587-51-9Relevant academic research and scientific papers
Visible-Light- And PPh3-Mediated Direct C-N Coupling of Nitroarenes and Boronic Acids at Ambient Temperature
Manna, Kartic,Ganguly, Tanusree,Baitalik, Sujoy,Jana, Ranjan
supporting information, p. 8634 - 8639 (2021/11/01)
We present here a metal-free, visible-light- and triphenylphosphine-mediated intermolecular, reductive amination between nitroarenes and boronic acids at ambient temperature without any photocatalyst. Mechanistically, a slow reduction of nitroarenes to a nitroso and, finally, a nitrene intermediate occurs that leads to the amination product with concomitant 1,2-aryl/-alkyl migration from a boronate complex. A wide range of nitroarenes underwent C-N coupling with aryl-/alkylboronic acids providing high yields.
A terphenyl phosphine as a highly efficient ligand for palladium-catalysed amination of aryl halides with 1° anilines
Shi, Ji-cheng,Zhang, Lixue,Zhou, Fabin
, p. 238 - 243 (2021/09/07)
A terphenyl phosphine ligand (2,6-bis(2,4,6-triisopropylphenyl)phenyl-dicyclohexylphosphine, TXPhos) and its supported palladium complex [(TXPhos)(allyl)PdCl] have been developed and the catalyst system is highly efficient in amination of aryl halides with 1° anilines, especially effective for densely functionalized substrates including both partners possessing ortho-ester, acetyl, nitrile and nitro groups. With the TXPhos-supported catalyst system, many partner combinations have been unprecedentedly realized and the base scope has been even extended to KOAc, which is even the best choice in the amination of 2-nitrochlorobenzene.
Palladium-catalyzed amination of aryl sulfoxides
Yoshida, Yuto,Otsuka, Shinya,Nogi, Keisuke,Yorimitsu, Hideki
supporting information, p. 1134 - 1137 (2018/02/23)
Amination of diaryl sulfoxides with anilines and alkylamines has been accomplished under palladium/N-heterocyclic carbene (NHC) catalysis. Owing to its electron deficiency, the leaving arenesulfenate anion would be smoothly released from the palladium center to result in uneventful catalyst turnover under milder reaction conditions in comparison with previous C-S bond amination reactions. This amination accommodated a wider range of functional groups such as silyl, boryl, methylsulfanyl, and halogen moieties. Regioselective amination of unsymmetrical diaryl sulfoxides was also executed by means of steric bias.
Buchwald-Hartwig Amination of (Hetero)Aryl Tosylates Using a Well-Defined N-Heterocyclic Carbene/Palladium(II) Precatalyst
Zhang, Yin,Lavigne, Guy,César, Vincent
, p. 7666 - 7673 (2015/08/18)
The cross-coupling of aryl tosylates with amines and anilines was achieved by using for the first time a Pd-NHC system based on the popular Pd-PEPPSI precatalyst platform in which the anchoring imidazol-2-ylidene ligand IPr (NMe2)2 incorporates two dimethylamino groups as backbone substituents enhancing both the electronic and steric properties of the carbene. The system optimization and its application scope are disclosed.
Palladium-catalyzed amination of aryl sulfides with anilines
Sugahara, Tomohiro,Murakami, Kei,Yorimitsu, Hideki,Osuka, Atsuhiro
supporting information, p. 9329 - 9333,5 (2014/11/07)
A combination of a palladium-NHC catalyst and potassium hexamethyldisilazide enables the amination of aryl sulfides with anilines to afford a wide variety of diarylamines. The reaction conditions are versatile enough for the reaction of even bulky ortho-substituted aryl sulfides. This amination can be applied to the modular synthesis of N-aryl carbazoles from the corresponding ortho-bromothioanisoles. As aryl sulfoxides undergo extended Pummerer reactions to afford ortho-substituted aryl sulfides, the Pummerer products are thus useful substrates for the amination to culminate in efficient syntheses of a 2-anilinobenzothiophene and an indole as proof-of-principle of the utility of the extended Pummerer reaction/amination cascade. Switching S to N: Transformation of inert C-S bonds of aryl sulfides into C-N bonds is achieved using a palladium complex with an N-heterocyclic carbene ligand. Thanks to the efficient conditions for amination of bulky sulfides, the synthesis of carbazole products from 2-biphenylylamine is achieved through oxidative C-N bond formation. When combined with extended Pummerer reactions, intriguing nitrogen-containing molecules are prepared.
Large yet flexible N-heterocyclic carbene ligands for palladium catalysis
Meiries, Sebastien,Le Duc, Gaetan,Chartoire, Anthony,Collado, Alba,Speck, Klaus,Arachchige, Kasun S. Athukorala,Slawin, Alexandra M. Z.,Nolan, Steven P.
supporting information, p. 17358 - 17368 (2014/01/06)
A straightforward and scalable eight-step synthesis of new N-heterocyclic carbenes (NHCs) has been developed from inexpensive and readily available 2-nitro-m-xylene. This process allows for the preparation of a novel class of NHCs coined ITent ("Tent" for "tentacular") of which the well-known IMes (N,N′-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene), IPr (N,N′-bis(2,6-di(2-propyl)phenyl)imidazol-2-ylidene) and IPent (N,N′-bis(2,6-di(3-pentyl)phenyl)imidazol-2-ylidene) NHCs are the simplest and already known congeners. The synthetic route was successfully used for the preparation of three members of the ITent family: IPent (N,N′-bis(2,6- di(3-pentyl)phenyl)imidazol-2-ylidene), IHept (N,N′-bis(2,6-di(4-heptyl) phenyl)imidazol-2-ylidene) and INon (N,N′-bis(2,6-di(5-nonyl)phenyl) imidazol-2-ylidene). The electronic and steric properties of each NHC were studied through the preparation of both nickel and palladium complexes. Finally the effect of these new ITent ligands in Pd-catalyzed Suzuki-Miyaura and Buchwald-Hartwig cross-couplings was investigated. Tentacular NHCs: A straightforward, scalable eight-step synthesis of N-heterocyclic carbenes (NHCs) has been developed using inexpensive and readily available 2-nitro-m-xylene, allowing the preparation of a class of NHCs designated ITent ("Tent" for "tentacular"). The electronic and steric properties of each NHC were studied through the preparation of both nickel and palladium complexes, and the effect of these new ITent ligands in Pd-catalyzed Suzuki-Miyaura and Buchwald-Hartwig cross-couplings was investigated.
Buchwald-Hartwig amination of (hetero)aryl chlorides by employing Mor-DalPhos under aqueous and solvent-free conditions
Tardiff, Bennett J.,Stradiotto, Mark
experimental part, p. 3972 - 3977 (2012/08/27)
We report on the application of the [Pd(cinnamyl)Cl]2/Mor- DalPhos catalyst system in the Buchwald-Hartwig amination of (hetero)aryl chlorides with primary or secondary amines conducted either under aqueous conditions without the use of co-solvents and/or surfactants or under solvent-free conditions (52 examples). We have established that reactions of this type can be conducted without the rigorous exclusion of air, and in the case of the solvent-free reactions, we have demonstrated that appropriately selected liquid and solid reagents can be employed successfully.
Rational and predictable chemoselective synthesis of oligoamines via Buchwald-Hartwig amination of (hetero)aryl chlorides employing Mor-Dalphos
Tardiff, Bennett J.,McDonald, Robert,Ferguson, Michael J.,Stradiotto, Mark
experimental part, p. 1056 - 1071 (2012/02/15)
We report a diverse demonstration of synthetically useful chemoselectivity in the synthesis of di-, tri-, and tetraamines (62 examples) by use of Buchwald-Hartwig amination employing a single catalyst system ([Pd(cinnamyl)Cl]2/L1; L1 = N-(2-(di(1-adamantyl)phosphino)phenyl) morpholine, Mor-DalPhos). Competition reactions established the following relative preference of this catalyst system for amine coupling partners: linear primary alkylamines and imines > unhindered electron-rich primary anilines, primary hydrazones, N,N-dialkylhydrazines, and cyclic primary alkylamines > unhindered electron-deficient primary anilines, α-branched acyclic primary alkylamines, hindered electron-rich primary anilines ? cyclic and acyclic secondary dialkylamines, secondary alkyl/aryl and diarylamines, α,α-branched primary alkylamines, and primary amides. The new isomeric ligand N-(4-(di(1-adamantyl)phosphino)phenyl)morpholine (p-Mor-DalPhos, L2) was prepared in 63% yield and was crystallographically characterized; the [Pd(cinnamyl)Cl]2/L2 catalyst system exhibited divergent reactivity. Application of the reactivity trends established for [Pd(cinnamyl)Cl] 2/L1 toward the chemoselective synthesis of di-, tri-, and tetraamines was achieved. Preferential arylation was observed at the primary alkylamine position within 2-(4-aminophenyl)ethylamine with [Pd(cinnamyl)Cl] 2/L1 and 4-chlorotoluene (affording 5a); the alternative regioisomer (5a′) was obtained when using [Pd(cinnamyl)Cl]2/L2. These observations are in keeping with coordination chemistry studies, whereby binding of 2-(4-aminophenyl)ethylamine to the in situ generated [(L1)Pd(p-tolyl)] + fragment occurred via the primary amine moiety, affording the crystallographically characterized adduct [(L1)Pd(p-tolyl)(NH2CH 2CH2(4-C6H4NH2)] +OTf- (7) in 72% yield.
