1122-56-1Relevant academic research and scientific papers
Half-Sandwich Iridium Complexes for the One-Pot Synthesis of Amides: Preparation, Structure, and Diverse Catalytic Activity
Fan, Xiao-Nan,Deng, Wei,Liu, Zhen-Jiang,Yao, Zi-Jian
, p. 16582 - 16590 (2020)
Several types of air-stable N,O-coordinate half-sandwich iridium complexes containing Schiff base ligands with the general formula [Cp*IrClL] were synthesized in good yields. These stable iridium complexes displayed a good catalytic efficiency in amide synthesis. A variety of amides with different substituents were obtained in a one-pot procedure with excellent yields and high selectivities through the amidation of aldehydes with NH2OHHCl and nitrile hydration under the catalysis of complexes 1-4. The excellent and diverse catalytic activity, mild conditions, broad substance scope, and environmentally friendly solvent make this system potentially applicable in industrial production. Half-sandwich iridium complexes 1-4 were characterized by NMR, elemental analysis, and IR techniques. Molecular structures of complexes 2 and 3 were confirmed by single-crystal X-ray analysis.
A general and practical oxidation of alcohols to primary amides under metal-free conditions
Wu, Xiao-Feng,Sharif, Muhammad,Feng, Jian-Bo,Neumann, Helfried,Pews-Davtyan, Anahit,Langer, Peter,Beller, Matthias
, p. 1956 - 1961 (2013)
A general procedure for oxidation of both benzyl alcohols and alkyl alcohols to primary amides under catalyst free conditions has been developed. 34 examples of primary amides were produced from their corresponding alcohols in moderate to excellent yields. This is a practical procedure for primary amides synthesis; water and tert-butanol are the only by-products. A commercial drug, Piracetam, was prepared in one step with 73% yield as well.
Chemoselective hydrogenation of heteroarenes and arenes by Pd-Ru-PVP under mild conditions
Abe, Naoya,Chaudhari, Chandan,Ikeda, Yasuyuki,Kitagawa, Hiroshi,Kusuda, Kohei,Matsumura, Syo,Nagaoka, Katsutoshi,Nishida, Yoshihide,Sato, Katsutoshi,Terada, Kenji,Toriyama, Takaaki,Yamamoto, Tomokazu
, p. 44191 - 44195 (2020)
Monometallic (Pd, Ru or Rh) and bimetallic (Pd0.5-Ru0.5) alloy NPs catalysts were examined for the hydrogenation of quinoline. Pd-Ru alloy catalyst showed superior catalytic activity to the traditional Rh catalyst. The characterization of Pd0.5-Ru0.5 catalysts, HAADF-EDX mapping and XPS analysis suggested that the alloy state of PdRu catalysts remained unchanged in the recovered catalyst. Furthermore, the catalyst was highly selective for the hydrogenation of different arenes. This journal is
RhI-catalyzed hydration of organonitriles under ambient conditions
Goto, Akihiro,Endo, Kohei,Saito, Susumu
, p. 3607 - 3609 (2008)
(Chemical Presented) New scoop on scope and selectivity: The hydration of organonitriles catalyzed by a RhI(OMe) species under nearly pH-neutral and ambient conditions (25°C, 1 atm) is chemoselective and high-yielding (93 to 99%), has a broad substrate scope, and may thus be complementary to enzymatic hydration methods for the introduction of a terminal amido group (CONH2) onto a carbon chain.
Phosphinous Acid-Assisted Hydration of Nitriles: Understanding the Controversial Reactivity of Osmium and Ruthenium Catalysts
González-Fernández, Rebeca,Crochet, Pascale,Cadierno, Victorio,Menéndez, M. Isabel,López, Ramón
, p. 15210 - 15221 (2017)
The synthesis and catalytic behavior of the osmium(II) complexes [OsCl2(η6-p-cymene)(PR2OH)] [R=Me (2 a), Ph (2 b), OMe (2 c), OPh (2 d)] in nitrile hydration reactions is presented. Among them, the best catalytic results were obtained with the phosphinous acid derivative [OsCl2(η6-p-cymene)(PMe2OH)] (2 a), which selectively provided the desired primary amides in excellent yields and short times at 80 °C, employing directly water as solvent, and without the assistance of any basic additive (TOF values up to 200 h?1). The process was successful with aromatic, heteroaromatic, aliphatic, and α,β-unsaturated organonitriles, and showed a high functional group tolerance. Indeed, complex 2 a represents the most active and versatile osmium-based catalyst for the hydration of nitriles reported so far in the literature. In addition, it exhibits a catalytic performance similar to that of its ruthenium analogue [RuCl2(η6-p-cymene)(PMe2OH)] (4). However, when compared to 4, the osmium complex 2 a turned out to be faster in the hydration of less-reactive aliphatic nitriles, whereas the opposite trend was generally observed with aromatic substrates. DFT calculations suggest that these differences in reactivity are mainly related to the ring strain associated with the key intermediate in the catalytic cycle, that is, a five-membered metallacyclic species generated by intramolecular addition of the hydroxyl group of the phosphinous acid ligand to the metal-coordinated nitrile.
An environmentally benign electrochemical process for the reduction of carboxylic acid hydrazides to amides
Mentel, Matthias,Beier, Matthias J.,Breinbauer, Rolf
, p. 1463 - 1468 (2009)
The transformation of acid hydrazides to primary amides is of certain relevance for the organic synthesis of complex molecules. While existing methods require harsh reaction conditions, we present an electrochemical approach in which monoacylhydrazines are reduced to primary amides in 40-90% yield in a divided electrochemical cell with a tin cathode. This method proved superior to reduction by sodium/mercury or lithium/biphenyl in terms of yield and practicability. Most importantly, the new method is distinguished by its tolerance of aryl halogen and olefinic groups. Georg Thieme Verlag Stuttgart.
Activation of nitriles by silver(I) N-heterocyclic carbenes: An efficient on-water synthesis of primary amides
Thirukovela, Narasimha Swamy,Balaboina, Ramesh,Kankala, Shravankumar,Vadde, Ravindhar,Vasam, Chandra Sekhar
, p. 2637 - 2641 (2019)
A first example of silver(I) N-heterocyclic carbene (Ag(I)-NHC) catalyzed on-water synthesis of primary amides by hydration of nitriles under mild reaction conditions is described. This organometallic catalytic system has excellent tolerance for various homo-aromatic, hetero-aromatic and aliphatic nitriles to afford primary amides in good yields in neat water.
Investigation of binap-based hydroxyphosphine arene-ruthenium(II) complexes as catalysts for nitrile hydration
Toms-Mendivil, Eder,Menndez-Rodrguez, Luca,Francos, Javier,Crochet, Pascale,Cadierno, Victorio
, p. 63466 - 63474 (2014)
The binap-based hydroxyphosphine-(η6-arene)-ruthenium(ii) complexes [RuX{η6:κ1(P)-PPh2-binaphthyl}{PPh2(OH)}][OTf] (X = OTf (4), Cl (5)) have been evaluated as potential catalysts for the selective hydration of nitriles to primary amides. The triflate derivative 4 proved to be the most active, being able to hydrate a large variety of aromatic, heteroaromatic, α,β-unsaturated and aliphatic nitriles in pure water at 100°C. The utility of complex 4 to promote the catalytic rearrangement of aldoximes has also been demonstrated. In addition, insights about the role played by the hydroxyphosphine ligand PPh2(OH) during the catalytic reactions are given.
Half-Sandwich Iridium Complexes Based on β-Ketoamino Ligands: Preparation, Structure, and Catalytic Activity in Amide Synthesis
Wang, Yang,Guo, Wen,Guan, Ai-Lin,Liu, Shuang,Yao, Zi-Jian
, p. 11514 - 11520 (2021/07/31)
A series of β-ketoamino-based N,O-chelate half-sandwich iridium complexes with the general formula [Cp*IrClL] have been prepared in good yields. These air-insensitive iridium complexes showed desirable catalytic activity in an amide preparation under mild conditions. A number of amides with diverse substituted groups were furnished in a one-pot reaction with good-to-excellent yields through an amidation reaction of NH2OH·HCl with aldehydes in the presence of these iridium(III) precursors. The excellent catalytic activity, mild reaction conditions, and broad substrate scope gave this type of iridium catalyst potential for use in industry. All of the obtained iridium complexes were well characterized by different spectroscopy techniques. The exact molecular structure of complex 3 has been confirmed by single-crystal X-ray analysis.
A Molecular Iron-Based System for Divergent Bond Activation: Controlling the Reactivity of Aldehydes
Chatterjee, Basujit,Jena, Soumyashree,Chugh, Vishal,Weyhermüller, Thomas,Werlé, Christophe
, p. 7176 - 7185 (2021/06/30)
The direct synthesis of amides and nitriles from readily available aldehyde precursors provides access to functional groups of major synthetic utility. To date, most reliable catalytic methods have typically been optimized to supply one product exclusively. Herein, we describe an approach centered on an operationally simple iron-based system that, depending on the reaction conditions, selectively addresses either the C=O or C-H bond of aldehydes. This way, two divergent reaction pathways can be opened to furnish both products in high yields and selectivities under mild reaction conditions. The catalyst system takes advantage of iron's dual reactivity capable of acting as (1) a Lewis acid and (2) a nitrene transfer platform to govern the aldehyde building block. The present transformation offers a rare control over the selectivity on the basis of the iron system's ionic nature. This approach expands the repertoire of protocols for amide and nitrile synthesis and shows that fine adjustments of the catalyst system's molecular environment can supply control over bond activation processes, thus providing easy access to various products from primary building blocks.
