- Efficient and accessible silane-mediated direct amide coupling of carboxylic acids and amines
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A straightforward method for the direct synthesis of amides from amines and carboxylic acids without exclusion of air or moisture using diphenylsilane with N-methylpyrrolidine has been developed. Various amides are made efficiently, and broad functional group compatibility is shown through a Glorius robustness study. A gram-scale synthesis demonstrates the scalability of this method. This journal is
- D'Amaral, Melissa C.,Jamkhou, Nick,Adler, Marc J.
-
supporting information
p. 288 - 295
(2021/01/28)
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- Ammonia-borane as a Catalyst for the Direct Amidation of Carboxylic Acids
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Ammonia-borane serves as an efficient substoichiometric (10%) precatalyst for the direct amidation of both aromatic and aliphatic carboxylic acids. In situ generation of amine-boranes precedes the amidation and, unlike the amidation with stoichiometric amine-boranes, this process is facile with 1 equiv of the acid. This methodology has high functional group tolerance and chromatography-free purification but is not amenable for esterification. The latter feature has been exploited to prepare hydroxyl- and thiol-containing amides.
- Ramachandran, P. Veeraraghavan,Hamann, Henry J.
-
supporting information
p. 2938 - 2942
(2021/05/04)
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- Copper(II) mediated C-8 amination of 1-naphthylamide derivatives with acyclic and cyclic amines
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A simple and facile copper(II) mediated protocol for C-8 amination of 1-naphthylamide derivatives is reported here. Picolinamide and its derivatives were used as a bidentate directing group for the C-8 amination reaction. Various substituted naphthylamide derivatives with numerous cyclic and acyclic amines proceed in good yields under mild conditions. Air was used solely as an oxidant.
- Sahoo, Tapan,Sarkar, Souvik,Ghosh, Subhash Chandra
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supporting information
(2021/02/20)
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- Synthetic method for preparing amide compounds through co-catalysis of niobium pentachloride and ionic liquid
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The invention relates to a synthetic method for preparing amide compounds through co-catalysis of niobium pentachloride and ionic liquid. The preparation method is characterized by comprising the following steps: weighing organic carboxylic acid, organic amine, niobium pentachloride, ionic liquid and a molecular sieve, adding the materials into a reactor, adding an organic solvent, and reacting for 6-24 hours at the reaction temperature of 70-110 DEG C to obtain a corresponding amide product. The molar ratio of the organic carboxylic acid to the organic amine to the niobium pentachloride to the ionic liquid is 1:(1-3):(0.01-1):(0.05-1); wherein the mass ratio of the organic carboxylic acid to the molecular sieve is 1: (0.2-1). According to the method, the substrate range is expanded, the reaction yield is high (95% or above), the catalyst dosage is small, the atom economy is high, the catalyst is cheap and easy to obtain, the production cost can be greatly reduced, and the method is suitable for industrial production.
- -
-
Paragraph 0041-0043
(2020/07/13)
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- Tris(o-phenylenedioxy)cyclotriphosphazene as a Promoter for the Formation of Amide Bonds between Aromatic Acids and Amines
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The atom-efficient formation of amide bonds has emerged as a top-priority research field in organic synthesis, as amide bonds constitute the backbones of proteins and represent an important structural motif in drug molecules. Currently, the increasing demand for novel discoveries in this field has focused substantial attention on this challenging subject. Herein, the degradable 1,3,5-triazo-2,4,6-triphosphorine (TAP) motif is presented as a new condensation system for the dehydrative formation of amide bonds between diverse combinations of aromatic carboxylic acids and amines. The underlying reaction mechanism was investigated, and potential catalyst intermediates were characterized using 31 P NMR spectroscopy and ESI mass spectrometry.
- Movahed, Farzaneh Soleymani,Sawant, Dinesh N.,Bagal, Dattatraya B.,Saito, Susumu
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p. 3253 - 3262
(2020/11/02)
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- Oxidative C-H/N-H Annulation of Aromatic Amides with Dialkyl Malonates: Access to Isoindolinones and Dihydrobenzoindoles
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A copper-mediated oxidative C-H/N-H annulation of aromatic amides with dialkyl malonates has been presented to afford synthetically valuable dihydrobenzoindoles and isoindolinones. The reaction proceeds through direct oxidative C(sp2)-H/C(sp3)-H coupling followed by an intramolecular N-H/C(sp3)-H dehydrogenative coupling to deliver the target motifs with broad scope and functional group tolerance.
- Pradhan, Sourav,Roy, Subhasish,Banerjee, Sonbidya,De, Pinaki Bhusan,Punniyamurthy, Tharmalingam
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p. 5741 - 5749
(2020/05/19)
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- Solvent-free iron(III) chloride-catalyzed direct amidation of esters
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Amide functional groups are prominent in a broad range of organic compounds with diverse beneficial applications. In this work, we report the synthesis of these functional groups via an iron(iii) chloride-catalyzed direct amidation of esters. The reactions are conducted under solvent-free conditions and found to be compatible with a range of amine and ester substrates generating the desired amides in short reaction times and good to excellent yields at a catalyst loading of 15 mol%.
- Mkhonazi, Blessing D.,Shandu, Malibongwe,Tshinavhe, Ronewa,Simelane, Sandile B.,Moshapo, Paseka T.
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supporting information
(2020/03/17)
-
- Graphene oxide: A convenient metal-free carbocatalyst for facilitating amidation of esters with amines
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Herein, we report a graphene oxide (GO) catalyzed condensation of non-activated esters and amines, that can enable diverse amides to be synthesized from abundant ethyl esters forming only volatile alcohol as a by-product. GO accelerates ester to amide conversion in the absence of any additives, unlike other catalysts. A wide range of ester and amine substrates are screened to yield the respective amides in good to excellent yields. The improved catalytic activity can be ascribed to the oxygenated functionalities present on the graphene oxide surface which forms H-bonding with the reactants accelerating the reaction. Improved yields and a wide range of functional group tolerance are some of the important features of the developed protocol.
- Patel, Khushbu P.,Gayakwad, Eknath M.,Shankarling, Ganapati S.
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p. 2661 - 2668
(2020/02/20)
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- Rhodium-Catalyzed Copper-Assisted Intermolecular Domino C?H Annulation of 1,3-Diynes with Picolinamides: Access to Pentacyclic π-Extended Systems
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A new mode of reactivity of 1,3-diynes in rhodium-catalyzed oxidative annulation reactions has enabled the rapid assembly of extended π systems from readily available picolinamide derivatives. The process involves a double C?H bond activation and the iterative annulation of two 1,3-diyne units, with each alkyne moiety engaged in an orchestrated insertion sequence with high regiocontrol, leading to the formation of five new C?C bonds and the construction of four fused rings in a single operation. Either isoquinoline-1-carboxamides or fused polycyclic systems can be accessed by a switch in the regioselectivity of the second diyne insertion depending on the reaction conditions. DFT theoretical calculations have elucidated that the cooperative participation of both rhodium and copper in substrate activation, favored in the presence of excess of the copper(II) salt, is key to such a reversal of regioselectivity and subsequent multiple cyclization leading to fused polycyclic products. The role of copper was found to be essential in assisting both multiple insertion and rhodium-walking sequences, with the implication of intermediates with a Rh?Cu bond (2.60 ?).
- Martínez, ángel Manu,Alonso, Inés,Rodríguez, Nuria,Gómez Arrayás, Ramón,Carretero, Juan C.
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supporting information
p. 5733 - 5742
(2019/04/03)
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- Rh-Catalyzed Annulative Insertion of Terminal Olefin onto Pyridines via a C-H Activation Strategy Using Ethenesulfonyl Fluoride as Ethylene Provider
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A Rh(III)-catalyzed annulative insertion of ethylene onto picolinamides was achieved, providing a portal to a class of unique pyridine-containing molecules bearing a terminal olefin moiety for diversification. Application of this method for modification of Sorafenib was also accomplished.
- Li, Chen,Qin, Hua-Li
-
supporting information
p. 4495 - 4499
(2019/06/27)
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- Pd(II)-Catalyzed Direct Sulfonylation of Benzylamines Using Sodium Sulfinates
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A Pd(II)-catalyzed direct sulfonylation of benzylamines with sodium sulfinates using a removable bidentate directing group is illustrated. The transformation is highly regioselective and tolerates wide functional groups. The mechanistic study reveals that radical species are involved in this reaction. This method delivers a direct synthetic strategy to obtain highly functionalized sulfonylated benzylamines.
- Karmakar, Ujjwal,Samanta, Rajarshi
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p. 2850 - 2861
(2019/03/29)
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- [Cp*RhIII] in an Ionic Liquid as a Highly Efficient and Recyclable Catalytic Medium for Regio- and Diastereoselective Csp3–H Carbenoid Insertion
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Reported herein is a bidentate-assisted Csp3–H bond insertion using Cp*RhIII/IL as a highly efficient and recyclable catalytic medium, while showing good functional group tolerance. Notably, the application of ionic liquid not only lowered the temperature, but also enhanced the diastereoselectivity of this reaction. This work significantly expanded the scope of ionic liquids in Csp3–H functionalizations.
- Li, Jianglian,Zhou, Lin,Wang, Yaoling,Ma, Qiang,Lei, Yuan,Lai, Ruizhi,Luo, Yi,Hai, Li,Wu, Yong
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supporting information
p. 7448 - 7451
(2019/11/28)
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- Highly chemoselective, sterically sensitive NHC-catalysed amine acylation with pyridil
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A new strategy for the protection of amines has been developed involving reaction with pyridil under the influence of N-heterocyclic carbene catalysis. The methodology is capable of distinguishing between two amines characterised by small differences in steric bulk and the resulting pyridoyl amides can be cleaved without requiring either strongly acidic or basic hydrolysis.
- Maguire, Amy C.,Kumar, Vikas,Connon, Stephen J.
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supporting information
p. 13526 - 13529
(2019/11/14)
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- Graphene Oxide: A Metal-Free Carbocatalyst for the Synthesis of Diverse Amides under Solvent-Free Conditions
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An environmentally friendly, inexpensive, carbocatalyst, graphene oxide (GO) promoted efficient, metal-free transamidation of various carboxamides with aliphatic, cyclic, and aromatic amines is demonstrated. The protocol is equally applicable to phthalimide, urea, and thioamide determining its adaptability. The oxygenated functionalities such as carbonyl (?C=O), epoxy (?O?), carboxyl (?COOH) and hydroxyl (?OH), present on graphene oxide surface impart acidic properties to the catalyst. The graphene oxide being heterogeneous in nature, work efficiently under solvent-free reaction conditions providing desired products in good to excellent yields. The one-pot synthesis of 2,3-Dihydro-5H-benzo[b]-1,4-thiazepin-4-one moiety by GO catalyzed Aza Michael addition followed by intramolecular transamidation is also described. A plausible reaction mechanistic pathway involving H-bonding is discussed. The graphene oxide can be recycled and reused up to five cycles without much loss in catalytic activity. (Figure presented.).
- Patel, Khushbu P.,Gayakwad, Eknath M.,Patil, Vilas V.,Shankarling, Ganapati S.
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supporting information
p. 2107 - 2116
(2019/03/26)
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- Manganese/cobalt-catalyzed oxidative C(sp3)-H/C(sp3)-H coupling: A route to α-tertiary β-arylethylamines
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Reported herein is an oxidative coupling reaction of an α-C(sp3)-H bond of amine with a benzylic C(sp3)-H bond through Mn or Co catalysis to provide diverse collections of α-tertiary β-arylethylamines. This protocol features an easily installed and removable coordinating activation group, a wide scope of substrates, low-cost metal catalysts, easily available starting materials and synthetic simplicity.
- Tan, Meiling,Li, Kaizhi,Yin, Jiangliang,You, Jingsong
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supporting information
p. 1221 - 1224
(2018/02/09)
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- Chelation-promoted Efficient C?H/N?H Cross Dehydrogenative Coupling between Picolinamides and Simple Ethers under Copper Catalysis
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A highly efficient copper-catalyzed C?H/N?H cross dehydrogenative coupling between picolinamides and simple ethers was developed. The reaction was promoted by the chelation assistance of removable picolinyl group and exhibited excellent TON and TOF number. This method was applicable to both N-aryl and alkyl picolinamides as well as various cyclic and acyclic ethers with good functional group compatibility. It also possessed the merit of air and moisture tolerance and easy operation. (Figure presented.).
- Yue, Qiang,Xiao, Zhen,Kuang, Zhengkun,Su, Zhengding,Zhang, Qian,Li, Dong
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supporting information
p. 1193 - 1198
(2018/02/06)
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- Diboron-Catalyzed Dehydrative Amidation of Aromatic Carboxylic Acids with Amines
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Tetrakis(dimethylamido)diboron and tetrahydroxydiboron are herein reported as new catalysts for the synthesis of aryl amides by catalytic condensation of aromatic carboxylic acids with amines. The developed protocol is both simple and highly efficient over a broad range of substrates. This method thus represents an attractive approach for the use of diboron catalysts in the synthesis of amides without having to resort to stoichiometric or additional dehydrating agents.
- Sawant, Dinesh N.,Bagal, Dattatraya B.,Ogawa, Saeko,Selvam, Kaliyamoorthy,Saito, Susumu
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supporting information
p. 4397 - 4400
(2018/08/09)
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- Poly(methylhydrosiloxane) as a green reducing agent in organophosphorus-catalysed amide bond formation
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Development of catalytic amide bond formation reactions has been the subject of the intensive investigations in the past decade. Herein we report an efficient organophosphorus-catalysed amidation reaction between unactivated carboxylic acids and amines. Poly(methylhydrosiloxane), a waste product of the silicon industry, is used as an inexpensive and green reducing agent for in situ reduction of phosphine oxide to phosphine. The reported method enables the synthesis of a wide range of secondary and tertiary amides in very good to excellent yields.
- Hamstra, Daan F. J.,Lenstra, Danny C.,Koenders, Tjeu J.,Rutjes, Floris P. J. T.,Mecinovi?, Jasmin
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supporting information
p. 6426 - 6432
(2017/08/10)
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- Cobalt-Catalyzed ortho-C?H Functionalization/Alkyne Annulation of Benzylamine Derivatives: Access to Dihydroisoquinolines
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A practical picolinamide-directed C?H functionalization/alkyne annulation of benzylamine derivatives enabling access to the previously elusive 1,4-dihydroisoquinoline skeleton was developed using molecular O2 as the sole oxidant and Co(OAc)2 as precatalyst. The method is compatible with both internal and terminal alkynes and shows high versatility and functional-group tolerance. Furthermore, full preservation of enantiopurity is observed when using non-racemic α-substituted benzylamine derivatives. Kinetic analysis of the reagents and catalyst, labeling experiments, and the isolation and identification of catalytically competent Co-complexes revealed important insights about the mechanism.
- Martínez, ángel Manu,Rodríguez, Nuria,Gómez-Arrayás, Ramón,Carretero, Juan C.
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supporting information
p. 11669 - 11676
(2017/08/30)
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- Cobalt-Catalyzed Selective Synthesis of Isoquinolines Using Picolinamide as a Traceless Directing Group
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Picolinamide has first been employed as a traceless directing group for the cobalt-catalyzed oxidative annulation of benzylamides with alkynes to synthesize isoquinolines through C-H/N-H bonds activation. Oxygen is used as a terminal oxidant. This protocol exhibits good functional group tolerance and excellent regioselectivity. Both terminal and internal alkynes can be efficiently applied to this catalytic system as substrates.
- Kuai, Changsheng,Wang, Lianhui,Li, Bobin,Yang, Zhenhui,Cui, Xiuling
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supporting information
p. 2102 - 2105
(2017/04/27)
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- A comparative study of amide-bond forming reagents in aqueous media – Substrate scope and reagent compatibility
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A survey of amidation reagents demonstrating DIC-HOPO, DMT-MM, COMU-collidine, TPTU-NMI, EEDQ, CDI and EDC-Oxyma to be effective for the coupling of carboxylic acids with amines in the presence of water and the absence of problematic dipolar aprotic solvents is reported. DMT-MM was shown to provide the best yields for the coupling of a secondary amine, TPTU-NMI and COMU-collidine for aniline, whilst the combination of DIC with HOPO afforded the broadest substrate scope and the highest yields for a sterically demanding carboxylic acid.
- Badland, Matthew,Crook, Robert,Delayre, Bastien,Fussell, Steven J.,Gladwell, Iain,Hawksworth, Michael,Howard, Roger M.,Walton, Robert,Weisenburger, Gerald A.
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supporting information
p. 4391 - 4394
(2017/10/20)
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- Ruthenium(II) complexes encompassing 2-oxo-1,2-dihydroquinoline-3-carbaldehyde thiosemicarbazone hybrid ligand: A new versatile potential catalyst for dehydrogenative amide synthesis
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Ruthenium(II) complexes (1–6) supported by a series of 2-oxo-1,2-dihydroquinoline-3-carbaldehyde substituted thiosemicarbazone ligands [2-oxo-1,2-dihydroquinoline-3-carbaldehyde thiosemicarbazone (L1), 2-oxo-1,2-dihydroquinoline-3-carbaldehyde N-methyl thiosemicarbazone (L2), 2-oxo-1,2-dihydroquinoline-3-carbaldehyde N-phenylthiosemicarbazone (L3)] have been synthesized and structurally characterized by analytical, spectroscopic methods and X-ray crystallographic technique. The studies revealed that the ligands act as mononegative tridentate in ruthenium(II) complexes and a distorted octahedral geometry has been proposed for the complexes. In addition, the complexes have been found to catalyze the amidation of alcohols with amines in the presence of KtBuO–toluene system. The catalyst 3 displayed higher activity in substrates, including phenyl-, pyridine-, furan-, and thiophene-substituted alcohols with primary and secondary amines. The protocol is highly attractive because of easily available starting materials, high atom efficiency and environmental friendliness.
- Selvamurugan, Sellappan,Ramachandran, Rangasamy,Prakash, Govindan,Nirmala, Muthukumaran,Viswanathamurthi, Periasamy,Fujiwara, Shoji,Endo, Akira
-
-
- Transamidation of carboxamides with amines over nanosized zeolite beta under solvent-free conditions
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A highly efficient approach to transamidation of carboxamides with amines over nanosized zeolite beta under solvent-free conditions has been successfully demonstrated. Transamidation of a variety of amides with amines produced the respective N-alkyl amides in moderate to excellent yields.
- Durgaiah, Chevella,Naresh, Mameda,Swamy, Peraka,Srujana, Kodumuri,Rammurthy, Banothu,Narender, Nama
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-
- Ruthenium(II) carbonyl complexes containing bidentate 2-oxo-1,2-dihydroquinoline-3-carbaldehyde hydrazone ligands as efficient catalysts for catalytic amidation reaction
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The coordination behavior of 2-oxo-1,2-dihydroquinoline-3-carbaldehyde hydrazone ligands in ruthenium(II) and the catalytic activity of newly synthesized complexes have been studied. The complexes [RuCl(CO)(PPh3)2(L1)] (1), [RuCl(CO)(AsPh3)2(L1)] (2), [RuCl(CO)(PPh3)2(L2)] (3) and [RuCl(CO)(AsPh3)2(L2)] (4) were synthesized by reactions of [RuHCl(CO)(EPh3)3] (E = P or As) precursors with hydrazone ligands and characterized by analytical and spectroscopic methods. The molecular structure of complex 2 was identified by means of single-crystal X-ray diffraction analysis. The structural analysis revealed that all the complexes possess a distorted octahedral geometry with the ligand coordinating in a uni-negative bidentate NO fashion. Further, the catalytic efficiency of the complexes have been investigated in the case of direct amidation of alcohols with amines. The influence of base, reaction temperature and catalyst loading in the amidation reaction was also evaluated. Notably, complex 3 was found to be very efficient catalyst towards amidation of alcohols with amine. A variety of aromatic (hetero) amines and alcohols with various functional groups have also been successfully used for amidations.
- Selvamurugan, Sellappan,Ramachandran, Rangasamy,Prakash, Govindan,Viswanathamurthi, Periasamy,Malecki, Jan Grzegorz,Endo, Akira
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supporting information
p. 119 - 127
(2015/12/30)
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- Iron-Catalyzed Directed C(sp2)-H and C(sp3)-H Functionalization with Trimethylaluminum
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Conversion of a C(sp2)-H or C(sp3)-H bond to the corresponding C-Me bond can be achieved by using AlMe3 or its air-stable diamine complex in the presence of catalytic amounts of an inorganic iron(III) salt and a diphosphine along with 2,3-dichlorobutane as a stoichiometric oxidant. The reaction is applicable to a variety of amide substrates bearing a picolinoyl or 8-aminoquinolyl directing group, enabling methylation of a variety of (hetero)aryl, alkenyl, and alkyl amides. The use of the mild aluminum reagent prevents undesired reduction of iron and allows the reaction to proceed with catalyst turnover numbers as high as 6500.
- Shang, Rui,Ilies, Laurean,Nakamura, Eiichi
-
supporting information
p. 7660 - 7663
(2015/06/30)
-
- A Heterogeneous Niobium(V) Oxide Catalyst for the Direct Amidation of Esters
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This study reports the first example of a heterogeneous catalytic system for the direct amidation of various esters with amines. Of 25 types of catalyst, Nb2O5 shows the highest activity in the amidation of methyl benzoate with aniline. Nb2O5 gives high yields in the amidation of various esters and amines under solvent-free conditions, is reusable, and shows higher turnover numbers than previously reported homogeneous catalysts such as La(OTf)3. IR spectroscopic studies of ethyl acetate adsorbed on the catalysts show a strong acid-base interaction between the Nb5+ Lewis acid site and carbonyl oxygen, which can result in high reactivity of the ester with a nucleophile (amine) and, thus, high activity of Nb2O5. Kinetic results show that the activity of Nb2O5 does not markedly decrease with increasing aniline concentration, in contrast to reference catalysts TiO2 and La(OTf)3. The relatively low negative impact of basic molecules on the Lewis acid catalysis of Nb2O5 also enables its high activity.
- Ali, Md. Ayub,Siddiki, S. M. A. Hakim,Kon, Kenichi,Shimizu, Ken-Ichi
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p. 2705 - 2710
(2015/09/15)
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- Cu(I)-catalyzed transannulation of N -heteroaryl aldehydes or ketones with alkylamines via C(sp3)-H amination
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A copper(I)-catalyzed direct transannulation of N-heteroaryl aldehydes or ketones with alkylamines via Csp3-H amination has been achieved using molecular oxygen as a sole oxidant. N-Heteroarenes are employed as the amine source. This transformation provides a rapid and concise access to multifunctional imidazo[1,5-a]pyridines.
- Li, Mingyang,Xie, Ying,Ye, Yong,Zou, Yong,Jiang, Huanfeng,Zeng, Wei
-
supporting information
p. 6232 - 6235
(2015/02/19)
-
- B(OCH2CF3)3-mediated direct amidation of pharmaceutically relevant building blocks in cyclopentyl methyl ether
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The use of B(OCH2CF3)3 for mediating direct amidation reactions of a wide range of pharmaceutically relevant carboxylic acids and amines is described, including numerous heterocycle-containing examples. An initial screen of solvents for the direct amidation reaction suggested that cyclopentyl methyl ether, a solvent with a very good safety profile suitable for use over a wide temperature range, was an excellent replacement for the previously used solvent acetonitrile. Under these conditions amides could be prepared from 18 of the 21 carboxylic acids and 18 of the 21 amines examined. Further optimisation of one of the low yielding amidation reactions (36% yield) via a design of experiments approach enabled an 84% yield of the amide to be obtained.
- Karaluka, Valerija,Lanigan, Rachel M.,Murray, Paul M.,Badland, Matthew,Sheppard, Tom D.
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supporting information
p. 10888 - 10894
(2015/11/17)
-
- s-triazene based fluorous coupling reagent for direct amide synthesis
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Abstract A new simple and efficient fluorous coupling reagent TriTFET (2,4,6-tris-(2,2,2-trifluoro-ethoxy)-[1,3,5] triazene) has been designed and synthesized for the direct amidation. The use of 5 mol % of TriTFET is good for the amide synthesis from carboxylic acids with amines in moderate to excellent yields (72-96%).
- Mangawa, Shrawan Kumar,Bagh, Sangram Keshari,Sharma, Kumkum,Awasthi, Satish K.
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supporting information
p. 1960 - 1963
(2015/03/18)
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- Selective Monoesterification of Symmetrical Diols Using Resin-Bound Triphenylphosphine
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Coupling reactions to make esters and amides are among the most widely used organic transformations. We report efficient procedures for amide bond formation and for the monoesterification of symmetrical diols in excellent yields without any requirement for high dilution or slow addition using resin-bound triarylphosphonium iodide. Easy purification, low moisture sensitivity, and good to excellent yields of the products are the major advantages of this protocol.
- Pathak, Gunindra,Rokhum, Lalthazuala
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supporting information
p. 483 - 487
(2015/09/22)
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- Amidation of Carboxylic Acids with Amines by Nb2O5 as a Reusable Lewis Acid Catalyst
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Among 28 types of heterogeneous and homogenous catalysts tested, Nb2O5 shows the highest yield for direct amidation of n-dodecanoic acid with a less reactive amine (aniline). The catalytic amidation by Nb2O5 is applicable to a wide range of carboxylic acids and amines with various functional groups, and the catalyst is reusable. A comparison of the results of the catalytic study and an infrared study of the acetic acid adsorbed on the catalyst suggests that activation of the carbonyl group of the carboxylic acid by Lewis acid sites on Nb2O5 is responsible for the high activity of the Nb2O5 catalyst. Kinetic studies show that Lewis acid sites on Nb2O5 are more water-tolerant than conventional Lewis acidic oxides (Al2O3, TiO2). In comparison with the state-of-the-art homogeneous Lewis acid catalyst for amidation (ZrCl4), Nb2O5 undergoes fewer negative effects from basic additives in the solution, which indicates that Nb2O5 is a more base-tolerant Lewis acid catalyst than the homogeneous Lewis acid catalyst.
- Ali,Siddiki,Onodera, Wataru,Kon, Kenichi,Shimizu, Ken-Ichi
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p. 3555 - 3561
(2015/11/10)
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- Carboxyl activation via silylthioesterification: One-pot, two-step amidation of carboxylic acids catalyzed by non-metal ammonium salts
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The first organo-catalyzed silylthioesterification of a carboxylic acid and a commercially available mercaptoorganosilane results in the in situ production of an O-silylthionoester. Subsequent amine addition forms amides in an operationally simple one-pot procedure without removal of water. The scope and efficiency of these reactions with respect to the catalyst, carboxylic acid, amine, [Si-S] moiety, and solvent are investigated. A number of functionalities are tolerated in the two-step amidation including alkene, alkyne, alkyl and aryl halides, benzylic ethers, and heterocycles with free coordinating sites.
- Lamar, Angus A.,Liebeskind, Lanny S.
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supporting information
p. 6034 - 6037
(2015/10/28)
-
- Designing of thermally stable amide functionalized benzimidazolium perchlorate ionic liquid for transamidation of primary carboxamides
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In the present work, we have designed and synthesized a thermally stable catalyst based on functionalized benzimidazolium perchlorate ionic liquid and tested its efficacy towards metal free and solvent free transamidation of amides and amines. The ionic liquid comprising the perchlorate ion has shown remarkably better activity than those which contain other anions and accordingly a plausible mechanism for the catalytic activity is arrived. The developed catalytic system has shown excellent activity towards the transamidation of alicyclic and aromatic amines with acetamide, benzamide and p-nitrobenzamide under mild conditions. Furthermore, the transamidation of nicotinamide with benzylamine in presence of the ionic liquid catalyst was found to occur with very good yields and thus provides a facile route for the synthesis of pharmaceutically significant compounds. The catalyst has exhibited very good thermal stability upto 203 °C and very good recyclability upto 5 runs without significant loss in its activity.
- Muskawar, Prashant Narayan,Thenmozhi,Bhagat, Pundlik Rambhau
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p. 158 - 167
(2015/09/28)
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- Size of gold nanoparticles driving selective amide synthesis through aerobic condensation of aldehydes and amines
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Metal nanoparticles (NPs) have attracted much attention in many fields due to their intrinsic characteristics. It is generally accepted that smaller NPs (1.5-3 nm) are more active than larger NPs, and reverse cases are very rare. We report here the direct aerobic oxidative amide synthesis from aldehydes and amines catalyzed by polymer-incarcerated gold (Au) NPs. A unique correlation between imine/amide selectivity and size of NPs was discovered; Au-NPs of medium size (4.5-11 nm) were found to be optimal. High yields were obtained with a broad range of substrates, including primary amines. Au-NPs of medium size could be recovered and reused several times without loss of activity, and they showed good activity and selectivity in amide formation from alcohols and amines. Superior activity and selectivity of gold nanoparticles (Au-NPs) of medium size (4.5-11 nm) were found for the direct and selective aerobic oxidative amide synthesis from various combinations of aldehydes and amines. This is an example of an unusual correlation between the size of NPs and their activity/selectivity. These catalysts could be recovered and reused several times without loss of activity.
- Miyamura, Hiroyuki,Min, Hyemin,Soulé, Jean-Fran?ois,Kobayashi, Shu
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supporting information
p. 7564 - 7567
(2015/06/25)
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- Synergistic cascade catalysis by metal nanoparticles and Lewis acids in hydrogen autotransfer
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Of the many types of catalysis involving two or more catalysts, synergistic catalysis is of great interest because novel reactions or reaction pathways may be discovered when there is synergy between the catalysts. Herein, we describe a synergistic cascade catalysis, in which immobilized Au/Pd bimetallic nanoparticles and Lewis acids work in tandem to achieve the N-alkylation of primary amides to secondary amides with alcohols via hydrogen autotransfer. When Au/Pd nanoparticles were used with metal triflates, a significant rate acceleration was observed, and the desired secondary amides were obtained in excellent yields. The metal triflate is thought to not only facilitate the addition of primary amides to aldehydes generated in situ, but also enhance the returning of hydrogen from nanoparticles to hydrogen-accepting intermediates. This resulted in a more rapid turnover of the nanoparticle catalyst, and ultimately translated into an increase in the overall rate of the reaction. The two catalysts in this co-catalytic system work in a synergistic and cascade fashion, resulting in an efficient hydrogen autotransfer process.
- Choo, Gerald C. Y.,Miyamura, Hiroyuki,Kobayashi, Shuˉ
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p. 1719 - 1727
(2015/08/12)
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- Catalyst and method for producing the same
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PROBLEM TO BE SOLVED: To provide a method for producing an amide compound from a primary alcohol and at least one selected from a primary amine, a secondary amine and derivatives of those under relatively mild conditions with high selectivity and a high conversion ratio.SOLUTION: A method for producing an amide compound comprises a step of obtaining the amide compound from a primary alcohol and at least one selected from a primary amine, a secondary amine and derivatives of those, in the presence of a catalyst comprising a carrier formed by crosslinking a crosslinkable functional group of a styrene-based polymer having a side chain containing the crosslinkable functional group, and a nanosize cluster and carbon black supported on the carrier, wherein the nanosize cluster is at least one selected from a nanosize gold cluster and a nanosize cluster of gold and at least one group 8 metal selected from iron, cobalt and nickel.
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Paragraph 0073; 0075; 0079
(2016/11/07)
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- Rh(III)-catalyzed cascade oxidative olefination/cyclization of picolinamides and alkenes via C-H activation
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Rh(III)-catalyzed cascade oxidative alkenylation/cyclization of picolinamides and alkenes to furnish pyrido pyrrolone derivatives is described, in which three C-H bonds and one N-H bond broke, while one C-C bond and one C-N bond formed. The reaction proceeded with high yield and high regioselectivity and stereoselectivity. Moreover, copper acetate can also be used in catalytic amounts with O2 serving as the terminal oxidant.
- Cai, Shangjun,Chen, Chao,Shao, Peng,Xi, Chanjuan
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p. 3142 - 3145
(2014/06/23)
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- Synthesis of alkylidene pyrrolo[3,4-b]pyridin-7-one derivatives via Rh III-catalyzed cascade oxidative alkenylation/annulation of picolinamides
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A practical RhIII-catalyzed cascade olefination/annulation of picolinamides leading to pyrrolo[3,4-b]pyridines has been developed. The reaction shows wide scope, complete regiocontrol and excellent stereoselectivity. This journal is the Partner Organisations 2014.
- Martínez, ángel Manu,Rodríguez, Nuria,Gómez Arrayás, Ramón,Carretero, Juan C.
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supporting information
p. 6105 - 6107
(2014/06/09)
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- Triphenylphosphine-catalysed amide bond formation between carboxylic acids and amines
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Unactivated carboxylic acids and amines undergo organocatalytic Ph 3P/CCl4-mediated amide bond formation by employing in situ reduction of triphenylphosphine oxide to triphenylphosphine in the presence of diethoxymethylsilane and bis(4-nitrophenyl)phosphate. the Partner Organisations 2014.
- Lenstra, Danny C.,Rutjes, Floris P. J. T.,Mecinovi?, Jasmin
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supporting information
p. 5763 - 5766
(2014/05/20)
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- Lanthanum(III) triflate catalyzed direct amidation of esters
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Lanthanum trifluoromethanesulfonate is an effective single-component catalyst for synthesizing a variety of amides directly from esters and amines under mild conditions. Highly selective amidation of esters and amines, as well as catalyst-controlled amidation of esters, demonstrated the effectiveness of the catalyst system.
- Morimoto, Hiroyuki,Fujiwara, Risa,Shimizu, Yuhei,Morisaki, Kazuhiro,Ohshima, Takashi
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supporting information
p. 2018 - 2021
(2014/05/06)
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- Iron pentacarbonyl in alkoxy- and aminocarbonylation of aromatic halides
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We have identified reaction conditions for a Heck-type carbonylation based on [Fe(CO)5]. Preliminary optimization of alkoxycarbonylation on 2-bromonaphthalene defined functioning composition of the reaction mixture which was then applied on a small set of (hetero)aromatic halides. Respective aminocarbonylation of these halides with different amines, including aniline and benzotriazole, was accomplished with reasonable results.
- Babjak, Matej,Caletková, O?ga,?uri?ová, Diana,Gracza, Tibor
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supporting information
p. 2579 - 2584
(2015/01/09)
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- Direct synthesis of amides from coupling of alcohols and amines catalyzed by ruthenium(II) thiocarboxamide complexes under aerobic conditions
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Four octahedral ruthenium(II) thiocarboxamide complexes of the general formula [RuClCO(AsPh3)2(L)] (L = N-substituted pyridine-2-thiocarboxamide) incorporating carbonyl and triphenylarsine have been synthesized from the reaction of 1 equiv of ruthenium precursor [RuHClCO(AsPh3)3] with 1 equiv of thiocarboxamide ligands in refluxing ethanol in the presence of base. All the new complexes have been fully characterized by means of elemental analysis, IR, UV-vis, and NMR spectral methods. Molecular structures of all the complexes were determined by X-ray crystallography, which confirm the coordination mode of thiocarboxamide and reveal the presence of a distorted octahedral geometry around the Ru ion. All the ruthenium(II) thiocarboxamide complexes were generated as highly efficient catalysts for synthesis of secondary or tertiary amides by coupling of amines and alcohols with low catalyst loading, and the maximum yield was obtained up to 97%. The coupling reaction can be readily carried out under mild aerobic conditions, and release of water is the only byproduct. Further, the effect of substituents of the ligand, solvents, reaction temperature, time, and catalyst loading on the catalytic activity of the complexes has been investigated. A plausible mechanism is proposed for the synthesis of amides via hemiaminal as intermediate through an oxidation of an alcohol to aldehyde.
- Sindhuja, Elangovan,Ramesh, Rengan,Balaji, Sundarraman,Liu, Yu
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p. 4269 - 4278
(2014/12/09)
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- Synthesis of imides by palladium-catalyzed C-H functionalization of aldehydes with secondary amides
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An efficient palladium-catalyzed C-H functionalization of aldehydes with various N-substituted N-heteroarene-2-carboxamides has been developed for the synthesis of secondary imides. The reaction tolerates various functionalities, such as methoxy, fluoro, chloro, and bromo groups. A tentative radical mechanism for a PdII/PdIV catalytic cycle is proposed. Copyright
- Bian, Yong-Jun,Chen, Chao-Yue,Huang, Zhi-Zhen
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p. 1129 - 1133
(2013/02/23)
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- Scope and limitations of auxiliary-assisted, palladium-catalyzed arylation and alkylation of sp2 and sp3 C-H bonds
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The scope of palladium-catalyzed, auxiliary-assisted direct arylation and alkylation of sp2 and sp3 C-H bonds of amine and carboxylic acid derivatives has been investigated. The method employs a palladium acetate catalyst, substrate, aryl, alkyl, benzyl, or allyl halide, and inorganic base in tert-amyl alcohol or water solvent at 100-140 C. Aryl and alkyl iodides as well as benzyl and allyl bromides are competent reagents in this transformation. The picolinic acid auxiliary is used for amine γ-functionalization, and the 8-aminoquinoline auxiliary is used for carboxylic acid β-functionalization. Some optimization of base, additives, and solvent is required for achieving best results.
- Nadres, Enrico T.,Santos, Gerson Ivan Franco,Shabashov, Dmitry,Daugulis, Olafs
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p. 9689 - 9714
(2013/10/22)
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- Iodination of remote ortho-C-H bonds of arenes via directed S EAr: A streamlined synthesis of tetrahydroquinolines
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A new strategy for the synthesis of tetrahydroquinolines (THQs) via the sequential functionalizations of remote C-H bonds is reported. This method uses a single picolinamide directing/protecting group to effect Pd-catalyzed γ-C(sp3)-H arylation, metal-free ε-C(sp2)-H iodination, and Cu-catalyzed intramolecular C-N cross-coupling. The overall sequence is efficient and versatile, and offers a streamlined synthesis of THQs with complex substitution patterns from readily available aryl iodide and aliphatic amine precursors.
- Nack, William A.,He, Gang,Zhang, Shu-Yu,Lu, Chengxi,Chen, Gong
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supporting information
p. 3440 - 3443
(2013/07/26)
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- Green and selective synthesis of N-substituted amides using water soluble porphyrazinato copper(II) catalyst
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N,N',N",N"'-Tetramethyl tetra-2,3-pyridinoporphyrazinato copper(II) methyl sulfate ([Cu(2,3-tmtppa)](MeSO4)4) efficiently catalyzed the direct conversion of nitriles to N-substituted amides. The one pot selective synthesis of the N-substituted amides from nitriles and primary amines was performed in refluxing H2O. The catalyst was recovered and reused at least four times,maintaining its efficiency.
- Ghodsinia, Sara S. E.,Akhlaghinia, Batool,Safaei, Elham,Eshghi, Hossein
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p. 895 - 903
(2013/08/23)
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- Direct amidation from alcohols and amines through a tandem oxidation process catalyzed by heterogeneous-polymer-incarcerated gold nanoparticles under aerobic conditions
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We describe herein a highly elegant and suitable synthesis of amide products from alcohols and amines through a tandem oxidation process that uses molecular oxygen as a terminal oxidant. Carbon-black-stabilized polymer-incarcerated gold (PICB-Au) or gold/cobalt (PICB-Au/Co) nanoparticles were employed as an efficient heterogeneous catalyst depending on alcohol reactivity and generated only water as the major co-product of the reaction. A wide scope of substrate applicability was shown with 42 examples. The catalysts could be recovered and reused without loss of activity by using a simple operation. Gold standard: A highly efficient green method for amide synthesis from alcohols and amines catalyzed by gold nanoparticles stabilized by styrene-based copolymers has been developed (see scheme). Two catalysts have been used with high selectivity depending on the combination of substrates. These Au nanoparticle catalysts can be recovered and reused several times by simple operations. Copyright
- Soule, Jean-Francois,Miyamura, Hiroyuki,Kobayashi, Shu
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supporting information
p. 2614 - 2626
(2013/11/19)
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- Aerobic oxidative coupling of alcohols and amines over Au-Pd/resin in water: Au/Pd molar ratios switch the reaction pathways to amides or imines
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A facile switch of the reaction pathways of aerobic oxidative coupling of alcohols and amines from amidation to imination was realized for the first time by tuning the Au/Pd ratios in ion-exchange resin supported Au-Pd alloy catalysts (Au-Pd/resin). Amides were obtained with high yields on Au6Pd/resin while imines were obtained over AuPd4/resin. Various alcohols and amines underwent oxidative coupling smoothly in water to afford the desired products with good to excellent yields. Further investigation on the reaction mechanism suggested the synergistic effect between Au and Pd determined the adsorption strength of the aldehyde intermediate, which in turn dictated the reaction pathways. That is, on Au-rich alloys (e.g., Au6Pd) absorbed aldehyde species was formed, followed by further oxidation to yield amides, while on Pd-rich alloys (e.g., AuPd4), free aldehyde was generated, which then underwent condensation with amines to produce imines. The discovery might provide avenues to develop new efficient catalysts for the green synthesis of special chemicals.
- Zhang, Leilei,Wang, Wentao,Wang, Aiqin,Cui, Yitao,Yang, Xiaofeng,Huang, Yanqiang,Liu, Xiaoyan,Liu, Wengang,Son, Jin-Young,Oji, Hiroshi,Zhang, Tao
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supporting information
p. 2680 - 2684
(2013/10/08)
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- Palladium-catalyzed alkenylation and alkynylation of ortho-C(sp 2)-H bonds of benzylamine picolinamides
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An efficient functionalization of ortho-C(sp2)-H bonds of picolinamide (PA)-protected benzylamine substrates with a range of vinyl iodides as well as acetylenic bromide is reported. ortho-Phenyl benzoic acid (oPBA) acts as an effective promoter in this reaction system. This method provides a practical strategy to access highly functionalized benzylamine compounds for organic synthesis.
- Zhao, Yingsheng,He, Gang,Nack, William A.,Chen, Gong
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supporting information; experimental part
p. 2948 - 2951
(2012/08/07)
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