5827-78-1Relevant academic research and scientific papers
Carboxylic Acid Deoxyfluorination and One-Pot Amide Bond Formation Using Pentafluoropyridine (PFP)
Brittain, William D. G.,Cobb, Steven L.
supporting information, p. 5793 - 5798 (2021/08/01)
This work describes the application of pentafluoropyridine (PFP), a cheap commercially available reagent, in the deoxyfluorination of carboxylic acids to acyl fluorides. The acyl fluorides can be formed from a range of acids under mild conditions. We also demonstrate that PFP can be utilized in a one-pot amide bond formation via in situ generation of acyl fluorides. This one-pot deoxyfluorination amide bond-forming reaction gives ready access to amides in yields of ≤94%.
Cross-Dehydrogenative Cyclization-Dimerization Cascade Sequence for the Synthesis of Symmetrical 3,3′-Bisoxindoles
Dobah, Farhaan,Mazodze, C. Munashe,Petersen, Wade F.
supporting information, p. 5466 - 5470 (2021/07/31)
The synthesis of symmetrical 3,3′-bisoxindoles from simple acyclic β-oxoanilides is reported. The described method forges three new C-C bonds in a single step via a sequential Mn(OAc)3·2H2O mediated oxidative radical cyclization-fragmentation-dimerization process. The scope of this reaction is demonstrated in the preparation of a variety of 3,3′-bisoxindoles, as well as its application toward the formal synthesis of the Calycanthaceae alkaloid, (±)-folicanthine.
N-Heterocyclic Carbene/Cobalt Cooperative Catalysis for the Chemo- and Regioselective C?N Bond Formation between Aldehyde and Amines/Amides
Siddiqui, Asher M.,Khalid, Anam,Khan, Arif,Azad, Chandra S.,Samim, Mohd.,Khan, Imran A.
, p. 4281 - 4287 (2020/07/24)
A novel methodology for the construction of various secondary (4 examples), tertiary amides (31 examples), and imides (16 examples) by a Cobalt(II) catalyzed oxidative amide coupling in aqueous media. The Co(III)-TMC was reacted with N-Heteroatom Carbene to form active catalyst Co(II)NHC-TMC in situ which involves in the coordination with Breslow's intermediate and SET for the activation of aldehyde and amides. The mechanism for activation of amide and amine differs on the basis of SET based nucleophilic addition and ligand exchange respectively. The regeneration of the catalyst was achieved using Fe(III)(EDTA)-H2O2 as oxidant. The use of Co(II)TMC-O2 was also found equally efficient in the process. The method is found regioselective for N?H activation in the presence of equally susceptible ortho-C?H bond activation. And amines were found more susceptible then the corresponding amide for the reaction.
An efficient synthesis of benzothiazole using tetrabromomethane as a halogen bond donor catalyst
Kazi, Imran,Sekar, Govindasamy
, p. 9743 - 9756 (2019/12/02)
An efficient and mild protocol has been developed for the synthesis of 2-substituted benzothiazole under solvent- and metal-free conditions using CBr4 as the catalyst. This process involves the activation of a thioamide through halogen bond formation between the sulphur atom of the thioamide and bromine atom of the CBr4 molecule. The presence of halogen-bonding interaction between N-methylthioamides and tetrabromomethane has been demonstrated with several control experiments, spectroscopic analysis and density functional theory (DFT). This methodology has a wide substrate scope for the synthesis of both 2-alkyl and 2-aryl substituted benzothiazoles.
Clickable coupling of carboxylic acids and amines at room temperature mediated by SO2F2: A significant breakthrough for the construction of amides and peptide linkages
Wang, Shi-Meng,Zhao, Chuang,Zhang, Xu,Qin, Hua-Li
, p. 4087 - 4101 (2019/04/30)
The construction of amide bonds and peptide linkages is one of the most fundamental transformations in all life processes and organic synthesis. The synthesis of structurally ubiquitous amide motifs is essential in the assembly of numerous important molecules such as peptides, proteins, alkaloids, pharmaceutical agents, polymers, ligands and agrochemicals. A method of SO2F2-mediated direct clickable coupling of carboxylic acids with amines was developed for the synthesis of a broad scope of amides in a simple, mild, highly efficient, robust and practical manner (>110 examples, >90% yields in most cases). The direct click reactions of acids and amines on a gram scale are also demonstrated using an extremely easy work-up and purification process of washing with 1 M aqueous HCl to provide the desired amides in greater than 99% purity and excellent yields.
Amide Bond Formation Catalyzed by Recyclable Copper Nanoparticles Supported on Zeolite Y under Mild Conditions
Moglie, Yanina,Buxaderas, Eduardo,Mancini, Agustina,Alonso, Francisco,Radivoy, Gabriel
, p. 1487 - 1494 (2019/02/16)
A series of catalysts based on supported copper nanoparticles have been prepared and tested in the amide bond formation from tertiary amines and acid anhydrides, in the presence of tert-butyl hydroperoxide as an oxidant. Copper nanoparticles on zeolite Y (CuNPs/ZY) was found to be the most efficient catalyst for the synthesis of amides, working in acetonitrile as solvent, under ligand- and base-free conditions in air. The products were obtained in good to excellent yields and in short reaction times. The CuNPs/ZY system also exhibited higher catalytic activity than some commercially available copper and iron sources and it was reused in ten reaction cycles without any further pre-treatment. This methodology has been successfully scaled-up to a gram scale with no detriment to the yield.
Transfer Hydro-dehalogenation of Organic Halides Catalyzed by Ruthenium(II) Complex
You, Tingjie,Wang, Zhenrong,Chen, Jiajia,Xia, Yuanzhi
, p. 1340 - 1346 (2017/02/10)
A simple and efficient Ru(II)-catalyzed transfer hydro-dehalogenation of organic halides using 2-propanol solvent as the hydride source was reported. This methodology is applicable for hydro-dehalogenation of a variety of aromatic halides and α-haloesters and amides without additional ligand, and quantitative yields were achieved in many cases. The potential synthetic application of this method was demonstrated by efficient gram-scale transformation with catalyst loading as low as 0.5 mol %.
Substrate scope in the copper-mediated construction of bis-oxindoles via a double C-H/Ar-H coupling process
Drouhin, Pauline,Hurst, Timothy E.,Whitwood, Adrian C.,Taylor, Richard J.K.
supporting information, p. 7124 - 7136 (2015/03/30)
Abstract The synthesis of bis-oxindoles via the copper(II)-mediated double cyclisation of linear bis-anilides is described. Cu(OAc)2·H2O was identified as an efficient and inexpensive catalyst for this process. In contrast to previous methods, which rely on the synthesis of the central core from existing oxindole building blocks, this new approach focusses on concurrent formation of both oxindole rings from a simple linear precursor, allowing the formation of bis-oxindoles containing a diverse range of cyclic and acyclic linkers using a single synthetic method.
A Baker-Venkataraman retro-Claisen cascade delivers a novel alkyl migration process for the synthesis of amides
Ameen, Dana,Snape, Timothy J.
supporting information, p. 1816 - 1819 (2015/03/30)
A simple extension of the carbamoyl Baker-Venkataraman rearrangement has been developed. If residual water in the reaction is not strictly excluded a Baker-Venkataraman retro-Claisen cascade takes place, giving amide products, in which an alkyl group apparently migrates between two functionalities of the substrate.
Copper-mediated construction of spirocyclic bis-oxindoles via a double C-H, Ar-H coupling process
Drouhin, Pauline,Hurst, Timothy E.,Whitwood, Adrian C.,Taylor, Richard J.K.
supporting information, p. 4900 - 4903 (2015/04/27)
A double C-H, Ar-H coupling process for the conversion of bis-anilides into spirocyclic bis-oxindoles, enabling the concomitant formation of two all-carbon quaternary centers at oxindole 3-positions in a diastereoselective manner, is described. The optimum cyclization conditions utilize stoichiometric Cu(OAc)2·H2O/KOtBu in DMF at 110 °C and have been applied to prepare a range of structurally diverse bis-spirooxindoles in fair to good yields (28-77%); the method has also been extended to prepare bis-oxindoles linked by a functionalized acyclic carbon chain.
