cas 27347-14-4, 4-(4-METHOXY-PHENYL)-MORPHOLINE

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A novel, safe, and robust nitration process for the synthesis of 4-(4-methoxy-3-nitrophenyl)morpholine
A novel nitration process was developed for the production of 4-(4-methoxy-3-nitrophenyl)morpholine. Crude 4-(4-methoxyphenyl-)morpholine produced in step 1 was converted to its nitric acid salt. The nitration reaction was carried out by adding a dichloro
Pingsheng, Zhang,Shankar, Ashish,Cleary, Thomas P.,Cedilote, Miall,Locklear, Dobbert,Pierce, Michael E.
p. 861 - 864
(2007)
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Pd(η3-1-PhC3H4)(η5- C5H5) as a catalyst precursor for Buchwald-Hartwig amination reactions
The compound Pd(η3-1-Ph-C3H4) (η5-C5H5) (I) reacts cleanly with many tertiary phosphines L to undergo reductive elimination of PhC3H 4-C5H5 and form palladium(0) species of the types PdLn (n = 2, 3), long believed to be exemplary catalysts for Suzuki-Miyaura, Heck-Mizoroki, and Sonogashira cross-coupling reactions. I has accordingly been shown to be generally much more effective for these catalytic processes than are conventional catalyst precursors such as Pd(PPh 3)4, Pd2(dba)3, PdCl2, and Pd(OAc)2, in large part because I stands alone in this series for its ability to generate specifically and efficiently the desired species PdL2 in many cases. We have now investigated I as a precursor for prototypical Buchwald-Hartwig amination reactions of 4-bromo- and 4-chloroanisole with morpholine, making comparisons with Pd2(dba) 3, Pd(OAc)2, and [Pd(η3-1-Ph-C 3H4)Cl]2 (IV). In this work we have utilized PBut3 because of its general effectiveness, and we have also assessed XPhos and Mor-Dalphos, representatives of important classes of phosphines utilized elsewhere for amination reactions.
Borjian, Sogol,Tom, David M. E.,Baird, Michael C.
p. 3928 - 3935
(2014)
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SnCl4 and SbCl5 promoted aromatization of enamines
Aromatic amines have been synthesized efficiently from enamines using SnCl4 and SbCl5 in CH2Cl2 at room temperature.
Bigdeli, Mohammad Ali,Rahmati, Abbas,Abbasi-Ghadim, Hossein,Mahdavinia, Gholam Hossein
p. 4575 - 4578
(2007)
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Experimental and theoretical investigations of new dinuclear palladium complexes as precatalysts for the amination of aryl chlorides
A series of new palladium dinuclear species with general formula [Pd 2X(μ-X){μ- PtBu2(Bph-R)}] (X = Cl, Br; Bph = biphenyl; R = H, Me, NMe2) have been prepared. The two palladium centers in these species are bridged by one of the aromatic rings of the biphenyl group present in the corresponding phosphine. The X-ray crystal structure of one of these complexes has been obtained, providing a clear picture of the bonding pattern. The stability of these dimers in solution is shown to be highly dependent on the nature of the phosphine R group and also on the bridging halide. When R = NMe2, the dimers dissociate, yielding the palladium(II) compounds PdX2{PtBu2(BPh-NMe 2)} (X = Cl, Br), and the X-ray crystal structure of one of them (X = Br) has shown that the biphenyl group from the phosphine interacts directly with the metal center. This interaction seems to play an important role in stabilizing the otherwise coordinatively unsaturated palladium(II) complex. In contrast, when R = H or Me, the analogous monomeric palladium(II) complexes are unstable and undergo cyclometalation to generate a palladium(II) dinuclear species in which each of the two phosphines cyclometalates with the palladium centers forming a strained four-membered ring. In addition to their unusual structures, these aryl-bridged dimers have also proven to be excellent precatalysts for the amination of aryl chlorides. To rationalize some of the experimental results, a detailed DFT computational study has been carried out and is presented herein.
Christmann, Ute,Pantazis, Dimitrios A.,Benet-Buchholz, Jordi,McGrady, John E.,Maseras, Feliu,Vilar, Ramon
p. 6376 - 6390
(2006)
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A stable (amino)(phosphino)carbene as bidentate ligand for palladium and nickel complexes: Synthesis, structure, and catalytic activity
Two original complexes featuring an (amino)(phosphino)carbene η2-bonded to the metal have been obtained in 60% and 80% yields, by addition of the corresponding stable carbene to PdCl2(cod) and NiCl2(PPh3)2
Teuma, Emmanuelle,Lyon-Saunier, Céline,Gornitzka, Heinz,Mignani, Gérard,Baceiredo, Antoine,Bertrand, Guy
p. 5541 - 5545
(2005)
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A Simple Synthetic Route to Well-Defined [Pd(NHC)Cl(1-tBu-indenyl)] Pre-catalysts for Cross-Coupling Reactions
The development of robust, more efficient, general, easily accessible Pd(II)–NHC pre-catalysts remains a key issue in cross-coupling applications. A selection of well-defined, air and moisture stable [Pd(NHC)Cl(1-tBu-indenyl)] (NHC=IPr, IPrCl, IMes, SIMes, IPr*) pre-catalysts have been synthesized in good to excellent yields by reacting [Pd(1-tBu-indenyl)(μ-Cl)]2 and various NHC?HCl precursors in the presence of the weak base K2CO3 in green acetone. The synthesized Pd(II)-NHC derivatives displayed excellent catalytic activity in classical Suzuki-Miyaura and Buchwald–Hartwig reactions, especially when IPrCl is employed as ancillary ligand. Additionally, in the challenging Suzuki-Miyaura reaction between esters and arylboronic acids, the [Pd(IPr*)Cl(1-tBu-indenyl)] complex exhibited the optimum catalytic activity under very mild reaction conditions.
Liu, Yaxu,Scattolin, Thomas,Gobbo, Alberto,Beli?, Marek,Van Hecke, Kristof,Nolan, Steven P.,Cazin, Catherine S. J.
(2021/12/22)

Electrochemical Cross-Dehydrogenative Aromatization Protocol for the Synthesis of Aromatic Amines
The introduction of amines onto aromatics without metal catalysts and chemical oxidants is synthetically challenging. Herein, we report the first example of an electrochemical cross-dehydrogenative aromatization (ECDA) reaction of saturated cyclohexanones and amines to construct anilines without additional metal catalysts and chemical oxidants. This reaction exhibits a broad scope of cyclohexanones including heterocyclic ketones, affording a variety of aromatic amines with various functionalities, and shows great potential in the synthesis of biologically active compounds.
Tao, Shao-Kun,Chen, Shan-Yong,Feng, Mei-Lin,Xu, Jia-Qi,Yuan, Mao-Lin,Fu, Hai-Yan,Li, Rui-Xiang,Chen, Hua,Zheng, Xue-Li,Yu, Xiao-Qi
supporting information
p. 1011 - 1016
(2022/02/05)

Product selective reaction controlled by the combination of palladium nanoparticles, continuous microwave irradiation, and a co-existing solid; ligand-free Buchwald-Hartwig aminationvs.aryne amination
We have developed a continuous microwave irradiation-assisted Buchwald-Hartwig amination using our original Pd nanoparticle catalyst with a copper plate as a co-existing metal solid. In this methodology, a microwave-controlled product selectivity was achieved between Buchwald-Hartwig amination and aryne amination performed under strongly basic conditions and at a high reaction temperature, because a polar chemical species such as Ar-Pd-halogen might be activated selectively by microwave radiation. Moreover, our catalyst could be used repeatedly over 10 times, and the amount of Pd leaching could be suppressed to a low level.
Akiyama, Toshiki,Arai, Masayoshi,Arisawa, Mitsuhiro,Haneoka, Hitoshi,Harada, Kazuo,Murai, Kenichi,Murakami, Yosuke,Ohki, Yuuta,Ohta, Ryousuke,Sako, Makoto,Sirimangkalakitti, Natchanun,Suzuki, Takeyuki,Takahashi, Naoyuki,Takehara, Tsunayoshi,Yamada, Makito
supporting information
p. 8131 - 8137
(2021/10/29)

COMPLEXES OF N-HETEROCYCLIC CARBENES FOR TRANSITION METAL CATALYSIS
Described herein is a new class of highly active Pd(II)-NHC complexes bearing anilines as throw-away ligands. These catalysts are well-defined, air- and moisture-stable and can be easily purified by chromatographic techniques. High activity and generality has been exemplified in the Suzuki-Miyaura cross-coupling by C-N, C-O and C-Cl cleavage. Facile syntheses of these catalysts is also described.
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Paragraph 32; 35

(2021/07/17)

IPr# - highly hindered, broadly applicable N-heterocyclic carbenes
IPr (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) represents the most important NHC (NHC = N-heterocyclic carbene) ligand throughout the field of homogeneous catalysis. Herein, we report the synthesis, catalytic activity, and full structural and electronic characterization of novel, sterically-bulky, easily-accessible NHC ligands based on the hash peralkylation concept, including IPr#, Np# and BIAN-IPr#. The new ligands have been commercialized in collaboration with Millipore Sigma: IPr#HCl, 915653; Np#HCl; 915912; BIAN-IPr#HCl, 916420, enabling broad access of the academic and industrial researchers to new ligands for reaction optimization and screening. In particular, the synthesis of IPr# hinges upon cost-effective, modular alkylation of aniline, an industrial chemical that is available in bulk. The generality of this approach in ligand design is demonstrated through facile synthesis of BIAN-IPr# and Np#, two ligands that differ in steric properties and N-wingtip arrangement. The broad activity in various cross-coupling reactions in an array of N-C, O-C, C-Cl, C-Br, C-S and C-H bond cross-couplings is demonstrated. The evaluation of steric, electron-donating and π-accepting properties as well as coordination chemistry to Au(i), Rh(i) and Pd(ii) is presented. Given the tremendous importance of NHC ligands in homogenous catalysis, we expect that this new class of NHCs will find rapid and widespread application.
Flach, Carol,Lalancette, Roger,Li, Guangchen,Mendelsohn, Richard,Meng, Guangrong,Szostak, Michal,Szostak, Roman,Zhao, Qun
p. 10583 - 10589
(2021/08/20)

LIGANDS FOR TRANSITION METAL CATALYSTS
Provided herein are a new class of extremely sterically-bulky, easily prepared N-heterocyclic carbene (NHC) ligands of Formula I, or a salt, solvate, geometric isomer, or stereoisomer thereof. The ligands are readily synthetically accessible exploiting the cost-effective, modular alkylation of anilines, an industrial chemical that is available in bulk. The NHC ligands form effective catalysts with transition metals such as Pd.
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(2021/07/17)

Complexes: Easily Synthesized, Highly Active Pd(II)-NHC Precatalysts for Cross-Coupling Reactions
We report the synthesis, characterization, and reactivity of [(NHC)PdCl2(aniline)] complexes. These well-defined, air- and moisture-stable catalysts are highly active in the Suzuki-Miyaura cross-coupling of amides by N-C(O) activation as well as in the Suzuki-Miyaura cross-coupling of esters, aryl chlorides, and Buchwald-Hartwig amination. Most crucially, this study introduces broadly available anilines as stabilizing ligands for well-defined Pd(II)-NHC catalysts. The availability of various aniline scaffolds, including structural and electronic diversity, has a significant potential in fine-tuning of challenging cross-couplings by Pd-NHCs. The parent catalyst in this class, [Pd(IPr)(AN)Cl2], has been commercialized in collaboration with Millipore Sigma, offering broad access for reaction screening and optimization.
Xia, Qinqin,Shi, Shicheng,Gao, Pengcheng,Lalancette, Roger,Szostak, Roman,Szostak, Michal
p. 15648 - 15657
(2021/10/25)

TRIARYL PHOSPHINE LIGANDS, PREPARATION METHOD THEREFOR, AND USE IN CATALYSING COUPLING REACTIONS
Provided are triaryl phosphine ligands, as shown in general formulae Ia and Ib, or a mixture thereof, and a preparation method therefor. The invention addresses the deficiencies of biaryl phosphine ligands invented by Buchwald et al. Also provided are a triaryl phosphine coordinated palladium complex, a system composed of triaryl phosphine ligand and a palladium salt or complex, and a use of the triaryl phosphine coordinated palladium complex in catalysing organic reactions, in particular a use in catalysis of coupling reactions involving (pseudo)halogenated aromatic hydrocarbon as substrate.
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(2021/05/21)

Synthesis and catalytic activity of palladium complexes bearingN-heterocyclic carbenes (NHCs) and 1,4,7-triaza-9-phosphatricyclo[5.3.2.1]tridecane (CAP) ligands
The synthesis and characterization of novel palladium complexes bearingN-heterocyclic carbenes (NHCs) and 1,4,7-triaza-9-phosphatricyclo[5.3.2.1]tridecane (CAP) are reported. These organometallic complexes can be easily obtained using two different synthetic strategies that involve either the substitution of the pyridine ligand fromtrans-[Pd(NHC)(Py)Cl2] or by simple addition of the CAP ligand to dimeric species [Pd(NHC)Cl2]2. The mixed NHC/CAP complexes were tested as pre-catalysts in the Buchwald-Hartwig aryl amination coupling, showing good catalytic activity, especially in the case ofcis-[Pd(IPr)(CAP)Cl2].
Beli?, Marek,Cazin, Catherine S. J.,Martynova, Ekaterina,Nolan, Steven P.,Scattolin, Thomas,Vanden Broeck, Sofie M. P.,Voloshkin, Vladislav A.
p. 9491 - 9499
(2021/07/17)

N-substituted aminobiphenyl palladacycles stabilized by dialkylterphenyl phosphanes: Preparation and applications in C[sbnd]N cross-coupling reactions
Neutral and cationic N-methyl- and N-phenyl-2-aminobiphenyl methanesulfonate palladacycles stabilized with dialkylterphenyl phosphanes have been prepared and characterized. Neutral structures are favored with the less bulky phosphane PMe2ArXyl2, L1, while more sterically demanding ligands PiPr2ArXyl2, L3, and PCyp2ArXyl2 (Cyp = cyclopentyl), L4, lead to cationic complexes in which the phosphane exhibits a bidentate κ1-P, η1-Carene coordination mode involving one of the ipso carbon atoms of a flanking terphenyl aryl ring. The complexes were evaluated for activity in C[sbnd]N cross-coupling reactions and [Pd(N-methyl-2-aminobiphenyl)L4](OMs) (OMs = mesylate) was identified as the most efficient precatalyst, facilitating the coupling of aryl chlorides with secondary and primary amines and indoles.
Monti, Andrea,Rama, Raquel J.,Gómez, Beatriz,Maya, Celia,álvarez, Eleuterio,Carmona, Ernesto,Nicasio, M. Carmen
supporting information

(2021/01/19)

Selective C-O Bond Reduction and Borylation of Aryl Ethers Catalyzed by a Rhodium-Aluminum Heterobimetallic Complex
We report the catalytic reduction of a C-O bond and the borylation by a rhodium complex bearing an X-Type PAlP pincer ligand. We have revealed the reaction mechanism based on the characterization of the reaction intermediate and deuterium-labeling experiments. Notably, this novel catalytic system shows steric-hindrance-dependent chemoselectivity that is distinct from conventional Ni-based catalysts and suggests a new strategy for selective C-O bond activation by heterobimetallic catalysis.
Hara, Naofumi,Nakao, Yoshiaki,Saito, Teruhiko,Seki, Rin
supporting information
p. 6388 - 6394
(2021/05/31)

Aerobic iron-catalyzed site-selective C(sp3)–C(sp3) bond cleavage in N-heterocycles
The kinetic and thermodynamic stability of C(sp3)–C(sp3) bonds makes the site-selective activation of these motifs a real synthetic challenge. In view of this, herein a site-selective method of C(sp3)–C(sp3) bon
Beller, Matthias,Junge, Kathrin,Leonard, David K.,Li, Wu,Rockstroh, Nils
(2021/06/26)

Effect of Precatalyst Oxidation State in C-N Cross-Couplings with 2-Phosphinoimidazole-Derived Bimetallic Pd(I) and Pd(II) Complexes
We report the catalytic activity of two phosphinoimidazole-derived bimetallic palladium complexes in Pd-catalyzed amination reactions. Our studies demonstrate that the starting oxidation state (Pd(I) or Pd(II)) of the dimeric complex has a significant effect on the efficiency of the catalytic reaction. The corresponding Pd(I) complex shows higher reactivity in Buchwald-Hartwig aminations, while the Pd(II) complex is much more reactive in carbonylative amination reactions. These new dimeric palladium complexes provide good to excellent reactivity and yields in the amination reactions tested.
Martinez, Erin E.,Moreno, Mariur Rodriguez,Barksdale, Caleb A.,Michaelis, David J.
supporting information
p. 2763 - 2767
(2021/08/27)

Amination of Aryl Halides Mediated by Electrogenerated Nickel from Sacrificial Anode
Electrochemical C(sp2)?N couplings mediated by nickel salts generated from the sacrificial anode has been described for the first time. In this approach, the sacrificial nickel anode is employed as the sole source of nickel and the process, operationally simple to set up, enables the preparation of functionalized arylamine derivatives with moderate to good yields, under mild reaction conditions and without additional ligand. A cooperative process between the two electrodes is involved in the proposed mechanism.
Daili, Farah,Sengmany, Stéphane,Léonel, Eric
p. 2462 - 2469
(2021/06/28)

Evidence for "cocktail"-type catalysis in Buchwald-Hartwig reaction. A mechanistic study
The mechanism of the C-N cross-coupling reaction, catalyzed by palladium complexes with N-heterocyclic carbene ligands (Pd/NHC), was evaluated in detail at the molecular and nanoscale levels. For the first time, the formation of a "cocktail"-type catalytic system was proven for the Buchwald-Hartwig reaction. The unique ability of the Pd/NHC system to generate several types of catalytic centers (Pd complexes, clusters and nanoparticles) and the involvement of complementary pathways (homogeneous and heterogeneous) were discovered to take place in a "one pot"manner directly in the reaction vessel. Access to various catalytic centers from a single and readily available Pd/NHC complex is the key to designing a universal catalytic system with adaptive tuning capability. This journal is
Ananikov, Valentine P.,Boiko, Daniil A.,Burykina, Julia V.,Madiyeva, Malena,Minyaev, Mikhail E.,Prima, Darya O.
p. 7171 - 7188
(2021/11/17)

Palladium Complexes Based on Ylide-Functionalized Phosphines (YPhos): Broadly Applicable High-Performance Precatalysts for the Amination of Aryl Halides at Room Temperature
Palladium allyl, cinnamyl, and indenyl complexes with the ylide-substituted phosphines Cy3P+?C?(R)PCy2 (with R=Me (L1) or Ph (L2)) and Cy3P+?C?(Me)PtBu2 (L3) were prepared and applied as defined precatalysts in C?N coupling reactions. The complexes are highly active in the amination of 4-chlorotoluene with a series of different amines. Higher yields were observed with the precatalysts in comparison to the in situ generated catalysts. Changes in the ligand structures allowed for improved selectivities by shutting down β-hydride elimination or diarylation reactions. Particularly, the complexes based on L2 (joYPhos) revealed to be universal precatalysts for various amines and aryl halides. Full conversions to the desired products are reached mostly within 1 h reaction time at room temperature, thus making L2 to one of the most efficient ligands in C?N coupling reactions. The applicability of the catalysts was demonstrated for aryl chlorides, bromides and iodides together with primary and secondary aryl and alkyl amines, including gram-scale applications also with low catalyst loadings of down to 0.05 mol %. Kinetic studies further demonstrated the outstanding activity of the precatalysts with TOF over 10.000 h?1.
Tappen, Jens,Rodstein, Ilja,McGuire, Katie,Gro?johann, Angela,L?ffler, Julian,Scherpf, Thorsten,Gessner, Viktoria H.
supporting information
p. 4281 - 4288
(2020/03/13)

Dialkylterphenyl Phosphine-Based Palladium Precatalysts for Efficient Aryl Amination of N-Nucleophiles
A series of 2-aminobiphenyl palladacycles supported by dialkylterphenyl phosphines, PR2Ar′ (R=Me, Et, iPr, Cyp (cyclopentyl), Ar′=ArDipp2, ArXyl2f, Dipp (2,6-C6H3-(2,6-C6H3-(CHMe2)2)2), Xyl=xylyl) have been prepared and structurally characterized. Neutral palladacycles were obtained with less bulky terphenyl phosphines (i.e., Me and Et substituents) whereas the largest phosphines provided cationic palladacycles in which the phosphines adopted a bidentate hemilabile k1-P,η1-Carene coordination mode. The influence of the ligand structure on the catalytic performance of these Pd precatalysts was evaluated in aryl amination reactions. Cationic complexes bearing the phosphines PiPr2ArXyl2 and PCyp2ArXyl2 were the most active of the series. These precatalysts have demonstrated a high versatility and efficiency in the coupling of a variety of nitrogen nucleophiles, including secondary amines, alkyl amines, anilines, and indoles, with electronically deactivated and ortho-substituted aryl chlorides at low catalyst loadings (0.25–0.75 mol % Pd) and without excess ligand.
Rama, Raquel J.,Maya, Celia,Nicasio, M. Carmen
supporting information
p. 1064 - 1073
(2020/01/25)

Cu(I)-anchored polyvinyl alcohol coated-magnetic nanoparticles as heterogeneous nanocatalyst in Ullmann-type C–N coupling reactions
In this paper, the preparation of a novel magnetic nanocatalyst (Fe3O4?PVA/CuCl) is described, which involves coating of polyvinyl alcohol (PVA) onto the surface of Fe3O4 nanoparticles and its subsequent coordination with CuCl catalyst. The nanocatalyst was characterized by various analytical methods, including Fourier-transform infrared, X-ray diffraction, inductively coupled plasma spectroscopy, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy, vibrating-sample magnetometry, and EDX elemental mapping. Moreover, the nanocatalyst was efficiently used in the N-arylation of amines via the formation of a carbon–nitrogen bond between the aryl halides and amines by Ullmann-type coupling reactions. The catalyst was sufficiently stable and can be reused for at least seven times in a model Ullmann reaction without remarkable alteration in its catalytic behavior. Heterogeneity of the catalyst was investigated by a hot filtration test.
Ahany Kamangar, Sheida,Hashemi Salehi, Mirmehdi,Hekmati, Malak,Hemmati, Saba,Yousefi, Mohammad
(2020/03/13)

Green tea extract–modified silica gel decorated with palladium nanoparticles as a heterogeneous and recyclable nanocatalyst for Buchwald-Hartwig C–N cross-coupling reactions
A novel green tea extract–encapsulated silica gel decorated with in situ–generated Pd nanoparticles is reported as an efficient, green heterogeneous catalyst in the Buchwald-Hartwig C–N cross-coupling reaction. It was characterized by several analytical techniques. Thereafter, a wide range of aryl amines were synthesized in good to excellent yields by reaction of different substituted aryl halides and secondary amines over the catalyst. The material is sufficiently stable and could be used at least six times in a model Buchwald-Hartwig reaction without noticeable change in its catalytic activity. Heterogeneity of the catalyst was examined by a hot filtration test.
Veisi, Hojat,Tamoradi, Taiebeh,Karmakar, Bikash,Hemmati, Saba
(2019/11/28)

Metal-free late-stage C(sp2)-H functionalization of: N -aryl amines with various sodium salts
Metal-free consecutive C(sp2)-X (X = Cl, Br, S, N) bond formations of N-aryl amines (cyclic, fused, carbamate, and aminium radicals) were achieved under mild conditions using [bis(trifluoroacetoxy)iodo]benzene (PIFA) and simple nonharmful sodium salts. This direct and selective C(sp2)-H functionalization showed excellent functional group compatibility, cost effectiveness, and late-stage applicability for the synthesis of biologically active natural products. Two mechanisms were proposed to explain the ortho- or para-preference, as well as the accelerating effect of CH3NO2
Mudithanapelli, Chandrashekar,Kim, Mi-Hyun
p. 450 - 464
(2020/02/03)

Copper-Catalyzed Electrophilic Amination of Alkoxyarylsilanes
We report a copper-catalyzed amination reaction between simple alkoxyarylsilanes and N-benzoyloxyamines. Silver fluoride serves as a stoichiometric base as well as an indispensable activator that allows the catalytic process to proceed. Multiply alkoxylated arylsilanes, such as trialkoxyarylsilanes and dialkoxyarylsilanes were transformed into the corresponding tertiary anilines under mild reaction conditions.
Hitoshio, Kenshiro,Saito, Hayate,Shimokawa, Jun,Yorimitsu, Hideki,Zhang, Qian
supporting information

(2020/07/04)

Nickel-Catalyzed Amination of Aryl Thioethers: A Combined Synthetic and Mechanistic Study
Herein, we report a nickel-1,2-bis(dicyclohexylphosphino)ethane (dcype) complex for the catalytic Buchwald-Hartwig amination of aryl thioethers. The protocol shows broad applicability with a variety of different functional groups tolerated under the catalytic conditions. Extensive organometallic and kinetic studies support a nickel(0)-nickel(II) pathway for this transformation and revealed the oxidative addition complex as the resting state of the catalytic cycle. All the isolated intermediates have proven to be catalytically and kinetically competent catalysts for this transformation. The fleeting transmetalation intermediate has been successfully synthesized through an alternative synthetic organometallic pathway at lower temperature, allowing for in situ NMR study of the C-N bond reductive elimination step. This study addresses key factors governing the mechanism of the nickel-catalyzed Buchwald-Hartwig amination process, thus improving the understanding of this important class of reactions.
Bismuto, Alessandro,Delcaillau, Tristan,Müller, Patrick,Morandi, Bill
p. 4630 - 4639
(2020/05/19)

Ru(II)-Catalyzed Amination of Aryl Fluorides via η6-Coordination
We developed a Ru/hemilabile-ligand-catalyzed nucleophilic aromatic substitution (SNAr) of aryl fluorides as the limiting reagents. Significant ligand enhancement was demonstrated by the engagement of both electron-rich and neutral arenes in the SNAr amination without using excess arenes. Preliminary mechanistic studies revealed that the nucleophilic substitution proceeds on a η6-complex of the Ru catalyst and the substrate, and the hemilabile ligand facilitates dissociation of products from the metal center.
Kang, Qi-Kai,Li, Yuntong,Lin, Yunzhi,Shi, Hang
supporting information
p. 3706 - 3711
(2020/03/11)

Transition-Metal-Catalyzed Amination of Aryl Fluorides
Arene activation via transition-metal (TM) η 6-coordination has merged as a powerful method to diversify the aromatic C-F bond, which is relatively less reactive due to its high bond energy. However, this strategy in general requires to use largely excess arenes or TM η 6-complexes as the substrates. Herein, we highlight our recent work on the catalytic S NAr amination of electron-rich and electron-neutral aryl fluorides that are inert in classical S NAr reactions. This protocol enabled by a Ru/hemilabile ligand catalyst covers a broad scope of substrates without wasting arenes. Mechanistic studies revealed that the nucleo?-philic substitution proceeded on a Ru η 6-arene complex, and the hemilabile ligand significant promoted the arene dissociation.
Kang, Qi-Kai,Li, Yuntong,Lin, Yunzhi,Shi, Hang
p. 1235 - 1239
(2020/07/20)

METHODS FOR FORMING ARYL CARBON-NITROGEN BONDS USING LIGHT AND PHOTOREACTORS USEFUL FOR CONDUCTING SUCH REACTIONS
The disclosure relates to a method for forming aryl carbon-nitrogen bonds and to photoreactors useful in these and other light-driven reactions. The method comprises contacting an aryl halide with an amine in the presence of a Ni salt catalyst solution and an optional base, thereby forming a reaction mixture; exposing the reaction mixture to light under reaction condition sufficient to produce the aryl carbon-nitrogen bonds. In certain embodiments, the amine may be present in a molar excess to the aryl halide. In certain embodiments, the Ni salt catalyst solution includes a Ni(II) salt and a polar solvent, wherein the Ni(II) salt is dissolved in the polar solvent. In certain embodiments, the reactions conditions include holding the reaction mixture at between about room temperature and about 80° C. for between about 1 hour and about 20 hours such that at least about 50% yield is obtained.
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Paragraph 0097-0098; 0166-0167

(2019/11/22)

Palladate Precatalysts for the Formation of C-N and C-C Bonds
A series of imidazolium-based palladate precatalysts has been synthesized and the catalytic activity of these air- and moisture-stable complexes evaluated as a function of the nature of the imidazolium counterion. These precatalysts can be converted under
Zinser, Caroline M.,Warren, Katie G.,Nahra, Fady,Al-Majid, Abdullah,Barakat, Assem,Islam, Mohammad Shahidul,Nolan, Steven P.,Cazin, Catherine S. J.
p. 2812 - 2817
(2019/08/12)

Direct Installation of a Silyl Linker on Ready-Made NHC Ligands: Immobilized NHC-Pd Complex for Buchwald-Hartwig Amination
An immobilized N-heterocyclic carbene (NHC)-Pd complex was prepared via direct silyl linker installation onto the imidazole backbone of commercially available 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IPr) ligand. The IPr backbone was lithiated and treated with Me2SiCl2 to afford ClMe2Si-IPr, which reacted with [Pd(π-allyl)Cl]2 to yield a ClMe2Si-IPr-Pd complex, and this was immobilized on Wang resin. The immobilized NHC-Pd complex facilitated quantitative Buchwald-Hartwig amination of aryl chlorides within 10 min, even at a low Pd loading of 0.2 mol %. The catalyst could be removed from the reaction mixture by simple filtration, and Pd leaching into the reaction medium was suppressed to below 1 ppm.
Mizusaki, Tomoteru,Matsumoto, Kazuhiro,Takeuchi, Katsuhiko,Fukaya, Norihisa,Takagi, Yukio,Choi, Jun-Chul
supporting information
p. 1872 - 1876
(2019/05/07)

Dihalogen-bridged NHC-palladium(i) dimers: Synthesis, characterisation and applications in cross-coupling reactions
A di-iodo-bridged PdI dimer bearing an N-heterocyclic carbene ligand was made accessible via the reduction of [(IPr)PdI2]2 in basic methanol solution. The structural features of [(IPr)PdI]2 were explored by single-crystal X-ray analysis. It was found to be a convenient one-component precatalyst with high activity in Suzuki-Miyaura, Buchwald-Hartwig, and Sonogashira reactions.
Pirkl, Nico,Del Grosso, Alessandro,Mallick, Bert,Doppiu, Angelino,Goo?en, Lukas J.
supporting information
p. 5275 - 5278
(2019/05/08)

Allyl Palladium Complexes of Cycloheptatrienyl-Cyclopentadienyl Phosphane Ligands in Buchwald-Hartwig Amination Reactions
A series of well-defined palladium allyl chloride pre-catalysts was synthesized using previously reported troticenyl phosphane ligands [(η7-C7H7)Ti(η5-C5H4PR2)] and [(η7-C7H6PR2)Ti(η5-C5H5)] (R = Cy, tBu) as ancillary ligands. The formation of a dimeric μ-chloro-, μ-allyl-bridged PdI species was observed with the ligand [(η7-C7H7)Ti(η5-C5H4PtBu2)], whereas L2Pd0 {L = [(η7-C7H6PtBu2)Ti(η5-C5H5)]} was formed in presence of KOtPent. In addition, the catalytic activity of the palladium allyl chloride pre-catalysts was investigated in Buchwald-Hartwig amination reactions with various aryl halogenides and N-methylaniline or morpholine. The cyclohexyl derivatives show almost no catalytic activity, whereas for the tert-butyl derivatives a significant difference could be observed, depending on whether the seven-membered ring or the five-membered ring is functionalized.
Tr?ndle, Sabrina,Freytag, Matthias,Jones, Peter G.,Tamm, Matthias
supporting information

(2019/04/08)

Palladium nanoparticles supported on cysteine-functionalized MNPs as robust recyclable catalysts for fast O- and N-arylation reactions in green media
A magnetically robust recyclable nanocatalyst was fabricated by immobilizing of Pd onto the surface of cysteine-functionalized magnetic nanoparticles (MNPs?Cys-Pd). This nanocatalyst was characterized using various techniques such as FT-IR, XRD, TEM, SEM, EDX, VSM, and ICP. The application of catalyst (MNPs?Cys-Pd) was investigated for O-arylation and N-arylation reactions. This phosphine-free complex was found as highly efficient heterogeneous catalyst in green media and mild reaction conditions. In addition, it gave excellent recyclability without significant deactivation after ten cycles.
Hajipour, Abdol R.,Khorsandi, Zahra,Fatemeh Mohammadi Metkazini
(2019/08/12)

Energy Transfer to Ni-Amine Complexes in Dual Catalytic, Light-Driven C-N Cross-Coupling Reactions
Dual catalytic light-driven cross-coupling methodologies utilizing a Ni(II) salt with a photocatalyst (PC) have emerged as promising methodologies to forge aryl C-N bonds under mild conditions. The recent discovery that the PC can be omitted and the Ni(II) complex directly photoexcited suggests that the PC may perform energy transfer (EnT) to the Ni(II) complex, a mechanistic possibility that has recently been proposed in other systems across dual Ni photocatalysis. Here, we report the first studies in this field capable of distinguishing EnT from electron transfer (ET), and the results are consistent with F?rster-type EnT from the excited state [Ru(bpy)3]Cl2 PC to Ni-amine complexes. The structure and speciation of Ni-amine complexes that are the proposed EnT acceptors were elucidated by crystallography and spectroscopic binding studies. With the acceptors known, quantitative F?rster theory was utilized to predict the ratio of quenching rate constants upon changing the PC, enabling selection of an organic phenoxazine PC that proved to be more effective in catalyzing C-N cross-coupling reactions with a diverse selection of amines and aryl halides.
Kudisch, Max,Lim, Chern-Hooi,Thordarson, Pall,Miyake, Garret M.
supporting information
p. 19479 - 19486
(2019/12/25)

Practical Catalytic Cleavage of C(sp3)?C(sp3) Bonds in Amines
The selective cleavage of thermodynamically stable C(sp3)?C(sp3) single bonds is rare compared to their ubiquitous formation. Herein, we describe a general methodology for such transformations using homogeneous copper-based catalysts in the presence of air. The utility of this novel methodology is demonstrated for Cα?Cβ bond scission in >70 amines with excellent functional group tolerance. This transformation establishes tertiary amines as a general synthon for amides and provides valuable possibilities for their scalable functionalization in, for example, natural products and bioactive molecules.
Li, Wu,Liu, Weiping,Leonard, David K.,Rabeah, Jabor,Junge, Kathrin,Brückner, Angelika,Beller, Matthias
supporting information
p. 10693 - 10697
(2019/07/09)

Nickel-Catalyzed Decarboxylation of Aryl Carbamates for Converting Phenols into Aromatic Amines
Herein, we describe a new catalytic approach to accessing aromatic amines from an abundant feedstock, namely phenols. The most reliable catalytic method for converting phenols to aromatic amines uses an activating group, such as a trifluoromethane sulfonyl group. However, this activating group is eliminated as a leaving group during the amination process, resulting in significant waste. Our nickel-catalyzed decarboxylation reaction of aryl carbamates forms aromatic amines with carbon dioxide as the only byproduct. As this amination proceeds in the absence of free amines, a range of functionalities, including a formyl group, are compatible. A bisphosphine ligand immobilized on a polystyrene support (PS-DPPBz) is key to the success of this reaction, generating a catalytic species that is significantly more active than simple nonsupported variants.
Nishizawa, Akihiro,Takahira, Tsuyoshi,Yasui, Kosuke,Fujimoto, Hayato,Iwai, Tomohiro,Sawamura, Masaya,Chatani, Naoto,Tobisu, Mamoru
supporting information
p. 7261 - 7265
(2019/05/16)

Late Stage Functionalization of Secondary Amines via a Cobalt-Catalyzed Electrophilic Amination of Organozinc Reagents
A general preparation of polyfunctional hydroxylamine benzoates from the corresponding secondary amines is reported. This convenient synthesis allows the setup of a late-stage functionalization of various secondary amines, including pharmaceuticals and peptidic derivatives. Thus, a cross-coupling of hydroxylamine benzoates with various alkyl-, aryl-, and heteroaryl-zinc chlorides in the presence of 5 mol % CoCl2 (25 °C, 2 h) provides a range of polyfunctional tertiary amines. This method was used to prepare penfluridol and gepirone.
Gra?l, Simon,Chen, Yi-Hung,Hamze, Clémence,Tüllmann, Carl Phillip,Knochel, Paul
supporting information
p. 494 - 497
(2019/01/14)

Synergistic Ligand Effect between N-Heterocyclic Carbene (NHC) and Bicyclic Phosphoramidite (Briphos) Ligands in Pd-Catalyzed Amination
A synergistic ligand effect between NHC and phosphorus ligands in Pd-catalyzed Buchwald-Hartwig amination reactions was demonstrated with tunable π-acceptor bicyclic bridgehead phosphoramidite (briphos) ligands. The catalytic activity of NHC-Pd-L (L = phosphorus ligand) precatalysts depends on the electronic properties of L. A NHC-Pd-L catalyst with an N-cyclohexyl-substituted briphos ligand was found to be highly efficient. A series of C-N bond coupling reactions between primary or secondary amines and aryl chlorides were performed with high yields under mild reaction conditions.
Kim, Miji,Shin, Taeil,Lee, Ansoo,Kim, Hyunwoo
supporting information
p. 3253 - 3258
(2018/10/02)

An Effective Heterogeneous Copper Catalyst System for C-N Coupling and Its Application in the Preparation of 2-Methyl-4-methoxydiphenylamine (MMDPA)
A ligand-recyclable, environmentally benign heterogeneous catalyst system composed of CuI and polystyrene-supported N (-(4-(aminomethyl)naphthalen-1-yl)- N (-phenyl-1 H -pyrrole-2-carbohydrazide (PSAP) has been established for Ullmann type C-N coupling based on the homogeneous catalyst system N ′, N ′-diphenyl-1 H -pyrrole-2-carbohydrazide/CuI. This heterogeneous catalyst system maintained the catalytic effectiveness of the homogeneous catalyst. A variety of functionalized aryl bromides can be efficiently aminated with aryl amines and aliphatic amines with high selectivity for amines over alcohols. Moreover, a practical application of this catalyst system to promote the reaction of commercially available 4-methoxy-2-methylaniline and bromobenzene in 10 mmol scale, provided 2-methyl-4-methoxydiphenylamine (MMDPA) with 93% yield with the merit of the approach being simple operation for work-up and purification.
Yi, Zhou,Huang, Manna,Wan, Yiqian,Zhu, Xinhai
p. 3911 - 3920
(2018/09/29)

Buchwald-Hartwig amination reaction of aryl halides using heterogeneous catalyst based on Pd nanoparticles decorated on chitosan functionalized graphene oxide
In this work, graphene oxide was functionalized with chitosan (GO-Chit) followed by a simple approach for immobilization of palladium nanoparticles onto a chitosan grafted graphene oxide surface. The Pd-nanocomposite (GO-Chit-Pd) was characterized using Transmission Electron Microscopy (TEM), Fourier transforms infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) measurements. The catalytic activity of the prepared heterogeneous graphene oxide functionalized chitosan-palladium (GO-Chit-Pd) was investigated in term of C-N coupling reaction (Buchwald-Hartwig amination reaction of aryl halides) yielding products of N-arylamines. The easy purification, convenient operation, and environmental friendliness, combined with a high yield, render this method viable for use in both laboratory research and larger industrial scales. Studying the reusability of the catalyst in this work showed that it could be reused for five times without obvious loss in catalytic activity.
Sarvestani, Mosayeb,Azadi, Roya
(2017/10/05)

Palladium(II) anchored on polydopamine coated-magnetic nanoparticles (Fe3O4&at;PDA&at;Pd(II)): A heterogeneous and core–shell nanocatalyst in Buchwald–Hartwig C–N cross coupling reactions
An efficient method was proposed to synthesize polydopamine (PDA)-coated Fe3O4 nanoparticles (Fe3O4&at;PDA). For the first time, effective deposition of Pd complex is explained by using Fe3O4&at;PDA as a core–shell magnetic coordinator and stabilizer agent. In this method, palladium ions were adsorbed on Fe3O4&at;PDA surfaces through immersion of the Fe3O4&at;PDA into a palladium plating bath. The structure, morphology and physicochemical features of the prepared particles were studied using various analytical methods including high resolution transmission electron microscopy (HR-TEM), field emission scanning electron microscope (FESEM), energy-dispersive X-ray spectroscopy (EDS), vibrating sample magnetometer (VSM), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP), thermogravimetric analysis (TGA) and FT-IR spectroscopy. Core–shell Fe3O4&at;PDA/Pd(II) nanoparticles showed excellent catalytic performance as a reusable nanocatalyst in Pd-catalyzed Buchwald–Hartwig C–N cross coupling reaction. A variety of aryl amines were prepared through reaction of aryl halides (chloride, bromide and iodide) and amines in high yields. The catalyst can be recycled and reapplied up to six cycles with no considerable change in its catalytic activity.
Hemmati, Saba,Sarachegol, Pegah,Veisi, Hojat
p. 64 - 71
(2018/10/04)

[Pd(IPr*R)(acac)Cl]: Efficient bulky Pd-NHC catalyst for Buchwald-Hartwig C-N cross-coupling reaction
A series of bulky palladium catalysts based on N-heterocyclic carbene, (Pd(NHC)(acac)Cl: NHC = IPr*me = N,N′-bis(2,6-bis(di-p-tolylmethyl)-4-methylphenyl)-imidazol-2 -ylidene, Pd(IPr*me)(acac)Cl; NHC = IPr*ipr = N,N′-bis(2,6-bis(di-4-isopropylphenyl)-4-methylphenyl)-imidazol-2 -ylidene, Pd(IPr*ipr)(acac)Cl; and NHC = IPr*tBu = N,N′-bis(2,6-bis(di-4-(tert-butyl)phenyl)- 4-methylphenyl)- imidazol-2-ylidene, Pd(IPr*tBu)(acac)Cl; acac = acetylacetonate), have been designed and synthesized. These three new catalysts showed much better catalytic activity in the Buchwald?Hartwig arylamination coupling reaction as compare to the earlier congener (IPr*)Pd(acac)Cl (IPr* = N,N′-bis(2,6-diphenylmethyl)-4-methylphenylimidazol-2-ylidene). The highly active PdII precatalyst [Pd(IPr*me)(acac)Cl] has been fully explored by using a wide range of substrates with different electronic and steric demands of coupling partners, for which up to 99% isolated yields were obtained. Remarkably, the moderate isolated yield was obtained for the challenging coupling of the amine bearing very bulky groups.
Tian, Xiabing,Lin, Jing,Zou, Sheng,Lv, Junwei,Huang, Qingfei,Zhu, Jin,Huang, Shuping,Wang, Qiwei
supporting information
p. 125 - 130
(2018/03/06)

C-N Cross-Coupling via Photoexcitation of Nickel-Amine Complexes
C-N cross-coupling is an important class of reactions with far-reaching impacts across chemistry, materials science, biology, and medicine. Transition metal complexes can elegantly orchestrate diverse aminations but typically require demanding reaction conditions, precious metal catalysts, or oxygen-sensitive procedures. Here, we introduce a mild nickel-catalyzed C-N cross-coupling methodology that operates at room temperature using an inexpensive nickel source (NiBr2·3H2O), is oxygen tolerant, and proceeds through direct irradiation of the nickel-amine complex. This operationally robust process was employed for the synthesis of diverse C-N-coupled products (40 examples) by irradiating a solution containing an amine, an aryl halide, and a catalytic amount of NiBr2·3H2O with a commercially available 365 nm LED at room temperature without added photoredox catalyst and the amine substrate serving additional roles as the ligands and base. Density functional theory calculations and kinetic isotope effect experiments were performed to elucidate the observed C-N cross-coupling reactivity.
Lim, Chern-Hooi,Kudisch, Max,Liu, Bin,Miyake, Garret M.
supporting information
p. 7667 - 7673
(2018/05/31)

Ultrafine hybrid Cu2O-Fe2O3 nanoparticles stabilized by hexaphenylbenzene-based supramolecular assemblies: A photocatalytic system for the Ullmann-Goldberg coupling reaction
Ultrafine hybrid Cu2O-Fe2O3 NPs have been prepared using the supramolecular assemblies of hexaphenylbenzene (HPB) derivative 3 as nanoreactors and stabilizers. The as-prepared hybrid Cu2O-Fe2O3 NPs serve as an efficient and recyclable photocatalytic system for carrying out C-N coupling between aryl halides and various amines (aliphatic, aromatic and N-heterocyclic) at room temperature in mixed aqueous media under visible light irradiation. Amazingly, Cu2O-Fe2O3 NPs also exhibited high efficiency in the reactions involving the synthesis of biologically important N-substituted carbazole derivatives. The work being presented in this article demonstrates the preparation of a 'dip strip' coated with the as-prepared catalytic system and utilization of this paper strip as a recyclable and portable heterocatalytic system for carrying out the Ullmann-Goldberg coupling.
Singh, Gurpreet,Kumar, Manoj,Bhalla, Vandana
p. 5346 - 5357
(2018/12/05)

Cobalt-Catalyzed Electrophilic Amination of Aryl- and Heteroarylzinc Pivalates with N-Hydroxylamine Benzoates
Aryl- and heteroarylzinc pivalates can be aminated with O-benzoylhydroxylamines at 25 °C within 2–4 h in the presence of 2.5–5.0 % CoCl2?2 LiCl to furnish the corresponding tertiary arylated or heteroarylated amines in good yields. This electrophilic amination also provides access to diarylamines and aryl(heteroaryl)amines. A new tuberculosis drug candidate (Q203) was prepared in six steps and 56 % overall yield by using this cobalt-catalyzed amination as the key step.
Chen, Yi-Hung,Gra?l, Simon,Knochel, Paul
p. 1108 - 1111
(2018/01/01)

Heteroleptic (N-heterocyclic carbene)–Pd–pyrazole (indazole) complexes: Synthesis, characterization and catalytic activities towards C–C and C–N cross-coupling reactions
Eight heteroleptic palladium complexes containing both N-heterocyclic carbenes and NH-heterocycle azoles (pyrazole and indazole) were synthesized and characterized, and their structures were unambiguously confirmed using single-crystal X-ray diffraction. Further investigation of the complexes as catalysts in the Suzuki–Miyaura reaction and Buchwald–Hartwig amination revealed good reactivities for aryl chlorides.
Yang, Jin
(2017/09/26)

Synthesis of 3-Arylbenzofuran-2-ylphosphines via Rhodium-Catalyzed Redox-Neutral C-H Activation and Their Applications in Palladium-Catalyzed Cross-Coupling of Aryl Chlorides
A new class of aryl-heteroarylphosphines, 3-arylbenzofuran-2-ylphosphines, was synthesized by [Cp?Rh(III)]-catalyzed redox-neutral cyclization of N-phenoxyacetamides with 1-alkynylphosphine sulfides and oxides followed by reduction. This step-economic reaction proceeds in excellent regioselectivity with a broad substrate scope. The application of the resulting air-stable trivalent-phosphine containing dicyclohexylphosphino moiety in palladium-catalyzed Suzuki-Miyaura coupling and Buchwald-Hartwig amination of aryl chlorides is also described.
Wang, Huanan,Wang, Baiquan,Li, Bin
p. 9560 - 9569
(2017/09/23)

The invention relates to a N, N - disubstituted hydrazide as ligand copper catalysis C - N coupling method (by machine translation)
The invention discloses a to N, N - disubstituted hydrazide as ligand copper catalysis C - N coupling method, the method uses the aromatic halides with amine compound as a raw material, in order to alcohol compound as the solvent, in order to copper or copper compound as a catalyst, in order to as formula I or formula II as shown by a N, N - disubstituted hydrazide as a ligand, the presence of a base, in the 10 - 130 °C generating C - N coupled reaction for generating N - aryl compound: the invention mild reaction conditions, high chemical selectivity, substrate and wide range of application, simplicity of operation, product is simple and easy to separation and environmental protection, the obtained product yield is higher. Wherein R1, R2 is selected from methyl, phenyl, 4 - methoxyphenyl, 4 - nitro-phenyl, 2 - methylphenyl, 2 - isopropyl phenyl; R3 is hydrogen or methoxy. (by machine translation)
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Paragraph 0063-0065

(2017/07/21)

Room-Temperature CuI-Catalyzed Amination of Aryl Iodides and Aryl Bromides
A general and effective CuI/N′,N′-diaryl-1H-pyrrole-2-carbohydrazide catalyst system was developed for the amination of aryl iodides and bromides at room temperature with good chemoselectivity between -OH and -NH2 groups. Only 5 mol % of CuI and ligands was needed in this protocol to effect the amination of various aryl bromides and aryl iodides with a wide range of aliphatic and aryl amines (1.3 equiv).
Ding, Xiaomei,Huang, Manna,Yi, Zhou,Du, Dongchen,Zhu, Xinhai,Wan, Yiqian
p. 5416 - 5423
(2017/05/25)

Making Copper(0) Nanoparticles in Glycerol: A Straightforward Synthesis for a Multipurpose Catalyst
Small zero-valent copper nanoparticles (CuNPs) have been straightforwardly prepared from Cu(I) and Cu(II) precursors in glycerol and in the presence of polyvinylpyrrolidone as stabilizer. Thanks to the negligible vapor pressure of the solvent, these original nano-systems could be directly characterized in glycerol as well as in the solid state, exhibiting relevantly homogeneous colloidal dispersions, also even after catalysis. CuNPs coming from the well-defined coordination complex di-μ-hydroxobis[(N,N,N′,N′-tetramethylethylenediamine)copper(II)] chloride {[Cu(κ2-N,N-TMEDA)(μ-OH)]2Cl2} have been highly efficient in C–C and C–heteroatom bond formation processes. This new catalytic system has proved its performance in C–N couplings and in the synthesis of differently substituted propargylic amines through cross-dehydrogenative couplings, multi-component reactions such as A3 (aldehyde-alkyne-amine) and KA2 (ketone-alkyne-amine) couplings, as well as in the formation of heterocycles such as benzofurans, indolizines, and quinolines under smooth conditions. No significant copper amount was detected in the extracted organic compounds from the catalytic phase by inductively coupled plasma-atomic emission spectroscopic (ICP-AES) analyses, proving a highly efficient immobilization of copper nanoparticles in glycerol. From a mechanistic point of view, spectroscopic data (infrared and ultraviolet-visible spectra) agree with a surface-like catalytic reactivity. (Figure presented.).
Dang-Bao, Trung,Pradel, Christian,Favier, Isabelle,Gómez, Montserrat
p. 2832 - 2846
(2017/08/23)

Nickel-Catalyzed Amination of Aryl 2-Pyridyl Ethers via Cleavage of the Carbon-Oxygen Bond
Reaction of aryl 2-pyridyl ethers with amines was carried out via Ni-catalyzed C-OPy bond cleavage, giving aniline derivatives in reasonable to excellent yields. Both electron-rich and electron-poor aryl 2-pyridyl ethers and a wide range of amines can be used in the transformation. The method provides a conversion way for the 2-pyridyloxy directing group in the C-H bond functionalization reactions.
Li, Jing,Wang, Zhong-Xia
supporting information
p. 3723 - 3726
(2017/07/26)

Preparation method of novel bidentate phosphite ligand and application thereof in Buchwald-Hartwig reaction
The invention discloses a preparation method of novel bidentate phosphite ligands and application thereof in Buchwald-Hartwig reaction and belongs to the field of organic synthetic chemistry. A series of novel bidentate phosphite ligands are synthesized by using 3,3',5,5'-tetra-tert-butyl-2,2'-dihydroxyl diphenyl and glycols with different structures as raw materials through a two-step one-pot method, are compounds very wide in application range and have the following structures. The novel preparation method has the advantages of being stable in structure, simple and convenient to synthesize, high in yield and easy to prepare in a large-scale mode. The ligands have higher reaction activity and substrate universality in the Pd catalyzed Buchwald-Hartwig reaction.
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Paragraph 0050; 0051; 0052; 0053; 0054; 0057; 0058; 0060-64

(2016/10/09)

Synthesis and characterization of N-heterocyclic carbene-palladium(II) chlorides-1-methylindazole and -1-methylpyrazole complexes and their catalytic activity toward C-N coupling of aryl chlorides
A series of N-heterocyclic carbene-palladium(ii) chlorides-1-methylindazole and -1-methylpyrazole complexes was successfully synthesized and fully characterized by X-ray single crystal diffraction. In addition, initial investigations of their catalytic activity showed that they were efficient catalysts in the C-N coupling of primary and secondary amines with aryl chlorides at low catalyst loadings.
Zhao, Xiao-Yun,Zhou, Quan,Lu, Jian-Mei
p. 24484 - 24490
(2016/03/15)