- Cytochrome P450-catalyzed oxidation of N-benzyl-N-cyclopropylamine generates both cyclopropanone hydrate and 3-hydroxypropionaldehyde via hydrogen abstraction, not single electron transfer
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The suicide substrate activity of N-benzyl-N-cyclopropylamine (1) and N-benzyl-N-(1′-methylcyclopropyl)amine (2) toward cytochrome P450 and other enzymes has been explained by a mechanism involving single electron transfer (SET) oxidation, followed by rin
- Cerny, Matthew A.,Hanzlik, Robert P.
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Read Online
- Pd-Catalyst Containing a Hemilabile P,C-Hybrid Ligand in Amino Dicarbonylation of Aryl Halides for Synthesis of α-Ketoamides
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The amino dicarbonylation of aryl halides affording α-ketoamides with Pd catalysts is highly dependent on the stereoelectronic properties of the involved ligands. Ionic diphosphine ligand L4 can serve as precursor of a hemilabile P,C (phosphine, carbene)-hybrid ligand to form a stable Pd(II)-complex, Pd-L4. In contrast, analogues L1-L3 with a similar 1-(thiophen-3-yl)-benzimidazolyl skeleton behave as typical (mono/di)phosphines. The catalytic system resulting from the complexation of PdCl2(MeCN)2 and L4 exhibits good catalytic performance in terms of aryl iodides conversion (81-95%) and α-ketoamide selectivity (80-91%), as well as the available recyclability in the RTIL of [Bpy]BF4. The in situ FT-IR analysis reveals that the PdCl2(MeCN)2-L4 catalytic system favors the amino dicarbonylation toward α-ketoamides according to the proposed mechanism of cycle I, which involves two independent CO-insertion steps.
- Yang, Shu-Qing,Yao, Yin-Qing,Chen, Xiao-Chao,Lu, Yong,Zhao, Xiao-Li,Liu, Ye
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p. 1032 - 1041
(2021/05/07)
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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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- Pd-Catalyzed Oxidative Aminocarbonylation of Arylboronic Acids with Unreactive Tertiary Amines via C-N Bond Activation
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An efficient synthesis of tertiary amides from aryl boronic acids and inert tertiary amines through the oxidative carbonylation via C(sp3)-N bond activation is presented. This protocol significantly restricts the homocoupling biarylketone product. It involves the use of a homogeneous PdCl2/CuI catalyst and a heterogeneous Pd/C based catalyst, which promotes C(sp3)-N bond activation of tertiary amines with aryl boronic acids. This process represents a ligand-free, base-free, and recyclable catalyst along with an ideal oxidant like molecular oxygen.
- Kolekar, Yuvraj A.,Bhanage, Bhalchandra M.
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p. 14028 - 14035
(2021/05/29)
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- Organophotoredox-Mediated Amide Synthesis by Coupling Alcohol and Amine through Aerobic Oxidation of Alcohol
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The combination of an organic photocatalyst [4CzIPN (1,2,3,5-tetrakis(carbazol-9-yl)-4,6 dicyanobenzene) or 5MeOCzBN (2,3,4,5,6-pentakis(3,6-dimethoxy-9 H-carbazol-9-yl)benzonitrile)], quinuclidine, and tetra-n-butylammonium phosphate (hydrogen-bonding catalyst) was employed for amide bond formations. The hydrogen-bonded OH group activated the adjacent C?H bond of alcohols towards hydrogen atom transfer (HAT) by a radical species. The quinuclidinium radical cation, generated through single-electron oxidation of quinuclidine by the photocatalyst, employed to abstract a hydrogen atom from the α-C?H bond of alcohols selectively due to a polarity effect-produced α-hydroxyalkyl radical, which subsequently converted to the corresponding aldehyde under aerobic conditions. Then the coupling of the aldehyde and an amine formed a hemiaminal intermediate that upon photocatalytic oxidation produced the amide.
- Samanta, Samya,Shah, Sk. Sheriff,Shee, Maniklal,Singh, Amit Kumar,Singh, N. D. Pradeep,Venkatesh, Yarra
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- Supramolecular Pd(II) complex of DPPF and dithiolate: An efficient catalyst for amino and phenoxycarbonylation using Co2(CO)8 as sustainable C1 source
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Highly active, efficient and robust “dppf ligated tetranuclear palladium dithiolate complex” was synthesized and applied as a catalyst for chemical fixation of carbon monoxide for the synthesis value added chemicals such as tertiary amide and aromatic esters. The synthesized catalyst was characterized using different analytical techniques such as elemental analysis, 1H and 31P NMR spectroscopy. The use of Co2(CO)8 as a cheap, less toxic and low melting solid surrogate are additional advantages over the current protocol. The catalyst showed superior activity towards the Amino (10?3 mol % catalyst) and Phenoxycarbonylation (10-2 mol % catalyst) and high TON (104 to 103) and TOF (103 to 102 h-1). The Betol and Lintrin (active drug molecules) were synthesized under an optimized reaction condition. The scalability of the current protocol has been demonstrated up-to the gram level.
- Gaikwad, Vinayak V.,Mane, Pravin A.,Dey, Sandip,Patel, Divya,Bhanage, Bhalchandra M.
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- Design, synthesis and biological evaluation of novel 2-phenyl pyrimidine derivatives as potent Bruton's tyrosine kinase (BTK) inhibitors
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BTK is an effective target for the treatment of B-cell malignant tumors and autoimmune diseases. In this work, a series of 2-phenyl pyrimidine derivatives were prepared and their preliminary in vitro activities on B-cell leukemia cells as well as the BTK enzyme were determined. The results showed that compound 11g displayed the best inhibitory activity on BTK with an inhibition rate of 82.76% at 100 nM and excellent anti-proliferation activity on three B-cell leukemia lines (IC50 = 3.66 μM, 6.98 μM, and 5.39 μM against HL60, Raji and Ramos, respectively). Besides, the flow cytometry analysis results indicated that 11g inhibited the proliferation of the Raji cells in a dose- and time-dependent manner, and blocked the Ramos cells at the G0/G1 phase, which is in accordance with the positive control ibrutinib. The mechanism investigation demonstrated that 11g could inhibit the phosphorylation of BTK and its downstream substrate phospholipase γ2 (PLCγ2). All these results showed that 11g was a promising lead compound that merited further optimization as a novel class of BTK inhibitor for the treatment of B-cell lymphoblastic leukemia.
- Li, Xinyu,Shi, Binyu,Teng, Yu,Cheng, Yu,Yang, Huizhu,Li, Jiurong,Wang, Lianjian,He, Siying,You, Qidong,Xiang, Hua
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supporting information
p. 294 - 299
(2019/03/02)
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- Oxidative amidation of benzaldehyde using a quinone/DMSO system as the oxidizing agent
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An efficient transition-metal-based heterogeneous catalyst free procedure for obtaining the oxidative amidation of benzaldehyde using quinones as oxidizing agents in low molar proportions is described here. Pyrrolylquinones (PQ) proved to be more suitable
- Mejía-Farfán, Itzel,Solís-Hernández, Manuel,Navarro-Santos, Pedro,Contreras-Celedón, Claudia A.,Cortés-García, Carlos Jesus,Chacón-García, Luis
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p. 18265 - 18270
(2019/07/03)
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- Clickable coupling of carboxylic acids and amines at room temperature mediated by SO2F2: A significant breakthrough for the construction of amides and peptide linkages
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The construction of amide bonds and peptide linkages is one of the most fundamental transformations in all life processes and organic synthesis. The synthesis of structurally ubiquitous amide motifs is essential in the assembly of numerous important molecules such as peptides, proteins, alkaloids, pharmaceutical agents, polymers, ligands and agrochemicals. A method of SO2F2-mediated direct clickable coupling of carboxylic acids with amines was developed for the synthesis of a broad scope of amides in a simple, mild, highly efficient, robust and practical manner (>110 examples, >90% yields in most cases). The direct click reactions of acids and amines on a gram scale are also demonstrated using an extremely easy work-up and purification process of washing with 1 M aqueous HCl to provide the desired amides in greater than 99% purity and excellent yields.
- Wang, Shi-Meng,Zhao, Chuang,Zhang, Xu,Qin, Hua-Li
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p. 4087 - 4101
(2019/04/30)
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- Convenient metal-free direct oxidative amidation of aldehyde using dibromoisocyanuric acid under mild conditions
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A facile method for the direct synthesis of amides from aldehydes is described. Amide bonds were synthesized by an oxidative amidation in the presence of dibromoisocyanuric acid (DBI). Treatment of aromatic and aliphatic aldehydes with dibromoisocyanuric acid generated acyl bromide intermediates, which were employed to react with a variety of secondary and primary amines to give amides. Through this reaction method, various amides were synthesized directly from aldehydes under mild conditions in high yields and short times. This facile and efficient procedure provides potential strategy for the direct synthesis of amides from aldehydes.
- Kang, Soosung,La, Minh Thanh,Kim, Hee-Kwon
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supporting information
p. 3541 - 3546
(2018/08/29)
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- Direct Synthesis of Amides from Oxidative Coupling of Benzyl Alcohols and N-substituted Formamides Using a Co–Al Based Heterogeneous Catalyst
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Present work reports the direct synthesis of amides from oxidative coupling of benzyl alcohols with various N-substituted formamides using a cobalt-hydrotalcite (Co-HT) derived catalyst. The Co-HT derived catalysts (Co-HT-2, Co-HT-3 and Co-HT-4 having Co2+/Al3+ molar ratio in the catalyst preparation mixture as 1/1, 2/1 and 3/1 respectively) were prepare following a co-precipitation method and characterized well by powder XRD, XPS, FEG-SEM, EDS, DTG–TGA, FT-IR and N2 physisorption measurements. A range of functional amides were obtained in good yields from oxidative coupling of various substituted benzyl alcohols and a range of N-substituted formamides using Co-HT-3 catalyst and oxidant TBHP. Mechanistic investigation suggests that the amidation reaction is associated with the formation and coupling of radical species. Furthermore, the Co-HT derived catalyst was easily recoverable and recyclable with retained high catalytic activity towards the oxidative coupling of benzyl alcohol with DMF. Graphical Abstract: [Figure not available: see fulltext.].
- Subhedar, Dnyaneshwar D.,Gupta, Shyam Sunder R.,Bhanage, Bhalchandra M.
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p. 3102 - 3111
(2018/08/21)
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- Alternative formation of amides and β-enaminones from aroyl chlorides using the TiCl4-trialkylamine reagent system
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The TiCl4/NR3 reagent system has been successfully employed for the synthesis of amides and β-enaminones. The reaction of variously substituted benzoyl chlorides with the TiCl4/NR3 reagent system, by using two different experimental procedures (Method A and Method B), afforded alternatively the corresponding amides and β-enaminones as unique or major products. The two developed protocols were investigated with a series of tertiary amines. The reactions, modulated by the presence of TiCl4, provided the corresponding amides or β-enaminones with satisfactory yields. This paper reports a new method for carbon-carbon bond formation via the reaction of aroyl chlorides with the TiCl4/NR3 reagent system.
- Leggio, Antonella,Comandè, Alessandra,Belsito, Emilia Lucia,Greco, Marianna,Lo Feudo, Lucia,Liguori, Angelo
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p. 5677 - 5683
(2018/08/17)
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- 2-phenylpyrimidine compounds, preparation method and medical application
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The invention belongs to the field of medicines and particularly relates to 2-phenylpyrimidine compounds and pharmacologically-acceptable salts thereof and an isotope marker. The invention also discloses a pharmaceutical composition containing the substances and application of the pharmaceutical composition for treating diseases related with protein kinase activity, such as cancer and inflammation. (The formula is shown in the description).
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Paragraph 0062; 0063; 0064; 0065; 0066
(2018/06/15)
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- An Activatable Photosensitizer Targeted to γ-Glutamyltranspeptidase
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We adopted a spirocyclization-based strategy to design γ-glutamyl hydroxymethyl selenorhodamine green (gGlu-HMSeR) as a photo-inactive compound that would be specifically cleaved by the tumor-associated enzyme γ-glutamyltranspeptidase (GGT) to generate th
- Chiba, Mayumi,Ichikawa, Yuki,Kamiya, Mako,Komatsu, Toru,Ueno, Tasuku,Hanaoka, Kenjiro,Nagano, Tetsuo,Lange, Norbert,Urano, Yasuteru
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supporting information
p. 10418 - 10422
(2017/08/22)
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- Development of an azo-based photosensitizer activated under mild hypoxia for photodynamic therapy
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Photodynamic therapy (PDT) utilizes photoirradiation in the presence of photosensitizers to ablate cancer cells via generation of singlet oxygen (1O2), but it is important to minimize concomitant injury to normal tissues. One approac
- Piao, Wen,Hanaoka, Kenjiro,Fujisawa, Tomotsumi,Takeuchi, Satoshi,Komatsu, Toru,Ueno, Tasuku,Terai, Takuya,Tahara, Tahei,Nagano, Tetsuo,Urano, Yasuteru
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supporting information
p. 13713 - 13719
(2017/11/06)
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- HYDROGELS WITH BIODEGRADABLE CROSSLINKING
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Hydrogels that degrade under appropriate conditions of pH and temperature by virtue of crosslinking compounds that cleave through an elimination reaction are described. The hydrogels may be used for delivery of various agents, such as pharmaceuticals.
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Paragraph 0214-0215
(2017/11/16)
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- Sunlight assisted direct amide formation: Via a charge-transfer complex
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We report on the use of charge-transfer complexes between amines and carbon tetrachloride, as a novel way to activate the amine for photochemical reactions. This principle is demonstrated in a mild, transition metal free, visible light assisted, dealkylative amide formation from feedstock carboxylic acids and amines. The low absorption coefficient of the complex allows deep light penetration and thus scale up to a gram scale.
- Cohen, Irit,Mishra, Abhaya K.,Parvari, Galit,Edrei, Rachel,Dantus, Mauricio,Eichen, Yoav,Szpilman, Alex M.
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supporting information
p. 10128 - 10131
(2017/09/23)
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- Palladium supported on triphenylphosphine-functionalized porous organic polymer: An efficient heterogeneous catalyst for aminocarbonylation
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An efficient route for the catalytic synthesis of aryl amides via the aminocarbonylation of aryl iodides with amines is described using palladium supported on triphenylphosphine-functionalized porous organic polymer (Pd@KAPs(Ph-PPh3)) as the catalyst. Under low carbon monoxide pressure, the catalyst exhibited remarkable activity, and only 0.5 mol% palladium loading was required to achieve moderate to excellent yields (70-97 %) of aryl amides. The catalyst can be easily separated by a simple filtration process and recycled up to seven times with only minor loss of activity. The salient features of this protocol are the simplicity in handling of catalyst, low CO pressure, good functional group tolerance, high catalytic activity, negligible palladium leaching and effective catalyst recyclability.
- Lei, Yizhu,Zhang, Xuefeng,Gu, Yanlong,Hu, Jianglin,Li, Guangxing,Shi, Kaiyi
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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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p. 1781 - 1787
(2016/04/05)
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- Pd/C-catalyzed aminocarbonylation of aryl iodides via oxidative C-N bond activation of tertiary amines to tertiary amides
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This work reports oxidative N-dealkylation/carbonylation of tertiary amines to tertiary amides by using molecular oxygen as a sole oxidant using a Pd/C catalyst. This protocol is free from ligands, additives, bases, and cocatalysts. Different tertiary amines as well as aryl iodides have been examined for this transformation, providing desired products in good to excellent yield.
- Mane, Rajendra S.,Bhanage, Bhalchandra M.
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p. 1223 - 1228
(2016/02/18)
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- Acid anhydrides and the unexpected N,N-diethylamides derived from the reaction of carboxylic acids with Ph3P/I2/Et3N
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The formation of acid anhydrides from the phosphorous-mediated activation of carboxylic acids was investigated. Under various systems, activation of benzoic acid in the presence of base led to the formation of benzoic anhydride at different rates depending on the reactivity of the reagents. Using the Ph3P-I2/Et3N combination, most aryl acids were converted into the corresponding anhydrides in high yields within 5-10 min. However, for nitro-substituted derivatives, unexpectedly, N,N-diethylamides were isolated without anhydride formation. These results indicated the pronounced effect of substituents in governing these potential side reactions which can significantly affect the yields of acylation reactions promoted by phosphonium species.
- Phakhodee, Wong,Duangkamol, Chuthamat,Wangngae, Sirilak,Pattarawarapan, Mookda
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supporting information
p. 325 - 328
(2016/01/12)
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- SLOW-RELEASE CONJUGATES OF SN-38
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Conjugates of SN-38 that provide optimal drug release rates and minimize the formation of the corresponding glucuronate are described. The conjugates release SN-38 from a polyethylene glycol through a β-elimination mechanism.
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Paragraph 0058
(2015/04/22)
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- In situ protection and deprotection of amines for iron catalyzed oxidative amidation of aldehydes
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An environmentally friendly synthetic route by the application of CO2 to synthesize amides via in situ protection and deprotection of amines for iron catalyzed oxidative amidation of aldehydes was developed. Various secondary and tertiary amides have been synthesized in moderate to good yields under mild and neutral reaction conditions. The use of amine hydrochloride salts and hence base for neutralization step is totally avoided in this protocol.
- Bathini, Thulasiram,Rawat, Vikas S.,Bojja, Sreedhar
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supporting information
p. 5656 - 5660
(2015/09/15)
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- Catalyst-free amidation of aldehyde with amine under mild conditions
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A highly efficient, catalyst-free and one-pot procedure for the direct synthesis of amides from aldehydes and amines under mild conditions has been developed. Both aliphatic and aromatic aldehydes with primary or secondary amines are successfully converted to the corresponding amides, and it is observed that reactions can proceed in either aqueous or organic media.
- Yang, Hongyin,Hu, Wenjian,Deng, Shengjue,Wu, Tiantian,Cen, Haiman,Chen, Yiping,Zhang, Dela,Wang, Bo
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supporting information
p. 5912 - 5915
(2015/08/11)
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- Palladium-1,10-phenanthroline complex encaged in y zeolite: An efficient and highly recyclable heterogeneous catalyst for aminocarbonylation
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A promising route for catalytic synthesis of amides by aminocarbonylation of aryl iodides with amines is described using a palladium-1,10-phenanthroline complex encaged in Y zeolite. Complete conversions for aryl iodides and good to excellent yields (71-97%) of various amides were obtained at low Pd loadings of 0.6 mol%. The turnover frequency (TOF) could be up to 139 h-1. A satisfactory yield was obtained even after the catalyst was reused 16 times and the total turnover number (TON) for the 16 cycles was up to 2250. As evidenced by atomic absorption spectrophotometry, UV-vis spectroscopy and X-ray photoelectron spectroscopy, the palladium complex could well nestle down in the supercages of the zeolite without leaching during the recycling process. The significantly enhanced recyclability could be attributed to the double-protection strategy provided by the ligand and the zeolite structure for Pd0 species generated in situ within supercages preventing the migration and leaching of palladium. The supported catalyst has the advantages of easy handing, good to excellent yields, and outstanding recycling capacity for aminocarbonylation reactions of aryl iodides.
- Mei, Hui,Hu, Jianglin,Xiao, Se,Lei, Yizhu,Li, Guangxing
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- NHC-Pd complex-catalyzed double carbonylation of aryl iodides with secondary amines to α-keto amides
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A series of palladium-NHC compounds were prepared and their catalytic activity in the double carbonylation of aryl iodides to synthesize α-keto amides were examined. Palladium complexes bearing mixed NHC-phosphine exhibited high efficiency for the double carbonylation reaction. The effects of different solvents, base, temperature, carbon monoxide (CO), pressure, various amine and aryl iodides were investigated. Both electron-rich and electron-deficient aryl iodides afforded the corresponding substituted α-keto amides in moderate to good yields. A possible mechanism was also proposed. Copyright
- Zheng, Shuzhan,Wang, Yan,Zhang, Chunyan,Liu, Jianhua,Xia, Chungu
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- Direct amidation of carboxylic acids with tertiary amines: Amide formation over copper catalysts through C-N bond cleavage
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A copper-catalyzed system for the amidation of carboxylic acids with tert-amines through C-N bond cleavage was developed. This protocol is practical and represents a simple way to produce functionalized amides from basic starting materials in moderate to good yields. A plausible mechanism is proposed for the reaction. Copyright
- Xiong, Biquan,Zhu, Longzhi,Feng, Xiaofeng,Lei, Jian,Chen, Tieqiao,Zhou, Yongbo,Han, Li-Biao,Au, Chak-Tong,Yin, Shuang-Feng
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supporting information
p. 4244 - 4247
(2014/07/21)
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- Synthesis of N,N -diethylbenzamides via a nonclassical mitsunobu reaction
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The use of the Mitsunobu reaction for the synthesis of N,N- diethylbenzamides affords ortho-, meta-, and para-substituted benzamides containing both electron-donating and electron-withdrawing groups. While the preparation of numerous functional groups has
- Hoffman, J. Mason,Miller, Justin N.,Gardner, Margaret E.,Lepar, Danielle R.,Pongdee, Rongson
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supporting information
p. 976 - 980
(2014/03/21)
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- SULFONE LINKERS
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Sulfone linkers which couple drugs to carriers of various types are described. These linkers permit the release of the drug over time in a controlled manner. The release occurs through beta-elimination, and does not require enzymatic cleavage. Products of
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Paragraph 0084
(2013/03/26)
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- HYDROGELS WITH BIODEGRADABLE CROSSLINKING
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Hydrogels that degrade under appropriate conditions of pH and temperature by virtue of crosslinking compounds that cleave through an elimination reaction are described. The hydrogels may be used for delivery of various agents, such as pharmaceuticals. Thi
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Paragraph 0113
(2013/03/26)
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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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- CONTROLLED RELEASE FROM MACROMOLECULAR CONJUGATES
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The invention relates to conjugates of macromolecular carriers and drugs comprising linkers that release the drug or a prodrug through rate-controlled beta-elimination, and methods of making and using the conjugates.
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Page/Page column 44
(2011/11/30)
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- Aerobic oxidation of secondary benzylic alcohols and direct oxidative amidation of aryl aldehydes promoted by sodium hydride
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We reported herein new reactivities and possible mechanistic implications of a simplest oxidant (NaH/air) uncovered on a broad range of useful transformations, including aerobic alcohol oxidations, allylic alcohol isomerizations and oxidations, cyclopropyl alcohol fragmentations, and direct aryl aldehyde oxidative amidations. These readily implementable transition-metal-free processes feature exceptional material accessibility, operational simplicity, and environmental compatibility, and add new dimensions to its synthetic utilities that are fairly robust yet had not previously been fully realized and systematically explored.
- Wang, Xinbo,Wang, David Zhigang
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supporting information; experimental part
p. 3406 - 3411
(2011/06/17)
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- Efficient palladium-catalysed carbonylative and Suzuki-Miyaura cross-coupling reactions with bis(di-tert-butylphosphino)-o-xylene
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The use of the ligand bis(di-tert-butylphosphino)-o-xylene (dtbpx) in palladium-catalysed carbonylative and Suzuki-Miyaura cross-coupling reactions is described. Aryl and vinyl halides readily entered into the carbonylative catalytic cycle affording carboxylic acids, amides as well as primary, secondary and tertiary esters, respectively, in good yields. Aryl iodides, bromides and chlorides gave high yields of biphenyl products upon reaction with both activated and unactivated boronic acids.
- McNulty, James,Nair, Jerald J.,Sliwinski, Marcin,Robertson, Al J.
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scheme or table
p. 2342 - 2346
(2009/08/17)
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- A synthesis of sulfonamide analogs of platensimycin employing a palladium-mediated carbonylation strategy
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The monodentate ligand 1,3,5,7-tetramethyl-2,4,8-trioxa-6-phenyl-6-phospha-adamantane (PA-Ph) is shown to be highly effective in palladium-catalyzed carbonylative cross-coupling. Aryl and vinyl halides were efficiently converted to carboxylic acids, amides and to primary, secondary, and tertiary esters, respectively. Application of the Pd(OAc)2/PA-Ph (1:1) catalyst system proved critical in the methoxycarbonylation of a functionalized nitroresorcinol halide, allowing convenient access to novel platensimycin sulfonamide analogs.
- McNulty, James,Nair, Jerald J.,Capretta, Alfredo
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scheme or table
p. 4087 - 4091
(2009/12/01)
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- Efficient carbonylation reactions in phosphonium salt ionic liquids: Anionic effects
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(Formula Presented) Application of phosphonium salt ionic liquids in the carbonylation of aryl and vinyl halides is presented. Anionic effects were uncovered with the bromide ionic liquid emerging as the superior media. Acid bromide intermediates were detected in control experiments providing an extended view on the overall catalytic cycle involved. Solvent-free product isolation and recycling of the ionic liquid containing active Pd-catalyst are also demonstrated.
- McNulty, James,Nair, Jerald J.,Robertson, Al
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p. 4575 - 4578
(2008/03/12)
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- One pot direct synthesis of amides or oxazolines from carboxylic acids using Deoxo-Fluor reagent
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A mild and highly efficient one pot-one step condensation and/or condensation-cyclization of various acids to amides and/or oxazolines using Deoxo-Fluor reagents is described. Parallel syntheses of various free fatty acids with 2-amino-2,2-dimethyl-1-propanol resulted with excellent yields.
- Kangani, Cyrous O.,Kelley, David E.
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p. 8917 - 8920
(2007/10/03)
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- [Bis(2-methoxyethyl)amino]sulfur Trifluoride, the Deoxo-Fluor Reagent: Application toward One-Flask Transformations of Carboxylic Acids to Amides
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The use of the Deoxo-Fluor reagent is a versatile method for acyl fluoride generation and subsequent one-flask amide coupling. It provides mild conditions and facile purification of the desired products in good to excellent yields. We have explored the utility of this reagent for the one-flask conversion of acids to amides and Weinreb amides and as a peptide-coupling reagent.
- White, Jonathan M.,Tunoori, Ashok Rao,Turunen, Brandon J.,Georg, Gunda I.
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p. 2573 - 2576
(2007/10/03)
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- Double carbonylation of aryl iodides with diethylamine catalyzed by dinuclear palladium complexes
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Dinuclear palladium complexes bridged by a novel PNNP ligand, N,N ′-bis[(2-diphenylphosphino)phenylformamidinate (dpfam), were found to be very efficient and selective catalysts for the double carbonylation of iodobenzene with diethylamine using K3PO4 as base and 1,4-dioxane as solvent with a TON up to 105 and selectivity of 96%.
- Tsukada, Naofumi,Ohba, Yoichi,Inoue, Yoshio
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p. 436 - 443
(2007/10/03)
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- Conversion of thioamides into their corresponding oxygen analogues using silver carbonate supported on celite
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Silver carbonate supported on celite (Ag2CO3/Celite) is used as a mild heterogeneous reagent for conversion of a variety of thioamides into their corresponding amides in acetonitrile at room temperature.
- Movassagh,Lakouraj,Gholami
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p. 1507 - 1511
(2007/10/03)
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- Conversion of thioamides into their corresponding oxygen analogues using silver carbonate supported on celite
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Silver carbonate supported on celite (Ag2CO3/Celite) is used as a mild heterogeneous reagent for conversion of variety of thioamides into their corresponding amides in acetonitrile at room temperature.
- Movassagh,Lakouraj,Gholami
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p. 1943 - 1947
(2007/10/03)
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- A convenient method for the synthesis and one-pot reaction of acyl chlorides using a scavenging resin
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A simple, efficient and fast method for the preparation of acyl halides from fatty carboxylic acids using a solid phase scavenging approach is presented herein. The title compounds can then be isolated, used as a solution or react in one-pot to form esters and amides with good to excellent yields.
- Girard,Tranchant,Niore,Herscovici
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p. 1577 - 1580
(2007/10/03)
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- Caro's acid supported on silica gel. Part 2: Conversion of thioamides into amides
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A series of thioamide compounds have been converted into their corresponding amides under mild condition by treatment with Caro's acid supported on silica gel.
- Movassagh,Lakouraj,Ghodrati
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p. 2353 - 2358
(2007/10/03)
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- Ozone-mediated Nitration of Benzoic Acid, its Alkali and Alkali-earth Metal Salts, Ester, Acid Chloride, Nitrile and Amide with Nitrogen Dioxide
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The title compounds except for the amide are smoothly nitrated with nitrogen dioxide at low temperatures in the presence of ozone, giving a mixture of the corresponding nitro derivatives mainly composed of the meta isomer in high yield.The nitration products are generally rich in the ortho isomer compared with those obtained by the conventional procedures based on the use of nitric acid or mixed acid.Under similar conditions, benzamide readily loses nitrogen to afford benzoic acid and its nitro derivatives, while N,N-diethylbenzamide is converted into a mixture of three isomeric nitro derivatives with an approximate ratio ortho:meta:para = 3:3:4.
- Suzuki, Hitomi,Tomaru, Jun-ichiro,Murashima, Takashi
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p. 2413 - 2416
(2007/10/02)
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- PALLADIUM-CATALYZED SYNTHESIS OF AROMATIC ACID DERIVATIVES BY CARBONYLATION OF ARYL IODIDES AND Alk3SnNu (Nu = MeO, Et2N, PhS, EtS)
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Carbonylation of the ArI/Alk3SnNu system (Nu = MeO, Et2N), leading to esters and amides of substituted benzoic acids, occurs readily in the presence of phosphinepalladium complexes.When Nu = PhS and EtS either a cross-coupling product (Ar = p-NO2C6H4) or a carbonylation product (Ar = Ph) is formed predominantly, depending on the nature of ArI.Stoichiometric reactions of ArPdI(PPh3)2 with carbon monoxide, resulting in acylpalladium complexes, and reactions of ArCOPdI(PPh3)2 with Alk3SnNu have been studied.Some mechanistic aspects are discussed.
- Bumagin, N. A.,Gulevich, Yu. V.,Beletskaya, I. P.
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p. 415 - 418
(2007/10/02)
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- Reaction of Diazonium Salts with Transition Metals. 6. Preparation of Mixed Acid Anhydrides from Arenediazonium Salts and Sodium Carboxylates under Palladium(0) Catalysis
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The palladium(0)-catalyzed reaction of arenediazonium tetrafluoroborates with carbon monoxide and sodium carboxylates in acetonitrile at 25 deg C gave mixed acid anhydrides, ArCOOCOR (Ar = 3-Me-Ph, 4-Me-Ph, 2-MeO-Ph, 4-Br-Ph, 4-I-Ph, 3-NO2-Ph, 4-NO2-Ph, and Ph; R = H, Me, Et, t-Bu, and Ph) in good yields.Homoaromatic acid anhydrides, (ArCO)2O, were obtained by heating of ArCOOCOMe at 100-120 deg C under vacuum.ArCOOCO-t-Bu can be utilized to obtain the corresponding arenecarboxamides by the reaction with some amines.
- Kikukawa, Kiyoshi,Kono, Kiyoshi,Nagira, Kazuhiko,Wada, Fumio,Matsuda, Tsutomu
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p. 4413 - 4416
(2007/10/02)
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- INVESTIGATIONS ON N,N-DIALKYLBENZAMIDES BY NMR SPECTROSKOPY. PART II. A COMPARISON OF BARRIERS TO ROTATION ABOUT THE AMIDE C-N BOND IN PARA 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 para-substituted N,N-dimethyl- and N,N-diethylbenzamides have been compared.A method allowing the detection using standard measurement conditions of small differences between barriers to rotation has been proposed.It has been stated that the barriers to rotation in N,N-dimethylbenzamides are ca. 2 kJ/mole higher than those in the corresponding N,N-diethylbenzamides and that the differences ΔMe-Et are at least partially due to those in entropies of activation.It has been observed that ΔMe-Et increases with the increasing electron donating properties of the para substituent .The observed phenomena have been rationalized in terms of steric interactions in the ground state of rotation in the molecules under investigation.
- Gryf-Keller, Adam,Terpinski, Jacek,Zajaczkowska-Terpinska, Ewa
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p. 1465 - 1471
(2007/10/02)
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