- New Syntheses of 3-Indolylglyoxal
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In a study of the possibilities of a simple method for the preparation of 3-indolylglyoxals two new methods for the synthesis of indolylglyoxal structures were proposed.The first method consists in oxidation of 3-hydroxyacetylindole with the dimethyl sulfoxide - oxalyl chloride complex, but for a number of reasons it is virtually inapplicable to the preparation of substituted indolylglyoxals.In the second case the readily synthesized 3-indolylglyoxyl chlorides are reduced to the corresponding aldehydes in good yields by means of trialkyltin hydrides.
- Vereshchagin, A. L.,Bryanskii, O. V.,Semenov, A. A.
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- Room-temperature copper-catalyzed electrophilic amination of arylcadmium iodides with ketoximes
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We started our study by preparation two ketoximes. Later, there were studies to reveal these ketoximes' effects in the electrophilic amination reaction with organocadmium reagents. Primarily, it was observed that arylcadmium iodides could not be reacted with ketoximes at room temperature in the absence of a catalyst. CuCN was a suitable catalyst for this electrophilic amination reaction of arylcadmium iodides and allowed the preparation of functionalized aniline derivatives in good yields under mild reaction conditions. We obtained the results indicated that the yield of primary arylamines was strongly dependent on the steric and electronic effects of organocadmium reagent and amination agent. In the case of both amination reagents, meta-substituted arylamines were obtained in higher yields than para-substituted arylamines. We observed that acetone O-(4-chlorophenylsulfonyl)oxime, 1, as an aminating agent, was more successful than acetone O-(2-Naphthylsulfonyl)oxime, 2, in the synthesis of functionalized arylamines by electrophilic amination of corresponding aryl cadmium iodides. In this method, there is no cadmium release to the environment.
- Korkmaz, Adem
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p. 3119 - 3125
(2021/05/10)
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- Selective Carbon-Carbon Bond Amination with Redox-Active Aminating Reagents: A Direct Approach to Anilines?
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Amines are among the most fundamental motifs in chemical synthesis, and the introduction of amine building blocks via selective C—C bond cleavage allows the construction of nitrogen compounds from simple hydrocarbons through direct skeleton modification. Herein, we report a novel method for the preparation of anilines from alkylarenes via Schmidt-type rearrangement using redox-active amination reagents, which are easily prepared from hydroxylamine. Primary amines and secondary amines were prepared from corresponding alkylarenes or benzyl alcohols under mild conditions. Good compatibility and valuable applications of the transformation were also displayed.
- Qiu, Xu,Wang, Yachong,Su, Lingyu,Jin, Rui,Song, Song,Qin, Qixue,Li, Junhua,Zong, Baoning,Jiao, Ning
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p. 3011 - 3016
(2021/09/13)
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- Chemoselective reduction of nitroarenes with hydrazine over a highly active alumina-supported cobalt nanocatalyst
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A green and efficient procedure is reported for the chemoselective reduction of nitroarenes catalyzed by a highly active alumina-supported cobalt nanocatalyst in the presence of hydrazine hydrate. The nanocatalyst can be applied under mild reflux conditions for the synthesis of arlyamines in high yields. Moreover, the catalyst can be easily recovered by simple filtration and reused several times without obvious loss in its catalytic activity.
- Albadi, Jalal,Samimi, Heshmat Allah,Jalali, Mehdi
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p. 740 - 744
(2019/10/14)
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- Preparation and Characterization of an Efficient Nano-Inorganic Composite of CuO/ZnO/Al2O3 for the Catalytic Amination of Aryl Halides in Aqueous Conditions
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In this research, an efficient recyclable nano-inorganic composite of CuO/ZnO/Al2O3 (CuO/ZnO/Al2O3 nanocatalyst) is prepared, characterized and used for the amination of aryl halides with aqueous ammonia in water. The catalyst was prepared by co-precipitation method and characterized by various techniques such as the X-ray diffraction, scanning electron microscope, energy dispersive spectroscopy, and brunauer–Emmett–Teller surface area analysis. Various aryl halides reacted with aqueous ammonia and corresponding products were obtained in high yields. CuO/ZnO/Al2O3 nanocatalyst as an efficient stable catalyst is recyclable up to five consecutive runs by simple filtration. Graphical Abstract: An efficient recyclable nano-inorganic composite of CuO/ZnO/Al2O3 (CuO/ZnO-Al2O3 nanocatalyst) is prepared, characterized and used for the amination of aryl halides with aqueous ammonia in water. [Figure not available: see fulltext.].
- albadi, Jalal,Jalali, Mehdi,Samimi, Heshmat Allah
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p. 3750 - 3756
(2018/10/15)
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- A circulating aqueous phase system method of synthesizing aromatic primary amine
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The invention discloses a method for synthesizing an aromatic primary amine in a circulating water phase system. According to the method, an aryl halide and ammonia water are taken as raw materials, water is taken as a solvent, a carbonate, a fluoride, a phosphate or a hydroxide of an alkali metal or an alkaline-earth metal or a compound which can be converted to a corresponding alkali in water is taken as the alkali, polyamine carboxylic acid and a salt type compound thereof are taken as ligands, and a copper source catalyst is adopted for catalyzing the formation of the aromatic primary amine from the aryl halide and the ammonia water. According to the method disclosed by the invention, the water is used as the solvent, any phase transfer of the catalyst is not required, and the catalyst, the ligands and the reaction solvent, namely the water, can be recycled, so that the environment-friendly property of reaction is effectively improved, the method is more in line with requirements of green chemical development, a substrate particularly has a wide range of applications, and the method further has broad prospects in the aspects of preparation of natural products, medicaments and pesticides.
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Paragraph 0043; 0044
(2016/10/20)
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- Synthesis and biological evaluation of 3-alkyl-1,5-diaryl-1H-pyrazoles as rigid analogues of combretastatin A-4 with potent antiproliferative activity
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A series of novel 3-alkyl-1,5-diaryl-1H-pyrazoles were synthesized as combretastatin A-4 (CA-4) analogues and evaluated for antiproliferative activity against three human cancer cell lines (SGC-7901, A549 and HT-1080). Most of the target compounds displayed moderate to potent antiproliferative activity, and 7k was found to be the most potent compound. Structure-activity relationships indicated that compounds with a trimethoxyphenyl A-ring at the N-1 position of the pyrazole skeleton were more potent than those with the A-ring at the C-5 position. Tubulin polymerization and immunostaining experiments revealed that 7k potently inhibited tubulin polymerization and disrupted tubulin microtubule dynamics in a manner similar to CA-4. Computational modelling demonstrated that the binding of 7k to the colchicine binding site on microtubules may involve a similar mode as CA-4.
- Xu, Qile,Qi, Huan,Sun, Maolin,Zuo, Daiying,Jiang, Xuewei,Wen, Zhiyong,Wang, Zhiwei,Wu, Yingliang,Zhang, Weige
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- Transition-metal-free access to primary anilines from boronic acids and a common +NH2 equivalent
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Diversely substituted anilines are prepared by treatment of functionalized arylboronic acids with a common, inexpensive source of electrophilic nitrogen (H2N-OSO3H, HSA) under basic aqueous conditions. Electron-rich substrates are found to be the most reactive by this method. However, even moderately electron-poor substrates are well tolerated under the room temperature conditions. Sterically hindered substrates appear to be equally effective compared to unhindered ones. Highly electron-deficient substrates afford product in very low yields at room temperature, but moderate to good yields are obtained at refluxing temperatures. Our method is also amenable to electrophilic amination of several common boronic acid derivatives (e.g., pinacol esters). We demonstrate that it can be combined with metal-halogen exchange reactions or a variety of directed ortho metalation protocols in a "one-pot" sequence for the synthesis of aromatic amines with unique substitution patterns. DFT studies, in combination with experimental results, suggest that the reaction occurs via base-mediated activation of HSA, followed by 1,2 aryl B-N migration. This mode of activation appears to be critical for the success of the reaction and allows, for the first time, a general, electrophilic amination of boronic acids at ambient temperature.
- Voth, Samantha,Hollett, Joshua W.,Mccubbin, J. Adam
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p. 2545 - 2553
(2015/03/18)
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- Supramolecular assembly of isocyanorhodium(i) complexes: An interplay of rhodium(i)···rhodium(i) interactions, hydrophobic-hydrophobic interactions, and host-guest chemistry
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A series of tetrakis(isocyano)rhodium(I) complexes with different chain lengths of alkyl substituents has been found to exhibit a strong tendency toward solution state aggregation upon altering the concentration, temperature and solvent composition. Temperature- and solvent-dependent UV-vis absorption studies have been performed, and the data have been analyzed using the aggregation model to elucidate the growth mechanism. The aggregation is found to involve extensive Rh(I)···Rh(I) interactions that are synergistically assisted by hydrophobic-hydrophobic interactions to give a rainbow array of solution aggregate colors. It is noted that the presence of three long alkyl substituents is crucial for the observed cooperativity in the aggregation. Molecular assemblies in the form of nanoplates and nanovesicles have been observed in the hexane-dichloromethane solvent mixtures, arising from the different formation mechanisms based on the alkyl chain length of the complexes. Benzo-15-crown-5 moieties have been incorporated for selective potassium ion binding to induce dimer formation and drastic color changes, rendering the system as potential colorimetric and luminescent cation sensors and as building blocks for ion-controlled supramolecular assembly.
- Chan, Alan Kwun-Wa,Wong, Keith Man-Chung,Yam, Vivian Wing-Wah
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p. 6920 - 6931
(2015/06/16)
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- A simple and recyclable copper/DTPA catalyst system for amination of aryl halides with aqueous ammonia in water
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Commercially available CuO/DTPA (diethylenetriaminepentaacetic acid) was established to be a low-cost, recyclable, and environmentally benign homogeneous catalyst system for direct amination of aryl halides with ammonia. Primary aryl amines can be readily prepared from both electron-withdrawing and electron-donating aryl halides in good yields in water without the addition of surfactants.
- Yang, Bo,Liao, Lihao,Zeng, Yongheng,Zhu, Xinhai,Wan, Yiqian
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p. 100 - 103
(2014/01/06)
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- Green recyclable CuO-CeO2 nanocomposite catalyzed amination of aryl halides with aqueous ammonia in water
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CuO-CeO2 nanocomposite as a green recyclable catalyst, catalyzed amination of aryl halides with aqueous ammonia in water. This catalyst can be easily recovered by simple filtration and recycled up to 5 consecutive runs with consistent activity. The procedure provides some advantages such as simple work-up, clean procedure, relatively short reaction times and high yields of the products. Efficient procedure for the amination of aryl halides catalyzed by Cu-CeO2 nanocomposite. Copyright
- Albadi, Jalal,Mansournezhad, Azam
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p. 396 - 398
(2014/06/10)
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- Introducing catalytic lossen rearrangements: Sustainable access to carbamates and amines
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A new, highly efficient and environmentally benign catalytic variant of the Lossen rearrangement is described. Dimethyl carbonate (DMC) as green activation reagent of hydroxamic acids in presence of catalytic amounts of tertiary amine bases {1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), 1,8-biazabicyclo 5.4.0 undec-7-ene (DBU), 1,4-diazabicyclo[2.2.2]octane (DABCO), and triethylamine} and small quantities of methanol initiate the rearrangement. Methyl carbamates were obtained in good to moderate yields when aliphatic hydroxamic acids were employed in this catalytic Lossen rearrangement; under the same conditions aromatic hydroxamic acids yielded anilines. Notably, the mixture of DMC/methanol was recycled several times without observing decreased yields, thus minimizing the produced waste. Moreover, several other organic carbonates were successfully employed in the introduced catalytic Lossen rearrangement procedure. Copyright
- Kreye, Oliver,Wald, Sarah,Meier, Michael A. R.
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- 2,4-DIAMINO-6,7-DIHYDRO-5H-PYRROLO[2,3]PYRIMIDINE DERIVATIVES AS FAK/Pyk2 INHIBITORS
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The invention relates to a novel class of 2,4-diamino-6,7-dihydro-5H-pyrrolo[2,3]pyrimidine derivatives as a FAK and/or Pyk2 inhibitor, to a process for their preparation, and to a composition thereof, as well as to use of the compounds for the inhibiting FAK and/or Pyk2 and method for the treatment of a FAK and/ or Pyk2 mediated disorder or disease.
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- Amination of aryl halides by using an environmentally benign, recyclable copper catalyst
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The combination of CuSO4 with naturally occurring sucrose in a biodegradable aqueous solution of PEG-200 has been confirmed as a novel, recyclable, and environmentally benign homogeneous catalyst system for the direct amination of aryl halides with NH3·H2O. Electron-rich, electron-poor, and even ortho-substituted aryl bromides and iodides could be aminated to provide the desired primary arylamines in high yields at 90 °C without the need of an inert atmosphere. The combination of CuSO4 with naturally occurring sucrose in a biodegradable, aqueous solution of PEG-200 has been confirmed to be a novel, recyclable, and environmentally benign homogeneous catalyst system for the direct amination of aryl halides with NH3·H2O. Copyright
- Huang, Manna,Wang, Leilei,Zhu, Xinhai,Mao, Zuxing,Kuang, Daizhi,Wan, Yiqian
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supporting information
p. 4897 - 4901
(2013/01/14)
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- Preparation of two sets of 5,6,7-trioxygenated dihydroflavonol derivatives as free radical scavengers and neuronal cell protectors to oxidative damage
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An unusual class of 5,6,7-trioxygenated dihydroflavonols (3a-e and 4a-j) were designed and prepared. Their antioxidative properties were assessed by examining their capacities in several in vitro models, including superoxide anion and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, rat liver homogenate lipid peroxidation inhibition, PC12 cells protection from oxidative damage, and xanthine oxidase inhibition. These dihydroflavonols displayed positive quenching abilities towards O2{radical dot} - and DPPH free radicals, in which the majority exhibited superior antioxidant properties to Vitamin C. cis-Configurated compound (±)-3e demonstrated remarkable inhibition to LPO with an IC50 value of 1.9 ± 0.3 μM, which was apparently stronger than that of quercetin (IC50 = 6.0 ± 0.4 μM). trans-Configurated dihydroflavonol (±)-4h exhibited significant protective effect on PC12 cells against oxidative damage with an EC50 value of 41.5 ± 5.3 μM, more effective compared to that of quercetin (EC50 = 81.8 ± 8.7 μM). The 6-OH-5,7-dimethoxy analogue (±)-3d showed significant inhibition of xanthine oxidase with an IC50 value of 16.0 ± 0.8 μM, which is superior to that of allopurinol (IC50 = 23.5 ± 2.0 μM). In addition to the hypothesized action mechanism of the bio-active compounds, 3D modeling was used to analyze the relationship between the minimized-energy structures and antioxidant activities.
- Gong, Jingxu,Huang, Kexin,Wang, Feng,Yang, Leixiang,Feng, Yubing,Li, Haibo,Li, Xiaokun,Zeng, Su,Wu, Xiumei,Stoeckigt, Joachim,Zhao, Yu,Qu, Jia
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supporting information; experimental part
p. 3414 - 3425
(2009/09/27)
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- Novel palladium-on-carbon/diphenyl sulfide complex for chemoselective hydrogenation: Preparation, characterization, and application
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A diphenyl sulfide immobilized on palladium-on-carbon system, Pd/C[Ph 2S], was developed to achieve the highly chemoselective hydrogenation of alkenes, acetylenes, azides, and nitro groups in the presence of aromatic ketones, halides, benzyl esters, and N-Cbz protective groups. Instrumental analyses of the heterogeneous catalyst demonstrated that diphenylsul fide was embedded on Pd/C via coordination of its sulfur atom to palladium metal or physical interaction with graphite layers of the activated carbon. The catalyst could be recovered and reused at least five times without any significant loss of the reactivity.
- Mori, Akinori,Mizusaki, Tomoteru,Kawase, Masami,Maegawa, Tomohiro,Monguchi, Yasunari,Takao, Shinobu,Takagi, Yukio,Sajikia, Hironao
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experimental part
p. 406 - 410
(2009/04/06)
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- 4′-Alkoxyl substitution enhancing the anti-mitotic effect of 5-(3′,4′,5′-substituted)anilino-4-hydroxy-8-nitroquinazolines as a novel class of anti-microtubule agents
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Mitosis inhibitors are powerful anticancer drugs. Based on a novel anti-microtubule agent of 5-(4′-methoxy)anilino-4-hydroxy-8-nitroquinazoline, a series of 5-(3′,4′,5′-substituted)anilino-4-hydroxy-8- nitroquinazolines were designed and synthesized to investigate the effect of the substitution on the inhibitory activity against mitotic progression of tumor cells. The large alkoxyl substitution on the 4′-position of 5-anilino ring is beneficial for the potency. The 5-(3′,4′,5′-trimethoxy)anilino-8-nitroquinazoline (1h) displays an overwhelming activity in arresting the cells at the G2/M phase, providing a promising new template for further development of potent microtubule-targeted anti-mitotic drugs.
- Jin, Yi,Zhou, Zu-Yu,Tian, Wei,Yu, Qiang,Long, Ya-Qiu
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p. 5864 - 5869
(2007/10/03)
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- Chemoselective hydrogenation method catalyzed by Pd/C using diphenylsulfide as a reasonable catalyst poison
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While Pd/C is one of the most useful catalysts for hydrogenation, the high catalyst activity of Pd/C causes difficulty in its application to chemoselective hydrogenation between different types of reducible functionalities. In order to achieve chemoselective hydrogenation using Pd/C, we investigated catalyst poison as a controller of the catalyst activity. We found that the addition of Ph2S (diphenylsulfide) to the Pd/C-catalyzed hydrogenation reaction mixture led to reasonable deactivation of Pd/C. By the use of the Pd/C-Ph2S catalytic system, olefins, acetylenes, and azides can be selectively reduced in the coexistence of aromatic carbonyls, aromatic halides, cyano groups, benzyl esters, and N-Cbz (benzyloxycarbonyl) protecting groups. The present method is promising as a general and practical chemoselective hydrogenation process in synthetic organic chemistry.
- Mori, Akinori,Mizusaki, Tomoteru,Miyakawa, Yumi,Ohashi, Eri,Haga, Tomoko,Maegawa, Tomohiro,Monguchi, Yasunari,Sajiki, Hironao
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p. 11925 - 11932
(2007/10/03)
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- A mild deprotection of trichloroethyl carbamates using indium metal
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The trichloroethoxycarbonyl moiety was efficiently removed from carbamates to furnish the corresponding amines using indium metal in good to excellent yields.
- Mineno, Tomoko,Choi, Seoung-Ryoung,Avery, Mitchell A.
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p. 883 - 886
(2007/10/03)
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- MCM-silylamine Pd(II)complex: A heterogeneous catalyst for selective azide reductions
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Palladium complex immobilized on MCM-41 catalyses the reduction of alkyl, aryl and arylsulfonyl azides to the corresponding amines in excellent yields under mild conditions.
- Kantam, M. Lakshmi,Chowdari, N. Srcenivasa,Rahman, Ateeq,Choudary
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p. 1413 - 1414
(2007/10/03)
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- Constituents of Eupomatia Species. VII. Dienone-Phenol and Dienol-Benzene Rearrangements in the Eupodienone-1 Series
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Rearrangement of eupodienone-1 and derivatives, including certain dienols, under a variety of acidic conditions produced dibenzocyclooctene derivatives.Spectroscopic evidence and chemical degradation showed that in the rearrangements alkyl rather than aryl group migration had occured.The stereochemistry of the products is discussed.
- Bowden, Bruce F.,Read, Roger W.,Taylor, Walter C.
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p. 799 - 817
(2007/10/02)
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- The Kinetics of the Reactions of Picryl Chloride with Some Substituted Anilines. Part 6. 4-Substituted and 3,4-Disubstituted Anilines
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Arrhenius parameters have been measured for the reactions of picryl chloride with the following substituted anilines in acetonitrile: 4-X- (X = F, Cl, Br, I, Me, or OMe); 3,4-X2- (X = Cl, Br, Me, or OMe); 4-X-3-nitro- (X = F, Cl, or Me); 3-X-4-methoxy- (X = F, Cl, Br, or I); 3-fluoro-4-nitro-; and 3,4,5-trimethoxy-aniline.In the 3,4-disubstituted series the effect of two methyl groups on the free energy of activation is strictly additive, but for the rest the measured rate constants are greater than those calculated on the assumption of additivity.The results are rationalized in terms of the positions of the transition state on the reaction co-ordinate.
- Emokpae, Thomas A.,Eguavoen, Osa,Khalil-Ur-Rahman,Hirst, Jack
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p. 832 - 834
(2007/10/02)
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