411209-38-6Relevant academic research and scientific papers
Photocatalytic aldehydes/alcohols/toluenes oxidative amidation over bifunctional Pd/MOFs: Effect of Fe-O clusters and Lewis acid sites
Bian, Fengxia,Cheng, Hongmei,Jiang, Heyan,Sun, Bin,Tan, Jiangwei,Zang, Cuicui
, p. 279 - 287 (2021/08/21)
Heterogeneous photocatalytic organic synthesis is fascinating because of the utilization of ubiquitous solar light for chemical transformations. Here, three Fe-MOFs with different Fe-O clusters, Lewis acid sites and morphologies were synthesized through coordination structure engineering. Pd/Fe-MOFs nanocomposites were used to challenge the amide bond green synthesis with visible light. Pd/MIL-101(Fe) exhibited the best photocatalytic performance due to the easily excited Fe3-μ3-oxo clusters for light absorption, the efficient photogenerated carriers separation and migration, the large amount of Lewis acid sites based aldehydes and amines condensation promotion and the efficient O2 reduction to superoxide radicals over photogenerated electron-rich Pd NPs. Various aldehydes, alcohols and toluenes could be transformed to amide compounds with amines over Pd/MIL-101(Fe) with just oxygen or air as the green oxidant and water as the by-product. One-pot C–C cross-coupling and photo-redox C–N coupling cascade reactions could also be achieved over Pd/MIL-101(Fe). This work shed light on the efficient and sustainable amide bonds synthesis.
Palladium-Catalyzed Aminocarbonylation of Aryl Halides with N,N-Dialkylformamide Acetals
Hirata, Shuichi,Osako, Takao,Uozumi, Yasuhiro
, (2021/10/05)
We developed a protocol for the palladium-catalyzed aminocarbonylation of aryl halides using less-toxic formamide acetals as bench-stable aminocarbonyl sources under neutral conditions. Various aryl (including heteroaryl) halides reacted with N,N-dialkylformamide acetals in the presence of a catalytic amount of tris(dibenzylideneacetone)dipalladium(0)-chloroform adduct and xantphos to give the corresponding aromatic carboxamides at 90–140 °C without any activating agents or bases in up to quantitative chemical yield. This protocol was applied to aryl bromides, aryl iodides, and trifluoromethanesulfonic acid, as well as to relatively less-reactive aryl chlorides. A wide range of functionalities on the aromatic ring of the substrates were tolerated under the aminocarbonylation conditions. The catalytic aminocarbonylation was used to prepare the insect repellent N,N-diethyl-3-methylbenzamide as well as a synthetic intermediate of the dihydrofolate reductase inhibitor triazinate.
Hydrosilylative reduction of primary amides to primary amines catalyzed by a terminal [Ni-OH] complex
Pandey, Pragati,Bera, Jitendra K.
supporting information, p. 9204 - 9207 (2021/09/20)
A terminal [Ni-OH] complex1, supported by triflamide-functionalized NHC ligands, catalyzes the hydrosilylative reduction of a range of primary amides into primary amines in good to excellent yields under base-free conditions with key functional group tolerance. Catalyst1is also effective for the reduction of a variety of tertiary and secondary amides. In contrast to literature reports, the reactivity of1towards amide reduction follows an inverse trend,i.e., 1° amide > 3° amide > 2° amide. The reaction does not follow a usual dehydration pathway.
Palladium-Catalyzed Desulfurative Amide Formation from Thioureas and Arylboronic Acids
Su, Jianke,Li, Wendong,Li, Xin,Xu, Jian,Song, Qiuling
, p. 5664 - 5668 (2020/10/02)
The development of the reactivity on carbene complexes would lead to the creation of novel synthetic strategies. We discovered herein the Pd-catalyzed desulfurative amide formation involved Suzuki-Miyaura coupling reaction, notably the Pd complex was generated in situ from thioureas, Ag salt and Pd catalyst. Silver salt was essential for the construction of this type of carbenes from available and stable thioureas and well participated in the catalytic cycle. We report a method for the synthesis of arylamides from arylboronic acids, which greatly enriched the application of thiourea chemistry and expanded the application of the Suzuki-Miyaura coupling.
Oxidative Amidation of Amines in Tandem with Transamidation: A Route to Amides Using Visible-Light Energy
Nandi, Jyoti,Vaughan, Matthew Z.,Sandoval, Arturo León,Paolillo, Joshua M.,Leadbeater, Nicholas E.
, p. 9219 - 9229 (2020/08/14)
A methodology is reported for preparing amides using amines as an acyl source. The protocol involves the visible-light-promoted oxidative amidation of amines with pyrazole to synthesize N-acyl pyrazoles followed by transamidation. By combining photoredox catalysis with oxoammonium cations in the presence of sodium persulfate as a terminal oxidant, the N-acyl pyrazoles could be prepared efficiently and effectively using blue LEDs. The transamidation step was performed without the need to purify the N-acyl pyrazole intermediate, and a range of amides were generated in good to excellent yields.
Cobalt-catalyzed aminocarbonylation of (hetero)aryl halides promoted by visible light
Alexanian, Erik J.,Veatch, Alexander M.
, p. 7210 - 7213 (2020/07/23)
The catalytic aminocarbonylation of (hetero)aryl halides is widely applied in the synthesis of amides but relies heavily on the use of precious metal catalysis. Herein, we report an aminocarbonylation of (hetero)aryl halides using a simple cobalt catalyst under visible light irradiation. The reaction extends to the use of (hetero)aryl chlorides and is successful with a broad range of amine nucleophiles. Mechanistic investigations are consistent with a reaction proceeding via intermolecular charge transfer involving a donor-acceptor complex of the substrate and cobaltate catalyst.
Amide Synthesis by Nickel/Photoredox-Catalyzed Direct Carbamoylation of (Hetero)Aryl Bromides
Alandini, Nurtalya,Buzzetti, Luca,Candish, Lisa,Collins, Karl D.,Favi, Gianfranco,Melchiorre, Paolo,Schulte, Tim
supporting information, p. 5248 - 5253 (2020/03/03)
Herein, we report a one-electron strategy for catalytic amide synthesis that enables the direct carbamoylation of (hetero)aryl bromides. This radical cross-coupling approach, which is based on the combination of nickel and photoredox catalysis, proceeds at ambient temperature and uses readily available dihydropyridines as precursors of carbamoyl radicals. The method's mild reaction conditions make it tolerant of sensitive-functional-group-containing substrates and allow the installation of an amide scaffold within biologically relevant heterocycles. In addition, we installed amide functionalities bearing electron-poor and sterically hindered amine moieties, which would be difficult to prepare with classical dehydrative condensation methods.
Catalyst-Free, Metal-Free, and Chemoselective Transamidation of Activated Secondary Amides
Ramkumar, Rajagopal,Chandrasekaran, Srinivasan
, p. 921 - 932 (2019/02/10)
A simple protocol, which is catalyst-free, metal-free, and chemoselective, for transamidation of activated secondary amides in ethanol as solvent under mild conditions is reported. A wide range of amines, amino acids, amino alcohols, and the substituents, which are problematic in catalyzed transamidation, are tolerated in this methodology. The transamidation reaction was successfully extended to water as the medium as well. The present methodology appears to be better than the other catalyzed transamidations reported recently.
Visible-Light-Mediated Efficient Metal-Free Catalyst for α-Oxygenation of Tertiary Amines to Amides
Zhang, Yu,Riemer, Daniel,Schilling, Waldemar,Kollmann, Jiri,Das, Shoubhik
, p. 6659 - 6664 (2018/06/25)
A metal-free system has been discovered for the efficient α-oxygenation of tertiary amines to the corresponding amides using oxygen as an oxidant. This visible-light-mediated oxygenation reaction exhibited excellent substrates scope under mild reaction conditions and generated water as the only byproduct. The synthetic utility of this approach has been demonstrated by applying onto drug molecules. At the end, detailed mechanistic reactions clearly showed the role of oxygen and the photocatalyst.
Straightforward α-Amino Nitrile Synthesis Through Mo(CO)6-Catalyzed Reductive Functionalization of Carboxamides
Trillo, Paz,Slagbrand, Tove,Adolfsson, Hans
supporting information, p. 12347 - 12351 (2018/09/10)
The selective reduction of amides into an intermediate hemiaminal catalyzed by Mo(CO)6 together with the inexpensive and easy to handle TMDS (1,1,3,3-tetramethyldisiloxane) as reducing agent, followed by subsequent trapping of the hemiaminal with a cyanide source, allows for the straightforward synthesis of α-amino nitriles. The methodology presented here, displays high levels of chemoselectivity allowing for the reduction of amides in the presence of functional groups such as ketones, imines, aldehydes, and acids, which affords a simple route for the synthesis of α-amino nitriles with a broad scope of functionalities in high yields. Furthermore, the applicability of this methodology is demonstrated by scale up experiments and by derivatization of the target compounds into synthetically interesting products. The selective cyanation is successfully applied in late stage functionalizations of amide containing drugs and prolinol derivatives.
