Rod-shaped thiocyanic compounds based on a 4-benzoyloxy-biphenyl mesogen were prepared by nucleophilic substitution with a thiocyanic salt. The number of carbon atoms in one terminal alkyloxy chain was 6
8 and 10. The mesomorphic properties of the synthesized compounds were characterized by means of polarized optical microscopy and differential scanning calorimeter. The results demonstrated that the thiocyanic compounds exhibited thermotropic smectic A and nematic phases. The isotropic point of the liquid crystals decreased with the increase in length of the terminal alkyloxy chain.
关键词
Keywords
references
Yoshio M, Kagata T, Kato T, et al. One-dimensional ion-conductive polymer films: alignment and fixation of ionic channels formed by self-organization of polymerizable columnar liquid crystals[J]. J. Am. Chem. Soc., 2006, 128(16): 5570-5577.[2] Tiitu M, Torkkeli M, Serimaa R, et al. Self-assembly and flow alignment of protonically conducting complexes of polystyrene-block-poly(4-vinylpyridine) diblock copolymer with phosphoric acid[J]. Solid State Ionics, 2005, 176(13-14):1291-1299.[3] Haramoto Y, Koide S, Okubo Y, et al. New liquid crystal materials with a terminal alkyl sulfonic acid unit[J]. Mol. Cryst. Liq. Cryst., 2006, 451(1):121-126.[4] Mussinan C J, Keelan M E. Sulphur compounds in foods . Washington, DC:American Chemical Society, 1994:106.[5] Prakash O, Kaur H, Batra H, et al. -thiocyanation of carbonyl and -dicarbonyl compounds using (dichloroiodo)benzene-lead(II) thiocyanate[J]. J. Org. Chem., 2001, 66(6):2019-2023.[6] Kuo T, O'Brien T F. Cast polydiacetylene films from diacetylenic glutamate lipids[J]. Langmuir, 1991, 7(3):584-589.[7] Orzeszko B, Melon-Ksyta O, Orzeszko A. An efficient, facile, and fast synthesis of 4-alkoxy-4'-hydroxybiphenyls[J]. Synthetic Communications, 2002, 33(22):3425-3429.[8] Acree W E, Chickos J S. Phase change enthalpies and entropies of liquid crystals[J]. J. Phys. Chem. Ref. Data, 2006, 35(3):1051-1330.