18855-13-5Relevant academic research and scientific papers
Suzuki-Miyaura coupling of halophenols and phenol boronic acids: Systematic investigation of positional isomer effects and conclusions for the synthesis of phytoalexins from pyrinae
Schmidt, Bernd,Riemer, Martin
, p. 4104 - 4118 (2014/05/20)
The Suzuki-Miyaura couplings of o-, m-, and p-halophenols with o-, m-, and p-phenol boronic acids were investigated for all combinations under standardized conditions, using Pd/C as a heterogeneous catalyst and water as a solvent. In the case of iodophenols, conventional heating was used, while for bromophenols significantly better results could be obtained using microwave irradiation. This systematic study revealed that 2,4′-biphenol is particularly difficult to access, irrespective of the starting materials used, but that these difficulties can be overcome by using different additives. The conclusions drawn from this investigation allowed us to identify conditions for the protecting group-free or minimized total synthesis of biaryl-type phytoalexins. These compounds possess antibacterial activity and are produced by fruit trees as a response to microbial infection.
A modulated helical nanofilament phase
Tsai, Ethan,Richardson, Jacqueline M.,Korblova, Eva,Nakata, Michi,Chen, Dong,Shen, Yongqiang,Shao, Renfan,Clark, Noel A.,Walba, David M.
, p. 5254 - 5257 (2013/06/05)
A new liquid crystal phase, denoted modulated helical nanofilament (HNF(mod)), is formed from a very simple class of biphenyl carboxylates lacking the benzylidene aniline moieties typically found in HNF mesogens. The HNF(mod) phase represents a novel kind of nanoparticle possessing stacked aromatic rings, with potential applications in organic electronics. Copyright
Polymerizable compound and liquid crystal composition including it
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Page/Page column 52; 53; 54, (2013/03/27)
Provided is a polymerizable compound with large solubility in a liquid crystal composition and high reactivity irradiated by ultraviolet in the longer wavelength range. Provided is a liquid crystal composition that satisfies at least one of characteristics such as high maximum temperature of a nematic phase, low minimum temperature of a nematic phase, small viscosity, suitable optical anisotropy, large negative dielectric anisotropy, large specific resistance, high stability to ultraviolet light and high stability to heat, or that is suitably balanced between at least two of the characteristics. Provided is the polymerizable compound wherein at least one of a 1,3-phenylene structure and a 2,7-fluorenediyl structure is introduced to the polymerizable compound to give stable displays by forming a polymer with a high degree of polymerization in a PSA device production process using longer wavelengths, the liquid crystal composition includes the compound, and the liquid crystal display device contains the composition.
Aerobic oxidative heck/dehydrogenation reactions of cyclohexenones: Efficient access to meta-substituted phenols
Izawa, Yusuke,Zheng, Changwu,Stahl, Shannon S.
, p. 3672 - 3675 (2013/04/23)
Jockeying for the (meta)position: A new dicationic palladium(II) catalyst, employing a 6,6′-dimethyl-2,2′-bipyridine ligand, promotes both the aerobic oxidative Heck coupling and dehydrogenation reactions of cyclohexenones. These reactions may be combined in a one-pot sequence to enable the straightforward synthesis of meta-substituted phenols (see scheme). Copyright
METHOD OF PRODUCING BIPHENOLIC COMPOUND, NOVEL BIPHENYL COMPOUND AND SYNTHESIS METHOD THEREOF, AND PHARMACEUTICAL COMPOSITION FOR TREATING PARKINSON'S DISEASE
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Paragraph 0158, (2013/11/19)
A method of producing honokiol and analogues thereof, and novel intermediates prepared by virtue thereof are disclosed herein. A pharmaceutical composition for treating Parkinson's disease, which contains honokiol and/or the analogues thereof, is also disclosed herein.
An expedient synthesis of honokiol and its analogues as potential neuropreventive agents
Tripathi, Subhankar,Chan, Ming-Huan,Chen, Chinpiao
supporting information; experimental part, p. 216 - 221 (2012/02/15)
An efficient synthesis of honokiol with Suzuki-Miyaura cross coupling obtained an overall yield of 45%. The proposed approach successfully synthesized several structurally similar alkyl, alkenyl and alkynyl analogues, seven of which showed potential neuropreventive activity against MPP+-induced and CHP/TBHP oxidative stress induced neuroblastoma cell death.
Synthesis and characterization of achiral bent-core liquid crystalline molecules containing salicylaldimine-based with a wide temperature range of SmCP phase
Liao, Chien-Tung,Liu, Jung-Yo,Zou, Sing-Fang,Wu, Nien-Chieh,Wu, Zheng-Long,Lee, Jiunn-Yih
, p. 124 - 133 (2011/04/15)
The design and synthesis of a series bent-core materials base on a 3,4'-biphenyldiol central core containing salicylaldimine-based and two terminal tetradecyloxy tails are reported. In addition, the effects of lateral substituents (R = F and Cl) at the biphenyl core into 3'-position are examined. These substituents have a strong influence in reducing the clearing temperatures and increasing temperature range of SmCP phase. Upon cooling process the isotropic liquid, compound SB-Cl exhibits the lowest clearing transition temperature of 180 oC and the widest SmCP phase range of 129 °C. The mesophase behaviour were investigated by polarizing optical microscopy (POM), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and electro-optical (EO) measurements in the mesophase temperature range.
Novel photochromism of differently-linked bis-benzopyrans
Moorthy, Jarugu Narasimha,Venkatakrishnan, Parthasarathy,Samanta, Subhas
, p. 1354 - 1357 (2008/01/03)
The unique photochromic bis-chromene 5 incorporates the structural attributes of both 3 and 4. UV-vis irradiation of 5 leads to a dark brown colour, which is formed by mixing the purple and red colours observed for the photolysates of 3 and 4, respectively. The Royal Society of Chemistry.
ERbeta ligands. Part 1: the discovery of ERbeta selective ligands which embrace the 4-hydroxy-biphenyl template.
Edsall Jr., Richard J,Harris, Heather A,Manas, Eric S,Mewshaw, Richard E
, p. 3457 - 3474 (2007/10/03)
The synthesis and structure-activity relationships of a series of simple biphenyls is described. Optimization of the 4-hydroxy-biphenyl template led to compounds with ERbeta selectivity on the order of 20-70-fold.
Molecular design of nonchiral bent-core liquid crystals with antiferroelectric properties
Shen, Dong,Pegenau, Annegret,Diele, Siegmar,Wirth, Ina,Tschierske, Carsten
, p. 1593 - 1601 (2007/10/03)
Novel bent-core (banana-shaped) liquid crystals without Schiff-base units have been synthesized and investigated by polarized light optical microscopy, differential scanning calorimetry, X-ray scattering, and electrooptical investigations. These molecules are 4-(4- alkylbenzoyloxy)benzoates and 4-(4-alkoxybenzoyloxy)benzoates of resorcinol, 3,4'-dihydroxybiphenyl, and 4,4'-dihydroxy- 1,1':3', 1'-terphenyl. Three different mesophases were found depending on the molecular structure and the length of the terminal alkyl chains: a rectangular columnar phase, a highly ordered low-temperature mesophase, and an antiferroelectric switchable fluid smectic mesophase designated as SmCP(A). The influence of the molecular structure on the occurrence of the SmCP(A) phase was investigated. The spontaneous polarization of these molecules is quite high (P(s) = 500700 nC cm-2) and specially those molecules with long alkyl chains and short bent- core structures have low melting points and broad regions of this switchable mesophase. Furthermore, first examples of antiferroelectric switchable bent- core molecules with semifluorinated terminal chains will be described.
