94459-00-4Relevant academic research and scientific papers
Synthesis of Hydroxy-Substituted p-Terphenyls and some Larger Oligophenylenes via Palladium on Charcoal Catalyzed Suzuki-Miyaura Reaction
Jansa, Josef,?ezní?ek, Tomá?,Jambor, Roman,Bure?, Filip,Ly?ka, Antonín
, p. 339 - 350 (2017/02/05)
A ligand-free heterogeneous palladium on charcoal (Pd/C)-catalyzed Suzuki-Miyaura cross-coupling has been performed. The series of substituted p-terphenyls were prepared in very good yields without exclusion of air and with low catalyst loadings. Moreover, the developed environmentally benign and scalable protocol enables to use electron poor and sterically hindered boronic acids. (Figure presented.).
Synthesis and properties of light-emitting polythiophene derivatives bearing terphenyl mesogenic pendant
Chen, Lie,Chen, Yiwang,Zhou, Weihua,Li, Fan,He, Xiaohui,Tang, Ben Zhong
experimental part, p. 70 - 83 (2011/05/03)
A series of polythiophenes containing terphenyl mesogenic side chain at the third position through ester bonding was synthesized by dehalogenative polycondensation. The thiophene monomers 2,5-bromo-3-{[(4-(4'-cyano) terphenyloxy)carbonyl]-methyl]}-thiophene [M(CN)] and 2,5-bromo-3-{[(4-(4'- methoxy)terphenyloxy)-carbonyl]methyl}-thiophene [M(OCH3)] were prepared via Suzuki reation and esterification reactions, in sequence. The structures and properties of the monomers and polymers were characterized and evaluated with nuclear magnetic resonance, infrared spectroscopy, thermogravimetry, differential scanning calorimetry, polarized optical microscopy, ultraviolet spectroscopy, and photoluminescence. All of the polymers were stable, losing little of their weights when heated to 300°C. The polymers showed good solubility and could be dissolved in common solvents such as CHCl3, THF, DMF, etc. The monomers exhibited enantiotropic SmAd phases with a bilayer arrangement in the heating and cooling processes. Due to short spacer methylene ester between the bulk terphenyl mesogenic side chain and rigid polythiophene main chain, the polymers could not exhibit liquid crystallinty at elevated temperature. The existence of the chromophoric terphenyl core endows the polymers with high photoluminescence. When their CH2Cl2 solutions were photoexcited, the polymers emitted a strong UV light about 400nm.
Synthesis and thermal analysis of disubstituted propiolates bearing terphenylene mesogen
Chen, Lie,Chen, Yiwang,Zhou, Weihua,He, Xiaohui,Song, Yanlin,Zhang, Zhijie
experimental part, p. 391 - 397 (2010/09/06)
Novel disubstituted propiolates bearing chromophoric terphenylene mesogenic groups, namely, 40-cyano- 4-terphenylyl-2-octynate M(CN) and 40-methoxyl-4-terphenylyl- 2-octynate M(OCH3) are synthesized, where the terphenyl groups are connected to the C≡C through ester linkage directly. Using transition-metal catalysts such as the classical MoCl 5- and WCl6-based metathesis catalysts, the polymerization of the M(CN) and M(OCH3) are carried out in a series of different solution, however, did not obtain any products. It suggests that the WCl 6- and MoCl5-based catalysts are poisoned by the polar groups, on the other hand, the bulk terphenyl groups and the long alkyl chain around the C≡C bond might inhibit the reaction. M(CN) displays monotropic nematicity, whereas M(OCH3) exhibits enantiotropic nematicity and smecticity (SmAd) with a bilayer arrangement when cooled and heated. Ultraviolet spectroscopy and photoluminescence measurements also show that the terphenyl groups endow disubstituted propiolates with strong UV light absorption and high photoluminescence. Akademiai Kiado, Budapest, Hungary 2009.
Synthesis and Properties of High-Temperature Mesomorphic Polysiloxane Solvents: Biphenyl- and Terphenyl-Based Nematic Systems
Apfel, M. A.,Finkelmann, H.,Janini, G. M.,Laub, R. J.,Luehmann, B.-H.,et al.
, p. 651 - 658 (2007/10/02)
The synthesis and characterization of a variety of mesomorphic (liquid-crystalline) side-chain polysiloxane (MEPSIL) solvents, said to be useful as gas chromatographic stationary phases, are described and discussed.The synthetic scheme is based upon the hydrosilation reaction that occurs when 4-(allyloxy)benzoyl esters are contacted with poly(methylsiloxane) in the presence of a dicyclopentadienylplatinum(II) catalyst, while product characterization is carried out by IR, NMR, GC, DSC, elemental analysis, and direct-observation hot-stage light-polarized microscopy.Selectivity of the MEPSIL phases is shown to differ very substantially from those exhibited by all other common GC solvents.The MEPSIL found overall to be the best suited as a GC stationary liquid exhibits a melting point of 139 deg C (k -> n) and a nematic/isotropic (n -> i) transition temperature of 319 deg C, while the practical operating limits of the material span 150 to in excess of 300 deg C.
