10278-46-3Relevant articles and documents
Amide Synthesis from Thiocarboxylic Acids and Amines by Spontaneous Reaction and Electrosynthesis
Tang, Li,Matuska, Jack H.,Huang, Yu-Han,He, Yan-Hong,Guan, Zhi
, p. 2570 - 2575 (2019)
Amide bond formation is one of the most important basic reactions in chemistry. A catalyst-free approach for constructing amide bonds from thiocarboxylic acids and amines was developed. The mechanistic studies showed that the disulfide was the key intermediate for this amide synthesis. Thiobenzoic acids could be automatically oxidized to disulfides in air, thioaliphatic acids could be electro-oxidized to disulfides, and the resulting disulfides reacted with amines to give the corresponding amides. By this method, various amides could be easily synthesized in excellent yields without using any catalyst or activator. The successful synthesis of bioactive compounds also highlights the synthetic utility of this strategy in medicinal chemistry.
Facile conversion of thioamides into the corresponding amides in the presence of tetrabutylammonium bromide
Inamoto, Kiyofumi,Shiraishi, Mitsugu,Hiroya, Kou,Doi, Takayuki
, p. 3087 - 3090 (2010)
Desulfurization of thioamides was accomplished using a semicatalytic amount of Bu4NBr. The corresponding amides were obtained in high yields, with good functional group compatibility. Georg Thieme Verlag Stuttgart - New York.
Examining the Impact of Heteroaryl Variants of PAd-DalPhos on Nickel-Catalyzed C(sp2)-N Cross-Couplings
Clark, Jillian S. K.,McGuire, Ryan T.,Lavoie, Christopher M.,Ferguson, Michael J.,Stradiotto, Mark
, p. 167 - 175 (2019)
We report herein on the synthesis of new heteroaryl analogues of PAd-DalPhos and related bis(di(o-tolyl)phosphino) ancillary ligand variants based on pyridine or thiophene backbone structures, and their application in nickel-catalyzed C(sp2)-N cross-couplings under challenging reaction conditions. The 3,4-disubstituted thiophene-based ancillary ligand ThioPAd-DalPhos (L8) was observed to be particularly effective in the nickel-catalyzed C(sp2)-N cross-coupling of primary alkylamines, and the derived precatalyst (L8)NiCl(o-tolyl) (C2) was found to offer improved performance versus the related PAd-DalPhos-derived precatalyst C1 in such transformations. In using C2, cross-couplings of various primary alkylamines and (hetero)aryl-X electrophiles (X = Cl, Br, OTs) proceeded under unprecedentedly mild reaction conditions (0.25-0.50 mol % Ni), including examples conducted at room temperature. Also reported herein are the results of our combined experimental/DFT computational study directed toward gaining insight regarding the improved catalytic performance of C2 versus C1.
Nickel-Catalyzed N-Arylation of Primary Amides and Lactams with Activated (Hetero)aryl Electrophiles
Lavoie, Christopher M.,MacQueen, Preston M.,Stradiotto, Mark
, p. 18752 - 18755 (2016)
The first nickel-catalyzed N-arylation of amides with (hetero)aryl (pseudo)halides is reported, enabled by use of the air-stable pre-catalyst (PAd-DalPhos)Ni(o-tolyl)Cl (C1). A range of structurally diverse primary amides and lactams were cross-coupled successfully with activated (hetero)aryl chloride, bromide, triflate, tosylate, mesylate, and sulfamate electrophiles.
Bisphosphine-Ligated Nickel Pre-catalysts in C(sp2)–N Cross-Couplings of Aryl Chlorides: A Comparison of Nickel(I) and Nickel(II)
Lavoie, Christopher M.,McDonald, Robert,Johnson, Erin R.,Stradiotto, Mark
, p. 2972 - 2980 (2017)
The influence of ancillary ligand and nickel oxidation state in the nickel-catalyzed C(sp2)–N cross-coupling of aryl chlorides is examined by use of experimental and DFT methods for the first time, focusing on (L)NiCl and (L)Ni(o-tolyl)Cl pre-catalysts (PAd-DalPhos, L1; dppf, L2). Whereas Ni(II) pre-catalysts generally out-performed Ni(I) species in our study, the viability and in some cases superiority of Ni(I) pre-catalysts in challenging aminations is established. Computational analyses support the viability of Ni(0)/Ni(II) cycles featuring rate-limiting C–N reductive elimination, as well as parallel Ni(I)/Ni(III) mechanisms involving rate-limiting C–Cl oxidative addition. (Figure presented.).
Potassium tert-Butoxide Prompted Highly Efficient Transamidation and Its Coordination Radical Mechanism
Tan, Zhiyong,Li, Zhenhua,Ma, Yao,Qin, Jinjing,Yu, Chuanming
, p. 4538 - 4545 (2019)
A simple and highly efficient protocol was developed for the transamidation of N,N-disubstituted amides with primary amines in the presence of tBuOK, affording desired products in good to excellent yields. This reaction proceeded under nitrogen atmosphere and featured extensive substrate tolerance. Experimental investigation suggested that a coordination radical process enhanced this transformation.
N,N-carbonyldiimidazole-mediated amide coupling: Significant rate enhancement achieved by acid catalysis with imidazole - HCI
Woodman, Emily K.,Chaffey, Julian G. K.,Hopes, Philip A.,Hose, David R. J.,Gilday, John P.
, p. 106 - 113 (2009)
Over a series of 10 aromatic amines we show the rate of CDI mediated amidation to be significantly enhanced upon introduction of imidazole·HCI as a proton source for acid catalysis. Our work supports and provides an application for previous investigations into the imidazolium effect, thus increasing the scope of CDI as an amide-coupling reagent with aromatic amines. The influence of the relative pKa of the amines studied on the rate of reaction was also investigated.
Supported-Pd catalyzed tandem approach for N-arylbenzamides synthesis
Bhattacherjee, Dhananjay,Das, Pralay,Giri, Kousik,Shaifali,Sharma, Ajay Kumar,Sharma, Navneet,Sheetal
, (2021/11/24)
Aryl iodides as dual arylating agent for C-terminal from oxalic acid [(CO2H)2] and N-terminal from sodium azide (NaN3) for N-aryl benzamides (Ar-CO-NH-Ar) synthesis is a rare invention which has been attempted successfully under this study. A single step tandem approach for the synthesis of N-aryl benzamides has been developed through bifunctional transformation of aryl iodides with in-situ CO from (CO2H)2 and NaN3 following two different pathways of carbonylation and azidation. The polystyrene supported palladium (Pd@PS) catalyst was found to be well compatible to perform the domino-reaction in a double layer vial (DLV) system under base, ligand and additive-free conditions. Moreover, the same approach was further extended with aryl azides for unsymmetric N-aryl benzamides (Ar-CO-NH-Ar') synthesis. Furthermore, the DFT studies were also performed to support the proposed mechanism.
A practical and sustainable protocol for direct amidation of unactivated esters under transition-metal-free and solvent-free conditions
Chen, Cheng,Cheng, Hua,Du, Min-Chen,Qian, Liang,Qin, Xin,Sang, Wei,Yao, Wei-Zhong,Yuan, Ye,Zhang, Rui
supporting information, p. 3972 - 3982 (2021/06/17)
In this paper, a NaOtBu-mediated synthesis approach was developed for direct amidation of unactivated esters with amines under transition-metal-free and solvent-free conditions, affording a series of amides in good to excellent yields at room temperature. In particular, an environmentally friendly and practical workup procedure, which circumvents the use of organic solvents and chromatography in most cases, was disclosed. Moreover, the gram-scale production of representative products3a,3wand3auwas efficiently realized by applying operationally simple, sustainable and practical procedures. Furthermore, this approach was also applicable to the synthesis of valuable molecules such as moclobemide (a powerful antidepressant), benodanil and fenfuram (two commercial agricultural fungicides). These results demonstrate that this protocol has the potential to streamline amide synthesis in industry. Meanwhile, quantitative green metrics of all the target products were evaluated, implying that the present protocol is advantageous over the reported ones in terms of environmental friendliness and sustainability. Finally, additional experiments and computational calculations were carried out to elucidate the mechanistic insight of this transformation, and one plausible mechanism was provided on the basis of these results and the related literature reports.
