195877-12-4Relevant academic research and scientific papers
Bimetal Cooperatively Catalyzed Arylalkynylation of Alkynylsilanes
Chen, Xing,Li, Mengke,Liu, Zhipeng,Yang, Can,Xie, Haisheng,Hu, Xinwei,Su, Shi-Jian,Jiang, Huanfeng,Zeng, Wei
supporting information, p. 6724 - 6728 (2021/09/08)
An unprecedented Pd/Rh cooperatively catalyzed arylalkynylation of alkynylsilanes was developed to merge an alkynylidene moiety with benzosilacycle. These silaarenes possess a particular aggregation-induced emission behavior. Mechanistic investigations demonstrate that the relay trimetallic transmetalation plays a pivotal role in governing this transformation.
Acetylene derivatives, and liquid crystal composition and liquid crystal display device each comprising the same
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, (2008/06/13)
The present invention provides new liquid crystalline compounds having a high optical anisotropy value and excellent compatibility with the other liquid crystals, and liquid crystal composition comprising the compounds.The liquid crystalline compounds are represented by the general formula (1): wherein H1, H2, H3, H4, H5, H6, H7, H8, H9, H10, H11 and H12, each independently, represent H, F or Cl, at least one of H1, H2, H3, H4, H9, H10, H11 and H12 is F or Cl, R1 represents an alkyl group of C1-20, in which methylene groups may be replaced by —O—, —S—, —Si—, —CH=CH— or —C≡C—, any hydrogen atoms may be replaced by a halogen atom, and Y1 is replaced by R1, F, Cl, Br, I or a cyano group.
Synthesis and Physical Properties of Asymmetric Diphenyldiacetylenic Liquid Crystals
Meng, H.-H. B.,Dalton, L. R.,Wu, S.-T.
, p. 303 - 314 (2007/10/02)
Fifty-six asymmetric diphenyl-diacetylene liquid crystal homologs including dialkyl, alkyl-alkoxy, cyano-alkyl, chloro-alkyl, fluoro-alkyl, difluoro-alkyl, lateral chloro-substituted fluoro-alkyl (or alkoxy), lateral fluoro-substituted asymmetric dialkyl, and vinyl-alkyl are synthesized and their physical properties evaluated.Among these asymmetric diphenyl-diacetylene liquid crystals, many dialkyl homologs exhibit low melting point, wide nematic range, and low heat of fusion.They are ideal host candidates for formulating eutectic mixtures.The polar groups make important contributions to the phase transition temperature, dielectric anisotropy, refractive indices and viscosity.Detailed effects depend on the position of the substitution.These new liquid-crystals compounds and mixtures are particularly useful for electro-optic modulation of infrared radiation. - Keywords: Diphenyl-diacetylenes, eutectic mixtures, electro-optic modulation, physical properties
