619-76-1Relevant academic research and scientific papers
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.
Method for preparing derivatives of benzamide under microwave condition in aqueous phase
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Paragraph 0018; 0095, (2019/03/28)
The invention discloses a method for preparing derivatives of benzamide under a microwave condition in an aqueous phase. A coupling reaction is carried out between substituted benzoic acid and amine under the microwave condition in the aqueous phase. The method for preparing the derivatives of benzamide is environmentally friendly, easy and convenient to operate, safe, low in cost and efficient. Compared with the prior art, the method can be applicable to a large number of functional groups, is high in yield, produces fewer by-products, and further is easy to operate, safe, low in cost and environmentally friendly. A formula is shown in the description.
Novel design of recyclable copper(II) complex supported on magnetic nanoparticles as active catalyst for Beckmann rearrangement in poly(ethylene glycol)
Keyhaniyan, Mahdi,Shiri, Ali,Eshghi, Hossein,Khojastehnezhad, Amir
, (2018/05/23)
Copper complex-functionalized magnetic core–shell nanoparticles (Fe3O4@SiO2-Lig-Cu) were prepared and characterized using various techniques. The activity of the new catalyst was tested for the Beckmann rearrangement. The reaction conditions allow for the conversion of a wide variety of aldoximes, including aromatic and heterocyclic ones, to amides in good to excellent yields. High efficiency, mild reaction conditions, easy work-up, use of poly(ethylene glycol) as a green medium and simple purification of products are important advantages of this system. Moreover, the eco-friendly heterogeneous nanocatalyst could be easily recovered from the reaction mixture using an external magnet and reused several times.
One-Pot Preparation of Aromatic Amides, 4-Arylthiazoles, and 4-Arylimidazoles from Arenes
Yamamoto, Takahiro,Togo, Hideo
, p. 4187 - 4196 (2018/08/21)
Simple treatment of arenes with α-bromoacetyl chloride and AlCl3, followed by the reaction with molecular iodine and aq. NH3, thioamides, or amidines gave the corresponding primary aromatic amides, 4-arylthiazoles, or 4-arylimidazoles in good yields, respectively. Aryl α-bromomethyl ketones are the key intermediates in those reactions. Primary aromatic amides were formed from arenes through the reaction of aryl α-bromomethyl ketones with molecular iodine and aq. NH3, and 4-arylthiazoles and 4-arylimidazoles were formed from arenes through the reactions of aryl α-bromomethyl ketones with thioamides and amidines, respectively, in one pot under transition-metal-free conditions.
A method of from [...] amide
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Paragraph 0029-0032, (2017/01/31)
The invention discloses a method for synthesizing amides from oxime. The method is characterized by adding oxime, water and a water-soluble iridium complex catalyst to a reaction vessel, cooling a reactant to the room temperature after the reaction mixture reacts at 80-120 DEG C for several hours, removing water through selective evaporation, and obtaining a target product through column separation. Compared with existing methods for synthesizing amides through oxime rearrangement in water through transition metal catalysis, the method has the advantages that the used catalyst is low in load and does not contain phosphine ligands severely polluting the environment, so that the reaction can be carried out in the air, without nitrogen protection; therefore the reaction meets the green chemical requirements and has an extensive development prospect.
Rearrangement of aldoximes to amides in water under air atmosphere catalyzed by water-soluble iridium complex [Cp*Ir(H2O) 3][OTf]2
Sun, Chunlou,Qu, Panpan,Li, Feng
, p. 988 - 996 (2014/04/03)
In the presence of the water-soluble iridium complex [Cp*Ir(H 2O)3][OTf]2, a variety of aldoximes, including aromatic, aliphatic, conjugated unsaturated and non-conjugated unsaturated, were converted into their corresponding amides in water with good to excellent yields. Further, the one-pot synthesis of amides from aldehydes, hydroxylamine hydrochloride and sodium carbonate via a tandem condensation-rearrangement reaction in water was also accomplished. Compared with the reported organometallic catalysts for the rearrangement of aldoximes to amides in water, the present catalyst exhibited some advantages such as being phosphorus ligand-free, having low catalyst loading, and operational convenience under air atmosphere. This journal is the Partner Organisations 2014.
High-temperature synthesis of amides from alcohols or aldehydes by using flow chemistry
Ambreen, Nida,Wirth, Thomas
, p. 7590 - 7593 (2015/04/22)
An efficient conversion of aliphatic and aromatic alcohols or aldehydes into the corresponding primary amides was successfully achieved by using flow chemistry. Excellent yields were obtained in very short reaction times, and thus this method offers an efficient alternative to traditional methods for amide formation.
Copper-catalyzed aerobic oxidative C-C bond cleavage for C-N bond formation: From ketones to amides
Tang, Conghui,Jiao, Ning
supporting information, p. 6528 - 6532 (2014/06/24)
A novel copper-catalyzed aerobic oxidative C(CO)-C(alkyl) bond cleavage reaction of aryl alkyl ketones for C-N bond formation is described. A series of acetophenone derivatives as well as more challenging aryl ketones with long-chain alkyl substituents could be selectively cleaved and converted into the corresponding amides, which are frequently found in biologically active compounds and pharmaceuticals.
One-pot oximation-Beckmann rearrangement of ketones and aldehydes to amides of industrial interest: Acetanilide, caprolactam and acetaminophen
Aricò, Fabio,Quartarone, Giuseppe,Rancan, Elia,Ronchin, Lucio,Tundo, Pietro,Vavasori, Andrea
, p. 47 - 51 (2014/03/21)
High yielding one-pot oximation-Beckmann rearrangement of ketones to amides in ktrifluoroacetic acid has been conducted on several ketones and aldehydes. The substrate reactivity showed to depend on both oximation and Beckmann rearrangement reaction rate. In this synthetic procedure, trifluoroacetic acid acts as solvent, acid catalyst and organocatalyst and can be easily recycled.
Benzamide synthesis by direct electrophilic aromatic substitution with cyanoguanidine
Naredla, Rajasekhar Reddy,Klumpp, Douglas A.
experimental part, p. 4779 - 4781 (2012/09/07)
Cyanoguanidine is an inexpensive commodity chemical and it is found to be a useful reagent for the direct Friedel-Crafts carboxamidation of arenes. The reaction works best in an excess of Bronsted superacid, an observation suggesting the involvement of a superelectrophilic intermediate. Theoretical calculations indicate that the most stable diprotonated species involves protonation at the guanidine and cyano nitrogen atoms.
