Arakawa, Yuki; Komatsu, Kenta; Ishida, Yuko; Tsuji, Hideto published the article 《Thioether-linked azobenzene-based liquid crystal dimers exhibiting the twist-bend nematic phase over a wide temperature range》. Keywords: thioether azobenzene liquid crystal dimer preparation; twist bend nematic phase.They researched the compound: 1,5-Dibromopentane( cas:111-24-0 ).Name: 1,5-Dibromopentane. Aromatic heterocyclic compounds can be divided into two categories: single heterocyclic and fused heterocyclic. In addition, there is a lot of other information about this compound (cas:111-24-0) here.
Two homologous series of sulfur-containing thioether-linked 4-cyanoazobenzene-based liquid crystal (LC) dimers were developed: a sym. series based on 4-cyanoazobenzene arms [(CN)AzoSnSAzo(CN)] and a non-sym. series based on 4-cyanoazobenzene and 4-cyanobiphenyl arms [(CN)AzoSnSCB]. They contained different flexible oligomethylene spacers (CnH2n) consisting of odd numbers of carbon atoms (n = 3, 5, 7, 9, and 11). The sym. (CN)AzoSnSAzo(CN) dimers with n = 5, 7, 9, and 11 showed an elusive monotropic twist-bend nematic (NTB) phase, while all the non-sym. (CN)AzoSnSCB dimers exhibited the NTB phase. Notably, the NTB phase observed for non-sym. (CN)AzoS7SCB could be supercooled to room temperature, leading to a glassy NTB phase. (CN)AzoS9SCB showed a similar tendency accompanied by partial crystallization These are the first reported examples of azobenzene-based LC dimers exhibiting a broad temperature range of NTB phases supercooled to room temperature Such prominent stability of the NTB phase is due to the supercooling effect assisted by the synergy of mol. bend arising from thioether linkages and non-sym. mesogenic arms. The phase-transition temperatures were overall higher for sym. (CN)AzoSnSAzo(CN) than for non-sym. (CN)AzoSnSCB. The difference in the mesogenic arm structures hardly influenced their mol. geometry or anisotropy in terms of entropy changes.
After consulting a lot of data, we found that this compound(111-24-0)Name: 1,5-Dibromopentane can be used in many types of reactions. And in most cases, this compound has more advantages.
Reference:
Chiral nitrogen ligands in late transition metal-catalysed asymmetric synthesis—I. Addressing the problem of ligand lability in rhodium-catalysed hydrosilations,
Nitrogen-Containing Ligands for Asymmetric Homogeneous and Heterogeneous Catalysis