摘要：
A novel palladium-catalyzed coupling reaction of an aryl methyl ketone with two molecules of an aryl halide to yield symmetric diarylmethanes is described. In the facile one-pot reaction, the aryl methyl ketone acts as a formal methylene donor. The experimental facts, including TLC monitoring, speculated intermediates as the raw materials, analysis of the cesium benzoate coproduct by ex situ IR spectroscopy, and the cross-coupling reactions of two different aryl halides, indicate a mechanism involving a palladium-catalyzed sequential two-step coupling process, in which the presence of a trace amount of H2O is indispensable. The reaction is applicable to a broad spectrum of substrates and delivers the products in good to excellent yields. Access to unsymmetrical diarylmethanes with this method is also explored and various factors are discussed.
期刊：
Journal of Colloid and Interface Science,2014年421:49-55 ISSN：0021-9797
通讯作者：
Deng, Hongtao
作者机构：
[Zhang, Aidong; Deng, Hongtao; Yang, Can; Zheng, Fei; Yang, Yunyan; Li, Xia] Cent China Normal Univ, Coll Chem, Wuhan 430079, Peoples R China.;[Zhao, Xinjun] South Cent Univ Nationalities, Coll Chem & Mat Sci, Wuhan 430074, Peoples R China.
通讯机构：
[Deng, Hongtao] C;Cent China Normal Univ, Coll Chem, Wuhan 430079, Peoples R China.
关键词：
High adhesion;Nanofibrous membrane;Polyurethane;Superhydrophobicity
摘要：
The fluorination of hyperbranched polyurethane (HPU) was achieved by atom transfer radical grafting polymerization (ATRgP) of dodecafluoroheptyl methacrylate that was initiated from 2-bromoisobutyryl bromide-modified end groups of HPU. The nanofibrous membrane of fluorinated HPU was prepared by electrospinning. The structure of fluorinated HPU was characterized by Fourier-transform infrared spectroscopy (FTIR) and H-1 nuclear magnetic resonance spectrum (H-1 NMR). The surface of nanofibrous membrane was investigated with scanning electron microscope (SEM), atomic force microscope (AFM), X-ray photoelectron spectroscopy (XPS) and water contact angle (WCA) analysis, respectively. The results suggested that compared with the reported linear fluorine-containing polyurethane materials, rather high fluorine content up to 29.14% was achieved on the surface of fluorinated HPU nanofibrous membrane. Meanwhile, a superhydrophobic surface (WCA 159.7 degrees) with high adhesion to water was successfully fabricated via a convenient electrospinning process. The prepared material is promising for the application in microfluidic devices.(c) 2014 Elsevier Inc. All rights reserved.
摘要：
Two 5-pyrimidinyl-1, 2, 4-oxadiazoles were synthesized through two different routes and their structures were characterized by single-crystal X-ray diffraction, NMR and MS. Compound 3, 5-(2-chloro-4-methyl-6-phenylpyrimidin-5-yl)-3-phenyl-1, 2, 4-oxadiazole, crystallizes in orthorhombic, space group Pbca with a = 19.1575(11), b = 8.2115(5), c = 21.2035(12) Å, V = 3335.6(3) Å3 and Z = 4. Compound 6, 5-(2, 6-dichloropyrimidin-4-yl)-3-phenyl-1, 2, 4-oxadiazole, crystallizes in monoclinic space group Pn with a = 8.4275(13), b = 5.4088(8), c = 13.493(2) Å, β = 99.768(3)°, V = 4658.6(6) Å3 and Z = 8. Preliminary bioassay indicated that the two title compounds had good herbicidal activities.
期刊：
JOURNAL OF ORGANIC CHEMISTRY,2014年79(14):6554-6562 ISSN：0022-3263
通讯作者：
Tu, Hai-Yang
作者机构：
[Zhang, Ai-Dong; Liu, Fu-Di; Wang, Xing; Tu, Hai-Yang] Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol, Minist Educ, Wuhan 430079, Peoples R China.
通讯机构：
[Tu, Hai-Yang] C;Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol, Minist Educ, Wuhan 430079, Peoples R China.
摘要：
A one-pot palladium-catalyzed synthesis of symmetrical and unsymmetrical diarylmethanones using acetophenone and aryl bromides as raw materials has been developed. In this reaction, acetophenone acts as a latent carbonyl donor and two pathways of palladium-catalyzed sequential coupling and aerobic oxidation are identified. The reaction is applicable to a spectrum of substrates and delivers the products in moderate to good yields. This method can be used for the synthesis of ketoprofen, a nonsteroidal anti-inflammatory drug, in a two-step procedure and 45% overall yield.
作者：
Zhi-Hua Yu;Hu-Fei Zheng;Wei Yuan;Ai-Dong Zhang（张爱东）;De-Qing Shi
作者机构：
[Ai-Dong Zhang; Zhi-Hua Yu; Hu-Fei Zheng; Wei Yuan; De-Qing Shi] Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Central China Normal University,Wuhan, 430079
作者机构：
[Zhang,Aidong; Lei,Hui; Tu,Haiyang] Key Laboratory of Pesticide & Chemical Biology Ministry of Education College of Chemistry Central China Normal University,Wuhan 430079
摘要：
Auxin is an essential plant hormone. Indole-3-acetic acid（IAA） is the principal natural auxin in higher plants. Auxin antagonists can mimic the effects of natural auxin and affect auxin responses. In spite of decades of research, the mechanisms of auxin action have proved difficult to elucidate. Thus, detecting the auxin receptors may discover the sites of action of auxin/auxin antagonists, which may provide new opportunities in researching the mode of action. In recent research, it was reported that some specific TIR1 antagonists were synthesized by introducing different alkyl chains in the α-position of IAA. When the chain was hexyl, the IAA molecule abolished auxin activity and exhibited excellent inhibitory activity in Arabidopsis[1]. We synthesized N-methoxycarbonylmethyl-indole-3-acetic acid methyl ester（3） from indole-3-acetic acid, then introduced a series of aliphatic and polar PEG linkers in the α-position of IAA to generate specific auxin signaling probes（5） that can be used to dissect auxin signal transduction. It was noted that the end of the linkers must be Boc-protected amines. Subsequently, Boc-deprotection liberated the primary amino group（6） that was used to couple Fluorescein isothiocyanate to detect the pathways or targets protein that these molecules might bind to[2]. Our experiment indicated that the introduction of hexyl or PEG linker made the IAA possess antiauxin activity. What’s more, these molecules equipped with the PEG linkers have better antiauxin activity than those with aliphatic linkers. Additionally, fluorescence microscope was used to detect the pathways of these molecules. Our work not only demonstrated an example of a specific small-molecule auxin antagonist probes, but also detected the pathways of these molecules and the approximate location of the target protein which these molecules might bind to. It may be a supplementary method to study the mechanism of auxin.
