- One-pot synthesis of a highly disperse core-shell CuO-alginate nanocomposite and the investigation of its antibacterial and catalytic properties
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In this study, sodium alginate was extracted from Sargassum algae, collected from coastal waters of Bushehr, Persian Gulf, Iran and used as a stabilizing and wrapping agent for CuO nanoparticles. The synthesized nanocomposite was characterized by some spectroscopic and microscopic techniques, such as IR, XRD, Uv-vis, BET, BJH, zeta potential, SEM, TEM, HR-TEM, and XPS. The antibacterial effects of the CuO-alginate nanocomposite against some bacteria, isolated from a burn wound, were evaluated. The results showed that this nanocomposite had better antibacterial effects than its components onPseudomonas aeruginosaATCC 27853,Staphylococcus aureusATCC 12600,Streptococcus pyogenesATCC 19615, andStaphylococcus epidermidisATCC 49461. Among these,Staphylococcus aureusATCC 12600 was the most sensitive one to this nanocomposite, with the lowest minimum inhibitory concentration (2.08 mg mL?1) observed. Moreover, the synthesized nanocomposite showed good catalytic activity in the oxidative coupling of carboxylic acids withN,N-dialkylformamides toward the synthesis of amides.
- Habibi, Hassan,Mansourinejhad, Sanam,Saberi, Dariush,Shadi, Ahmad
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p. 199 - 211
(2021/12/30)
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- CuO-decorated magnetite-reduced graphene oxide: a robust and promising heterogeneous catalyst for the oxidative amidation of methylarenes in waterviabenzylic sp3C-H activation
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A magnetite-reduced graphene oxide-supported CuO nanocomposite (rGO/Fe3O4-CuO) was preparedviaa facile chemical method and characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), UV-vis spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Brunauer-Emmett-Teller (BET) analysis, vibrating-sample magnetometry (VSM), and thermogravimetric (TG) analysis. The catalytic activity of the rGO/Fe3O4-CuO nanocomposite was probed in the direct oxidative amidation reaction of methylarenes with free amines. Various aromatic and aliphatic amides were prepared efficiently at room temperature from cheap raw chemicals usingtert-butyl hydroperoxide (TBHP) as a “green” oxidant and low-toxicity TBAI in water. This method combines the oxidation of methylarenes and amide bond formation into a single operation. Moreover, the synthesized nanocomposites can be separated from the reaction mixtures using an external magnet and reused in six consecutive runs without a noticeable decrease in the catalytic activity.
- Ebrahimi, Edris,Khalafi-Nezhad, Ali,Khalili, Dariush,Rousta, Marzieh
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p. 20007 - 20020
(2021/11/12)
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- Palladium-Catalyzed Aminocarbonylation of Aryl Halides with N,N-Dialkylformamide Acetals
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We developed a protocol for the palladium-catalyzed aminocarbonylation of aryl halides using less-toxic formamide acetals as bench-stable aminocarbonyl sources under neutral conditions. Various aryl (including heteroaryl) halides reacted with N,N-dialkylformamide acetals in the presence of a catalytic amount of tris(dibenzylideneacetone)dipalladium(0)-chloroform adduct and xantphos to give the corresponding aromatic carboxamides at 90–140 °C without any activating agents or bases in up to quantitative chemical yield. This protocol was applied to aryl bromides, aryl iodides, and trifluoromethanesulfonic acid, as well as to relatively less-reactive aryl chlorides. A wide range of functionalities on the aromatic ring of the substrates were tolerated under the aminocarbonylation conditions. The catalytic aminocarbonylation was used to prepare the insect repellent N,N-diethyl-3-methylbenzamide as well as a synthetic intermediate of the dihydrofolate reductase inhibitor triazinate.
- Hirata, Shuichi,Osako, Takao,Uozumi, Yasuhiro
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- Visible-Light Photoredox-Catalyzed Amidation of Benzylic Alcohols
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A new photocatalyzed route to amides from alcohols and amines mediated by visible light is presented. The reaction is carried out in ethyl acetate as a solvent. Ethyl acetate can be defined a green and bio-based solvent. The starting materials such as the energy source are easily available, stable, and inexpensive. The reaction has shown to be general and high yielding.
- Gaspa, Silvia,Farina, Andrea,Tilocca, Mariella,Porcheddu, Andrea,Pisano, Luisa,Carraro, Massimo,Azzena, Ugo,De Luca, Lidia
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p. 11679 - 11687
(2020/10/23)
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- Cobalt-catalysed C–H methylation for late-stage drug diversification
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The magic methyl effect is well acknowledged in medicinal chemistry, but despite its significance, accessing such analogues via derivatization at a late stage remains a pivotal challenge. In an effort to mitigate this major limitation, we here present a strategy for the cobalt-catalysed late-stage C–H methylation of structurally complex drug molecules. Enabling broad applicability, the transformation relies on a boron-based methyl source and takes advantage of inherently present functional groups to guide the C–H activation. The relative reactivity observed for distinct classes of functionalities were determined and the sensitivity of the transformation towards a panel of common functional motifs was tested under various reaction conditions. Without the need for prefunctionalization or postdeprotection, a diverse array of marketed drug molecules and natural products could be methylated in a predictable manner. Subsequent physicochemical and biological testing confirmed the magnitude with which this seemingly minor structural change can affect important drug properties. [Figure not available: see fulltext.]
- Ackermann, Lutz,Friis, Stig D.,Johansson, Magnus J.
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p. 511 - 519
(2020/06/05)
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- Selective Methylation of Amides, N-Heterocycles, Thiols, and Alcohols with Tetramethylammonium Fluoride
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We herein disclose the use of tetramethylammonium fluoride (TMAF) as a direct and selective methylating agent of a variety of amides, indoles, pyrroles, imidazoles, alcohols, and thiols. The method is characterized by operational simplicity, wide scope, and ease of purification. Our computational studies suggest a concerted methylation-deprotonation as the preferred reaction pathway.
- Cheng, Hong-Gang,Pu, Maoping,Kundu, Gourab,Schoenebeck, Franziska
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supporting information
p. 331 - 334
(2019/12/30)
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- Amidation reaction of carboxylic acid with formamide derivative using SO3?pyridine
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The amidation reaction of carboxylic acid derivatives was developed using sulfur trioxide pyridine complex (SO3?py) as a commercially available and easily handled oxidant. This method could be applied to the reaction of various aromatic and aliphatic carboxylic acids, including optically active ones, with formamide derivatives to afford the corresponding amides in good to high yields.
- Kawano, Shota,Saito, Kodai,Yamada, Tohru
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supporting information
p. 584 - 586
(2018/04/12)
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- Nickel-catalyzed aminocarbonylation of aryl halides using carbamoylsilane as an amide source
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The nickel-catalyzed aminocarbonylation of aryl halides using carbamoylsilane as an amide source is developed. The procedure can prepare both tertiary and secondary amides, and is applicable to various carbamoylsilanes and aryl halides containing differen
- Wen, Xue-Ping,Han, Yu-Ling,Chen, Jian-Xin
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p. 45107 - 45112
(2017/10/13)
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- Oxidative amidation of benzaldehydes and benzylamines with: N -substituted formamides over a Co/Al hydrotalcite-derived catalyst
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The present work describes a highly efficient synthetic strategy for amides via oxidative coupling of benzaldehydes or benzylamines with N-substituted formamides using a heterogeneous Co/Al hydrotalcite-derived catalyst in the presence of TBHP. A series of Co/Al hydrotalcite-derived catalysts (Cat-2, Cat-3, and Cat-4 with the Co2+/Al3+ molar ratio in the synthesis mixture as 1/1, 2/1 and 3/1) have been prepared by a simple co-precipitation method and characterized using powder XRD, XPS, FEG-SEM, EDS, FT-IR, DTG-TGA and N2 physical adsorption techniques. Among the as-prepared catalysts, Cat-3 exhibited excellent catalytic activity towards the direct amidation of benzaldehydes as well as benzylamines bearing various substituents into the corresponding amides at 100 °C using TBHP as an oxidant. The mechanistic investigation of the amidation reaction revealed that the reaction follows a radical pathway. Furthermore, the catalyst is easily separable and recyclable without considerable loss in catalytic activity.
- Gupta, Shyam Sunder R.,Nakhate, Akhil V.,Rasal, Kalidas B.,Deshmukh, Gunjan P.,Mannepalli, Lakshmi Kantam
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p. 15268 - 15276
(2017/12/15)
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- Metal-Free Amidation of Acids with Formamides and T3P
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A new, simple and metal-free method for the direct formation of dialkylamides from carboxylic acids employing N,N-dialkylformamides as amine source is described. The one-pot reaction is promoted by propylphosphonic anhydride (T3P) in the presence of 0.5 equivalents of HCl.
- Bannwart, Linda,Abele, Stefan,Tortoioli, Simone
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p. 2069 - 2078
(2016/07/06)
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- Palladium-Catalyzed Aminocarbonylation of Aryl Halides with 2,4,6-Trichloro-1,3,5-triazine/Formamide Mixed Reagent
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In this work, the mixture of formamide and 2,4,6-trichloro-1,3,5-triazine (cyanuric chloride or TCT) is introduced as a new amidating agent in Pd-catalyzed aminocarbonylation of aryl halides. In the presence of a catalytic amount of palladium and TCT/formamide reagent, a range of aryl halides (X = Cl, Br, I) were converted into amides efficiently in N,N-dimethylformamide at 120 °C. The 2,4,6-trichloro-1,3,5-triazine/formamide mixed reagent was found to be an efficient amidating agent in Pd-catalyzed aminocarbonylation of aryl halides. In the presence of this reagent and a catalytic amount of Pd, a range of amides were synthesized by using aryl halides.
- Iranpoor, Nasser,Panahi, Farhad,Roozbin, Fatemeh,Erfan, Soodabeh,Rahimi, Sajjad
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supporting information
p. 1781 - 1787
(2016/04/05)
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- Copper-catalyzed amide bond formation from formamides and carboxylic acids
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A highly efficient copper-catalyzed approach to form amide bonds from formamides and carboxylic acids was developed. This protocol shows broad substrate scopes and high yields in the presence of 1 mol% catalyst and 4.0 equiv. formamides.
- Liu, Hong-Qiang,Liu, Jun,Zhang, Yang-Hui,Shao, Chang-Dong,Yu, Jing-Xun
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- General and efficient oxidative amidation of benzyl alcohols with amines using diacetoxyiodobenzene and TBHP
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A facile oxidative coupling of alcohols and amines to construct amides was developed using DIB as a catalyst and aqueous tert-butyl hydroperoxide as an oxidant. Various secondary and tertiary amides were prepared in good yield utilizing inexpensive and readily available reagents under mild reaction condition. The reaction involved operational simplicity, metal free oxidation, and wide functional group tolerance as attractive features.
- Sutar, Yogesh B.,Bhagat, Saket B.,Telvekar, Vikas N.
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p. 6768 - 6771
(2016/02/03)
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- Easy access to amides through aldehydic C-H bond functionalization catalyzed by heterogeneous Co-based catalysts
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A novel synthesis strategy for amides by oxidative amidation of aldehydes is developed using a heterogeneous Co-based catalyst. The Co composite was prepared by simple pyrolysis of a Co-containing MOF, to obtain well-dispersed Co nanoparticles enclosed by carbonized organic ligands. The catalysts were characterized by powder X-ray diffraction (PXRD), N2 physical adsorption, atomic absorption spectroscopy (AAS), transmission electron microscopy (TEM), scanning electronic microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The small Co nanoparticles embedded in the N-doped carbons were highly dispersed with an average size of ca. 7 nm. The Co@C-N materials exhibited significantly enhanced catalytic activity in the oxidative amidation of aldehydes in comparison to those of commercial sources. A series of amides can be easily obtained in good to excellent yields. It was found that the reaction proceeded via radicals under mild conditions, and the carbonyl group in the amide product was from the aldehyde. Moreover, the catalyst could be easily separated by using an external magnetic field and reused several times without significant loss in catalytic efficiency under the investigated conditions. (Chemical Equation Presented).
- Bai, Cuihua,Yao, Xianfang,Li, Yingwei
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p. 884 - 891
(2015/02/19)
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- WCl6/DMF as a new reagent system for the phosphine-free Pd(0)-catalyzed aminocarbonylation of aryl halides
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WCl6 in dimethyl formamide (DMF) is introduced as a new reagent system for aminocarbonylation of aryl halides in the presence of PdCl2 as pre-catalyst without any phosphorous ligand. Aryl iodides, bromides as well as chlorides were efficiently converted to their corresponding N,N-dimethyl amides in good to high yields. In this protocol, WCl6/DMF is responsible for the generation of both Pd(0) catalyst as well as the formation of a Vilsmeier imminium type intermediate.
- Iranpoor, Nasser,Firouzabadi, Habib,Rizi, Zeinab Tavangar,Erfan, Soodabeh
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p. 43178 - 43182
(2015/02/19)
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- Copper-catalyzed formation of N,N-dimethyl benzamide from nitrile and DMF under an O2 atmosphere
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Amidation of nitrile with N,N-dimethylformamide (DMF) was catalyzed by Cu2O with 1,10-phenanthroline as a ligand under an oxygen atmosphere. A variety of N,N-dimethyl benzamides were obtained in yields up to 84%.
- Hu, Chenxu,Yan, Xufei,Zhou, Xiangge,Li, Zhengkai
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p. 8179 - 8182
(2013/12/04)
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- Direct amidation of alcohols with N-substituted formamides under transition-metal-free conditions
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Go tandem! The first example of the direct amidation of alcohols with N-substituted formamides has been developed. A series of tertiary amides, including the challenging N,N-dimethyl-substituted amides, were obtained in moderate to good yields under transition-metal-free conditions (see scheme). TBHP=tert-butyl hydroperoxide. Copyright
- Xu, Kun,Hu, Yanbin,Zhang, Sheng,Zha, Zhenggen,Wang, Zhiyong
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supporting information; experimental part
p. 9793 - 9797
(2012/09/05)
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- Facile preparation of aromatic esters from aromatic bromides with ethyl formate or DMF and molecular iodine via aryllithium
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Various aromatic bromides were treated with n-BuLi and subsequently with ethyl formate, followed by the reaction with ethanol and molecular iodine in the presence of K2CO3 to provide the corresponding aromatic ethyl esters in good yields. Moreover, aromatic bromides could be transformed into the corresponding aromatic methyl esters in good yields by the treatment with n-BuLi and subsequently with DMF, followed by the reaction with methanol, molecular iodine, and K2CO3. Some aromatics could be also converted into the corresponding aromatic esters in good yields by the treatment with n-BuLi, and subsequently with ethyl formate or DMF, followed by the reaction with molecular iodine and K2CO3. The present reactions offer a novel route for the transition-metal-free, carbon-monoxide-free, and therefore environmentally benign one-pot conversion of aromatic bromides and aromatics into aromatic esters.
- Ushijima, Sousuke,Moriyama, Katsuhiko,Togo, Hideo
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experimental part
p. 4701 - 4709
(2012/07/28)
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- Cross coupling of acyl and aminyl radicals: Direct synthesis of amides catalyzed by Bu4NI with TBHP as an oxidant
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A radical solution: A Bu4NI/tert-butyl hydroperoxide (TBHP) catalyzed synthesis of amides through a cross-coupling reaction between acyl and aminyl radicals is described. This method involves the combination of aldehyde C-H bond functionalization and decarbonylation of N,N-disubstituted formamides (see scheme). The cross-coupling is metal-free, has a wide substrate scope, operational simplicity, and gives high yields on scale-up. Copyright
- Liu, Zhaojun,Zhang, Jie,Chen, Shulin,Shi, Erbo,Xu, Yuan,Wan, Xiaobing
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experimental part
p. 3231 - 3235
(2012/05/05)
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- Silicadiphenyl phosphinite (SDPP)/Pd(0) nanocatalyst for efficient aminocarbonylation of aryl halides with POCl3 and DMF
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Silicadiphenyl phosphinite (SDPP) as a new phosphorylated silica and catalytic amounts of Pd(II) generates nano SDPP/Pd(0) catalyst for the efficient aminocarbonylation of aryl halides in the presence of POCl3 and N,N-dimethylformamide (DMF). Amides are obtained in high yields from aryl iodides and also activated aryl bromides, chlorides.
- Iranpoor, Nasser,Firouzabadi, Habib,Motevalli, Somayeh
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experimental part
p. 69 - 74
(2012/03/09)
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- Pd/C: an efficient, heterogeneous and reusable catalyst for carbon monoxide-free aminocarbonylation of aryl iodides
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Carbon monoxide-free aminocarbonylation is carried out efficiently via coupling of N,N-dimethylformamide (DMF) with aryl iodides using Pd/C as a heterogeneous catalyst. The catalyst exhibits remarkable activity and is reusable for up to three consecutive cycles. The reaction is applicable to a wide variety of substituted aryl iodides with different steric and electronic properties providing excellent yields of the corresponding tertiary amides.
- Tambade, Pawan J.,Patil, Yogesh P.,Bhanushali, Mayur J.,Bhanage, Bhalchandra M.
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p. 2221 - 2224
(2008/09/18)
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- Aminocarbonylation of aryl halides using a nickel phosphite catalytic system
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(Formula Presented) The nickel and phosphite catalytic system with sodium methoxide enables a very efficient aminocarbonylation reaction to be performed between aryl iodides or bromides and N,N-dimethylformamide (DMF). Phosphite ligand 1, which is very st
- Ju, Jinhun,Jeong, Miso,Moon, Jeongju,Hyun, Min Jung,Lee, Sunwoo
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p. 4615 - 4618
(2008/03/13)
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- Atroposelectivity of reactions of benzylic metalated thiobenzamides and thionaphthamides
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N,N-Dialkyl-2-methylbenzenecarbothioamides and naphthalenecarbothioamides were prepared by thionation of amides with Lawesson's reagent under unusual conditions. Their axial chirality was evidenced. Benzylic deprotonation of thioamides bearing N,N-diisopr
- Ach, David,Reboul, Vincent,Metzner, Patrick
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p. 3398 - 3406
(2007/10/03)
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- Carbon monoxide free aminocarbonylation of aryl and alkenyl iodides using DMF as an amide source
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(figure presented) R = aryl or alkenyl Palladium-catalyzed coupling reaction of N,N-dimethylformamide with aryl or alkenyl halides successfully proceeded in the presence of phosphoryl chloride to afford the corresponding tertiary amides in good yields.
- Hosoi, Kazushi,Nozaki, Kyoko,Hiyama, Tamejiro
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p. 2849 - 2851
(2007/10/03)
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- A direct and mild conversion of tertiary aryl amides to methyl esters using trimethyloxonium tetrafluoroborate: A very useful complement to directed metalation reactions
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The scope and generality of a direct process for the conversion of tertiary amides directly to methyl esters has been investigated. The process involves a two-step, one pot procedure in which a tertiary amide is first treated with trimethyloxonium tetrafluoroborate to generate an imidate intermediate which is then hydrolyzed, generally by the addition of saturated aqueous sodium bicarbonate solution. Although this process fails for aliphatic amides, very good yields are realized for a variety of amides derived from aromatic carboxylic acids. Steric hindrance at the N-alkyl group is well tolerated; thus N,N-dimethyl, -diethyl, and -diisopropyl amides can all be utilized successfully. (C) 2000 Elsevier Science Ltd.
- Keck, Gary E,McLaws, Mark D,Wager, Travis T
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p. 9875 - 9883
(2007/10/03)
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- 1(2H)-isoquinolinones and 1-isoquinolineamines as cancer chemotherapeutic agents
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3-(1-Naphthalenyl)-1(2H)-isoquinolinones and 3-(1-naphthalenyl)-1-isoquinolineamines are useful as cancer chemotherapeutic agents.
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- INVESTIGATIONS ON N,N-DIALKYLBENZAMIDES BY NMR SPECTROSCOPY. PART IV. COMPARISON OF BARRIERS TO ROTATION ABOUT THE AMINE C-N BOND IN ORTHO-SUBSTITUTED N,N-DIMETHYL-AND N,N-DIETHYLBENZAMIDES
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The barriers to rotation about the amide C-N bond in a series of ortho-substituted N,N-dimethyl and N,N-diethylbenzamides have been compared.It has been stated that for most of substituents, namely CH3, Cl, Br, I and NO2, the rates of rotation in both series of compounds are identical within the accuracy of measurement (kEt/kMe ca.1).The remaining compounds (F, CN, CH3) show a higher rate of rotation in the series of diethylbenzamides (kEt/kMe ca.1,5).An exception are the OH derivatives in which the internal H-bond is present and because of that the barrier to rotation is lowered and the kEt/kMe ratio raised up to 2.3.
- Gryf-Keller, Adam,Terpinski, Jacek,Zajaczkowska-Terpinska, Ewa
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p. 429 - 434
(2007/10/02)
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- The mechanism of electrochemical reduction of N-haloamides in acetonitrile: trapping of intermediate amide anions and father-son protonation
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The electrochemical reduction of N-haloamides (ZCONRX) in acetonitrile involves two consecutive one-electron transfers and generates the amide anions.Attempts to trap the intermediate amidyl radical resulting from first electron transfer were unssuccesful.In the case of the N-halo-N-hydroamides (R=H), the amide anion formed at the electrode abstracts a proton from an incoming N-halo-N-hydroamide molecule to give the parent amide and the conjugate base of the N-haloamide (father-son protonation).Thus, half of the N-halo-N-hydroamide reaching the electrode is reduced, the other half being converted to its conjugate base.In acetonitrile-LiClO4 (0.2 M) containing 0.2percent water, the conjugate base is reducible and polarograms therefore show two waves (irreversible and diffusion controlled) of equivalent intensities due respectively to the reduction of the N-halo-N-hydroamide and to the reduction of its conjugate base.In the case of the N-chloro-N-alkyl(aryl)amides (X=Cl, R=alkyl or aryl), the amide anion abstracts a proton from the medium to give the parent amide and anionic species that react with the starting N-chloroamide regenerating the amide anion.Hence, the coulometric results are low (0.5 F/mol).However, in the presence of acetic acid, the reduction consumes 2 F/mol as expected.The N-alkylamide anion has been trapped by N-alkylation and N-acylation.The voltammograms of N-chloro-N-alkyl(aryl)amides show multiple waves on mercury and platinum due to passivation-adsorption phenomena but a single wave on vitreous carbon.
- Berube, Denis,Lessard, Jean
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p. 1127 - 1142
(2007/10/02)
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