Azobenzene-Based Organic Salts with Ionic Liquid and Liquid Crystalline Properties was written by Stappert, Kathrin;Muthmann, Johanna;Spielberg, Eike T.;Mudring, Anja-Verena. And the article was included in Crystal Growth & Design in 2015.Related Products of 21252-69-7 This article mentions the following:
Two sets of new azobenzene-based bromide salts are synthesized, and their thermal photochromic properties are studied. Both sets are based on the imidazolium cation. The first set (1) features a sym. biscation where two imidazolium head groups (Im) with different alkyl chains (Cn) are connected to a central azobenzene unit (Azo): [Azo(C1-Im-Cn)2]; n = 6, 8, 10, 12, 14. The other one contains an n-alkyl-imidazolium cation (Cn-Im) bearing a terminal azobenzene unit (C1-Azo) substituted with an alkoxy chain (O-Cm) of either two (2) or six (3) carbon atoms: [C1-Azo-O-Cm-Im-Cn]; m = 2, n = 8, 10, 12 and m = 6, n = 8, 10, 12, 14, 16. For both cation classes, the influence of alkyl chains of varying length on the thermal phase behavior was investigated by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). For five compounds (Azo(-C1-Im-C12)2 (1d), Azo(-C1-Im-C12)2 (1e), C1-Azo-O-C2-Im-C10 (2b), C1-Azo-O-C2-Im-C12 (2c), and C1-Azo-O-C6-Im-C16 (3e)), the formation of a liquid crystalline phase was observed The biscationic salts (1) are all comparatively high melting organic salts (180-240 °C), and only the two representatives with long alkylchains (C12 and C14) exhibit liquid crystallinity. The monocationic salts with an O-C2 bridge (2) melt between 140 and 170 °C depending on the alkyl chain length, but from an alkyl chain of 10 and more carbon atoms on they form a smectic A liquid crystalline phase. The representatives of the third set with a O-C6 bridge qualify as ionic liquids with m.ps. less than 100 °C. However, only the representative with a hexadecyl chain forms a liquid crystalline phase. Representative single crystals for all sets of cations could be grown that allowed for single crystal structure anal. Together with small-angle X-ray scattering experiments they allow for a more detailed understanding of the thermal properties. Through irradiation with UV-light (320-366 nm) all compounds undergo trans-cis isomerization, which reverses under visible light (440 nm). In the experiment, the researchers used many compounds, for example, 1-Octyl-1H-imidazole (cas: 21252-69-7Related Products of 21252-69-7).
1-Octyl-1H-imidazole (cas: 21252-69-7) belongs to imidazole derivatives. Imidazole is a heterocyclic compound with a five-membered planar ring. It is amphoteric and highly polar. This ring system is present in important biological building blocks, such as histidine and the related hormone histamine.Related Products of 21252-69-7
Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem