93 %. Their mesomorphism was studied by polarised optical microscopy, differential scanning calorimetry, and powder X‐ray diffraction.…”

Ditriphenylenothiophene butterfly-shape liquid crystals. The influence of polyarene core topology on self-organization, fluorescence and photoconductivity

“…Similarly, thiophene-fused discotic liquid crystals (DLCs) 16–33 consisting of a π-extended polyaromatic core surrounded by peripheral alkyl chains also display remarkable assets: they spontaneously self-organize into stable columnar mesophases and show unidimensional μ values ranging from 10 −4 up to 10 −2 cm 2 V −1 s −1 . 21,34–37 While developing such DLC-based semiconducting systems, various strategies, including, notably, the extension of π-conjugated polyaromatic cores, 38,39 molecular dynamic motion controlled by intermolecular hydrogen-bonding, 40,41 and nanosegregation by hydrophilic/hydrophobic 6 and fluorophilic/fluorophobic interactions, 42 have been largely considered and successfully applied to promote and enhance charge carrier mobility.…”