- Titanium-Catalyzed Hydroaminoalkylation of Ethylene
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The first examples of titanium-catalyzed hydroaminoalkylation reactions of ethylene with secondary amines are presented. The reactions can be achieved with various titanium catalysts and they do not require the use of high pressure equipment. In addition, the first solid-state structure of a titanapyrrolidine that is formed by insertion of an alkene into the Ti?C bond of a titanaaziridine is reported.
- Rosien, Michael,T?ben, Iris,Schmidtmann, Marc,Beckhaus, Rüdiger,Doye, Sven
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supporting information
p. 2138 - 2142
(2020/02/05)
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- Practical and regioselective amination of arenes using alkyl amines
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The formation of carbon–nitrogen bonds for the preparation of aromatic amines is among the top five reactions carried out globally for the production of high-value materials, ranging from from bulk chemicals to pharmaceuticals and polymers. As a result of this ubiquity and diversity, methods for their preparation impact the full spectrum of chemical syntheses in academia and industry. In general, these molecules are assembled through the stepwise introduction of a reactivity handle in place of an aromatic C–H bond (that is, a nitro group, halogen or boronic acid) and a subsequent functionalization or cross-coupling. Here we show that aromatic amines can be constructed by direct reaction of arenes and alkyl amines using photocatalysis, without the need for pre-functionalization. The process enables the easy preparation of advanced building blocks, tolerates a broad range of functionalities, and multigram scale can be achieved via a batch-to-flow protocol. The merit of this strategy as a late-stage functionalization platform has been demonstrated by the modification of several drugs, agrochemicals, peptides, chiral catalysts, polymers and organometallic complexes.
- Ruffoni, Alessandro,Juliá, Fabio,Svejstrup, Thomas D.,McMillan, Alastair J.,Douglas, James J.,Leonori, Daniele
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p. 426 - 433
(2019/05/01)
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- A Highly Active PN3 Manganese Pincer Complex Performing N-Alkylation of Amines under Mild Conditions
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A highly active Mn(I) catalyst based on a nonsymmetric PN3-ligand scaffold for the N-alkylation of amines with alcohols utilizing the borrowing hydrogen methodology is reported. A broad range of anilines and the more challenging aliphatic amines were alkylated with primary and secondary alcohols. Moreover, the combination of low catalyst loadings and mild reaction conditions provides high efficiency for this atom-economic transformation.
- Homberg, Leonard,Roller, Alexander,Hultzsch, Kai C.
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supporting information
(2019/05/07)
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- Solvent-free mechanochemical Buchwald-Hartwig amination of aryl chlorides without inert gas protection
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A solvent-free Buchwald-Hartwig amination had been developed under high-speed ball-milling conditions, which afforded the desired products with moderate to high yields. The addition of sodium sulfate was found to be crucial for improving both the performance and the reproducibility. Comparative solvent-free stirring experiments implicated the importance of mechanical interaction for the transformation, and the inert gas was proved to be unnecessary for this amination.
- Shao, Qiao-Ling,Jiang, Zhi-Jiang,Su, Wei-Ke
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supporting information
p. 2277 - 2280
(2018/05/16)
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- N-Alkylation of Aniline and Its Derivatives by Alcohols in the Presence of Copper Compounds
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N-Alkyl- and N,N-dialkyl-substituted anilines were obtained in the reaction of aniline and its derivatives with primary and secondary alcohols in the presence of catalysts CuCl2·2H2O, CuBr2 and halomethanes as promoters.
- Bayguzina,Musina, Ch. F.,Khusnutdinov
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p. 1652 - 1659
(2019/02/12)
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- AQUEOUS RESIN BASED INKJET INKS
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An inkjet ink includes a) an aqueous medium; and b) capsules composed of a polymeric shell surrounding a core; wherein the capsules are dispersed in the aqueous medium using a dispersing group covalently bonded to the polymeric shell; the core contains on
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Paragraph 0229
(2017/02/28)
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- Electrophilic Amination with Nitroarenes
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An exceptionally general electrophilic amination, which directly transforms commercially available nitroarenes into alkylated aromatic aminoboranes with zinc organyl compounds was developed. The reaction starts with a two-step partial reduction of the nitro group to a nitrenoid, which is used in situ as the electrophilic amination reagent. To facilitate isolation, the resulting air- and moisture-sensitive aminoboranes were reacted with a range of electrophiles. The method not only represents a direct transformation of nitro compounds into electrophilic amination reagents but also provides an elegant alternative to dehydrocoupling methods for the generation of aminoboranes.
- Rauser, Marian,Ascheberg, Christoph,Niggemann, Meike
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supporting information
p. 11570 - 11574
(2017/09/11)
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- Cu2O/nano-CuFe2O4: An efficient and magnetically recoverable catalyst for the ligand-free N-arylation of amines and nitrogen heterocycles with aryl halides
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An efficient strategy has been developed for the N-arylation of azoles and aliphatic amines with aryl halide using a Cu2O/nano-CuFe2O4 magnetic composite as the catalyst and KOH as the base. The methodology is found to be applicable to a variety of nitrogen-containing heterocycles, such as imidazole, indole, and pyrrole, as well as aliphatic amines in high yields with practical simplicity under cost-effective "ligand-free" conditions. The magnetic property of the catalyst allowed its fast separation from the reaction medium by an external magnet. Additionally, the inexpensive catalyst could be recycled for five consecutive runs with small drops in catalytic activity.
- Elhampour, Ali,Nemati, Firouzeh,Kaveh, Mahdieh
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supporting information
p. 223 - 225
(2016/03/01)
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- Cobalt-Catalyzed Synthesis of Aromatic, Aliphatic, and Cyclic Secondary Amines via a "hydrogen-Borrowing" Strategy
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The replacement of precious metals with inexpensive, less toxic, and earth-abundant elements in typical noble-metal-mediated organic transformations is a major goal in current synthetic chemistry and industries. The metal-catalyzed N-alkylation of amines with other amines through a "hydrogen-borrowing" principle represents a green and atom-economical reaction for the synthesis of secondary amines. However, catalysts developed thus far that are effective for this process remain quite scarce and are only limited to a few ruthenium and iridium complexes. In this work, we present a cobalt-catalyzed selective alkylation of amines with amines to synthesize a large variety of secondary amines. A range of amine substrates have been converted to the corresponding products through hetero- or homocoupling between amines. Cyclic sec-amines are also achieved from diamine precursors as rare examples.
- Yin, Zhiwei,Zeng, Haisu,Wu, Jing,Zheng, Shengping,Zhang, Guoqi
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p. 6546 - 6550
(2016/10/14)
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- Magnetic nanoparticle-supported phosphine gold(i) complex: A highly efficient and recyclable catalyst for the direct reductive amination of aldehydes and ketones
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The direct reductive amination of aldehydes and ketones has been achieved in dichloromethane at room temperature by using a magnetic nanoparticle-supported phosphine gold(i) complex [Fe3O4@SiO2-P-AuCl] as the catalyst and ethyl Hantzsch ester as the hydrogen source, yielding a variety of secondary amines in excellent yields under neutral conditions. The new heterogeneous gold catalyst can be prepared by a simple procedure from commercially readily available reagents and can easily be separated from the reaction mixture by applying an external magnet and recycled at least 10 times without any loss of activity.
- Yang, Weisen,Wei, Li,Yi, Feiyan,Cai, Mingzhong
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p. 4554 - 4564
(2016/07/06)
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- Disperse dye mixture, containing the dye composition and method using the same
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PROBLEM TO BE SOLVED: To provide a disperse dye mixture having excellent color reproducibility in a wide color reproduction range, particularly in a hue range of blue-cyan-green-yellow when used for text printing.SOLUTION: The dye mixture contains at leas
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Paragraph 0067
(2016/12/22)
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- Facile and efficient reductive N-alkylation of nitrobenzenes with alcohols catalyzed by Cu-Cr/γ-Al2O3
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A facile and efficient method for reductive N-alkylation of nitrobenzenes with alcohols catalyzed by the bimetallic catalyst Cu30Cr5/γ-Al2O3, in a fixed-bed reactor, was successfully established. X-ray diffraction, temperature-programmed reduction, and X-ray photoelectron spectroscopy were used to characterize the catalyst. Introduction of Cr to Cu30/γ-Al2O3 was found to substantially enhance the dispersion of Cu0 particles, which are believed to be the active sites for the reductive N-alkylation. The reaction conditions were optimized and a series of alcohols and nitrobenzenes were converted into N-alkylated anilines in more than 90 % yield by use of this catalyst.
- Song, Ge,Tian, Jun,Chen, Ligong,Li, Yang
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p. 5399 - 5409
(2015/07/08)
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- Palladium-catalyzed amination of aryl sulfides with aliphatic amines
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Conditions for the palladium-NHC-catalyzed amination of aryl sulfides with aliphatic as well as aromatic amines were established. The KHMDS-mediated amination of heteroaryl sulfides could proceed without palladium. Based on the distinct difference in reactivity of C-Br and C-S bonds, a sequential amination of bromothioanisole can take place to install two different alkylamino groups onto the aromatic ring in one pot. A palladium-NHC precatalyst shows high efficiency for C-S bond cleavage for the amination of aryl sulfides with aliphatic amines or aromatic amines.
- Gao, Ke,Yorimitsu, Hideki,Osuka, Atsuhiro
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supporting information
p. 2678 - 2682
(2015/04/27)
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- Chemoselective reductive amination of carbonyl compounds for the synthesis of tertiary amines using SnCl2·2H2O/PMHS/MeOH
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Stannous chloride catalyzed chemoselective reductive amination of a variety of carbonyl compounds with aromatic amines has been developed for the synthesis of a diverse range of tertiary amines using inexpensive polymethylhydrosiloxane as reducing agent in methanol. The present method is also applicable for the synthesis of secondary amines including heterocyclic ones.
- Nayal, Onkar S.,Bhatt, Vinod,Sharma, Sushila,Kumar, Neeraj
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p. 5912 - 5918
(2015/06/16)
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- Design of a bifunctional Ir-Zr based metal-organic framework heterogeneous catalyst for the N-alkylation of amines with alcohols
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The direct N-alkylation of amines with alcohols was performed with an Ir-Zr-based metal-organic framework multifunctional heterogeneous catalyst. This system is efficient and environmentally benign for the synthesis of various organic amines in air in the absence of a base. The catalyst was recovered and reused without significant loss of activity, and only water was produced as a byproduct. Better be direct than elusive: The direct N-alkylation of amines with alcohols is performed with an Ir-Zr-based metal-organic framework multifunctional heterogeneous catalyst. This system is efficient and environmentally benign for the synthesis of various organic amines in air in the absence of a base. The catalyst is recovered and reused without significant loss of activity, and only water is produced as a byproduct.
- Rasero-Almansa,Corma,Iglesias,Sanchez
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p. 1794 - 1800
(2014/06/24)
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- Ligand-free C-N bond formation in aqueous medium using a reusable Cu-Mn bimetallic catalyst
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A general ligand-free protocol has been described for the recyclable and reusable Cu-Mn catalyzed C-N bond forming cross coupling reaction of arylboronic acids with various amines to form N-arylated amine products in aqueous medium affording excellent yields under ambient conditions, in 3-4 h.
- Sawant, Sanghapal D.,Srinivas, Mahesuni,Aravinda Kumar,Lakshma Reddy,Singh, Parvinder Pal,Singh, Baldev,Sharma, Amit Kumar,Sharma,Vishwakarma, Ram A.
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p. 5351 - 5354
(2013/09/12)
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- Use of primary amines for the selective n-alkylation of anilines by a reusable heterogeneous catalyst
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Traditionally, anilines can be alkylated with reactive alkyl halides but now more safe reagents such as alcohols or even amines can be used. To overcome the limits of homogeneous catalysis for aniline N-alkylation, we have developed a protocol that employs simple Pd/C as a heterogeneous catalyst under microwave dielectric heating. The process, based on the easy Pd-mediated oxidation of primary amines to imines followed by aniline addition, is characterized by a high atom economy as ammonia is the only other product of the reaction. This kind of aniline alkylation with amines has been carried out both in ionic liquid medium using [bmim]PF6 or in a more traditional solvent such as THF where the catalyst could be successfully recycled more times. The reusability of the catalyst was further confirmed by using material recycled from the amination in a standard alkene hydrogenation without loss of efficiency. Georg Thieme Verlag Stuttgart New York.
- Linciano, Pasquale,Pizzetti, Marianna,Porcheddu, Andrea,Taddei, Maurizio
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p. 2249 - 2254
(2013/11/06)
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- Intermolecular rhodium-catalysed hydroamination of non-activated olefins: Effect of olefin, amine, phosphine and phosphonium salt
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The catalytic system RhCl3·3H2O/2P(p-CH3C6H4)3/65nBu4PI/2I2, which was discovered recently in our research group, allows the highest catalytic activity ever reported for the intermolecular hydroamination of ethylene, 1-butene, and 1-hexene with aniline-type amines (0.3 mol% catalytic precursor) to give the expected N-alkyl- (N-ethyl-, 1) and N,N-dialkyl-anilines (N,N-diethyl-, 2) along with 2-methyl quinolines (3; in the case of ethylene). The effects of time and temperature, as well as the nature of the phosphonium salt, phosphine, and amine on the catalytic activity of this reaction have been studied. This system is particularly efficient for the hydroamination of ethylene with aniline in the presence of 2,2′-bis(diphenylphosphino)- 1,1′-binaphthyl (CE=460) and tri(p-tolyl)phosphine (CE= 520). Good to excellent activities were also found by combining Wilkinson′s catalysts (RhI complexes) with nBu4PI and I2. The simple association of PPh3 and I2 has been shown to be a very efficient "in-situ generated" source of I- promoters. CE (catalytic efficiency)=TON1+2TON2+2TON3.
- Rodriguez-Zubiri, Mireia,Baudequin, Christine,Bethegnies, Aurelien,Brunet, Jean-Jacques
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p. 445 - 454
(2014/01/17)
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- Transition-metal-free electrophilic amination of arylboroxines
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A transition-metal-free strategy to construct C(sp2)-N bonds using arylboroxines and O-benzoyl hydroxylamines as coupling partners has been developed. This transformation provides a useful method to access various aromatic amines.
- Xiao, Qing,Tian, Leiming,Tan, Renchang,Xia, Ying,Qiu, Di,Zhang, Yan,Wang, Jianbo
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p. 4230 - 4233
(2012/09/22)
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- Sulfur promoted Pt/SiO2 catalyzed cross-coupling of anilines and amines
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Pt/SiO2 (Pt = 5 wt%) catalysts with average Pt particle size of 3.3 and 6.8 nm and sulfur-loaded Pt/SiO2 (S/Pt ratio = 0.1 and 0.13; Pt size = 5.2 and 5.5 nm), prepared by adding ammonium sulfate on Pt/SiO 2 followed by H2-reduction at 500 °C, are tested for mono-N-alkylation of aniline with di-iso-propylamine. The turnover frequency (TOF), defined as the reaction rate per number of surface Pt species, increases with sulfur loading. The catalyst with S/Pt ratio of 0.13 shows more than 5 times higher TOF than unmodified catalysts, and it acts as effective and recyclable catalyst for cross-coupling of various anilines and amines. Combined with kinetic results and characterizations, XAFS (X-ray absorption fine structure), TEM, and CO adsorption IR, a possible reason for the promotion effect of sulfur species (probably sulfidic species) is discussed.
- Shimizu, Ken-Ichi,Shimura, Katsuya,Tamagawa, Naoko,Tamura, Masazumi,Satsuma, Atsushi
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scheme or table
p. 37 - 42
(2012/04/23)
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- Carbon dioxide-promoted selective reductive amination of aliphatic ketones with aniline and hydrogen using a Pt/C catalyst
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Product selectivity in the reductive amination of aliphatic ketones with aniline and H2 using a 5% Pt/C catalyst was improved remarkably in the presence of CO2. The CO formed in situ by the reverse watergas shift reaction selectively poisoned the Pt sites active for undesired side reactions.
- Ichikawa, Shinichiro,Seki, Tsunetake,Ikariya, Takao
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supporting information
p. 1628 - 1629
(2013/03/28)
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- Reductive amination of carbonyl compounds over silica supported palladium exchanged molybdophosphoric acid catalysts
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Palladium exchanged molybdophosphoric acid supported on silica is reported as a highly effective catalyst for direct reductive amination of carbonyl compounds. The catalysts are characterized by X-ray diffraction and FT-infrared spectroscopy. The characterization results support the existence of Keggin ion of heteropoly molybdate on silica. The catalyst is facile, water tolerable and environmentally benign for reductive amination. A variety of secondary and tertiary amines can be synthesized over this catalyst in excellent yields under mild reaction conditions. A plausible reaction mechanism is proposed for the reductive amination of carbonyl compounds over this catalyst.
- Srivani,Prasad, P. S. Sai,Lingaiah
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experimental part
p. 389 - 396
(2012/06/18)
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- Titanium-mediated amination of Grignard reagents using primary and secondary amines
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Make it, then break it: N-chlorosuccinimide (NCS) was employed as the oxidant in the synthesis of aniline derivatives using the title transformation (see scheme). Functionalization was well tolerated on both the amine and Grignard reagent. An androgen receptor agonist and several analogues were synthesized to demonstrate the utility of this method.
- Barker, Timothy J.,Jarvo, Elizabeth R.
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supporting information; experimental part
p. 8325 - 8328
(2011/10/31)
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- Direct reductive amination of aromatic aldehydes catalyzed by gold(i) complex under transfer hydrogenation conditions
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The direct reductive amination of aromatic aldehydes has been achieved with excellent isolated yields (89-96%) using readily accessible Ph 3PAuCl/AgOTf catalyst along with ethyl Hantzsch ester as hydrogen source under mild reaction conditions.
- Zhang, Ming,Yang, Hongwei,Zhang, Yan,Zhu, Chengjian,Li, Wei,Cheng, Yixiang,Hu, Hongwen
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supporting information; experimental part
p. 6605 - 6607
(2011/07/08)
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- Zinc-promoted, iridium catalyzed reductive alkylation of primary amines with aliphatic ketones in aqueous medium
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The reductive alkylation of primary aromatic and aliphatic amines with aliphatic ketones has been achieved in aqueous acidic medium using commercially available, non-activated zinc dust catalyzed by a very small quantity of iridium bromide. Anilines react well in aqueous formic acid, whereas monoalkylamines require 1,4-dioxane as a co-solvent and sulfuric acid as the proton source. A plausible mechanism via low-valent iridium hydride species is proposed.
- da Silva, Renato A.,Bieber, Lothar W.
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scheme or table
p. 689 - 691
(2010/04/02)
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- Palladium-catalyzed amination of aryl and heteroaryl tosylates at room temperature
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Mild palladium-catalyzed aminations of aryl tosylates and the first aminations of heteroaryl tosylates are described. In the presence of the combination of L2Pd(0) (L = P(o-tol)3) and the hindered Josiphos ligand CyPF-t-Bu, a variety of primary alkylamines and arylamines react with both aryl and heteroaryl tosylates at room temperature to form the corresponding secondary arylamines in high yields with complete selectivity for the monoarylamine. These reactions at room temperature occur in many cases with catalyst loadings of 0.1 mol % and 0.01 mol % in one case, constituting the most efficient aminations of aryl tosylates by nearly 2 orders of magnitude. This catalyst is made practical by the development of a convenient method to synthesize the L2Pd(0) precursor. This complex is stable to air as a solid. In contrast to conventional relative rates for reactions of aryl sulfonates, the reactions of aryl tosylates are faster than parallel reactions of aryl triflates, and the reactions of aryl tosylates are faster than parallel or competitive reactions of aryl chlorides. Copyright
- Ogata, Tokutaro,Hartwig, John F.
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supporting information; experimental part
p. 13848 - 13849
(2009/02/07)
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- Direct reductive amination of carbonyl compounds with primary/secondary amines using recyclable water-soluble FeII/EDTA complex as catalyst
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Direct reductive amination of aliphatic, aromatic and heterocyclic carbonyl compounds with primary/secondary amines is reported with water-soluble FeII/EDTA complex as a catalyst using low-pressure molecular hydrogen in a biphasic media. The catalyst is highly selective, recyclable and is an excellent replacement for expensive noble metal catalysts or stoichiometric reducing agents.
- Bhor, Malhari D.,Bhanushali, Mayur J.,Nandurkar, Nitin S.,Bhanage, Bhalchandra M.
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p. 965 - 969
(2008/09/17)
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- Direct reductive amination of carbonyl compounds using bis(triphenylphosphine) copper(I) tetrahydroborate
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A direct reductive amination protocol for aldehydes/ketones using bis(triphenylphosphine) copper(I) tetrahydroborate as a novel reducing agent in the presence of sulfamic acid has been developed. The reagent chemoselectively reduces the imine moiety and does not affect other reducible functionalities such as chloro, nitro, cyano and methoxy.
- Bhanushali, Mayur J.,Nandurkar, Nitin S.,Bhor, Malhari D.,Bhanage, Bhalchandra M.
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p. 1273 - 1276
(2007/10/03)
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- Highly efficient and practical phosphoramidite-copper catalysts for amination of aryl iodides and heteroaryl bromides with alkylamines and N(H)-heterocycles
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A highly efficient copper-catalyzed system using phosphoramidite as ligands was applied to N-arylation of alkylamines and N(H)-heterocycles with aryl iodides and heteroaryl bromides. The reactions were carried out in relative mild conditions and good to excellent yields were obtained.
- Zhang, Zhanjin,Mao, Jincheng,Zhu, Di,Wu, Fan,Chen, Huilin,Wan, Boshun
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p. 4435 - 4443
(2007/10/03)
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- Copper-catalyzed electrophilic amination of organozinc nucleophiles: Documentation of O-benzoyl hydroxylamines as broadly useful R2N(+) and RHN(+) synthons
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This paper details new copper-catalyzed electrophilic amination reactions of diorganozinc reagents using O-benzoyl hydroxylamines as electrophilic nitrogen sources that may be accessed in one step. Simple and functionalized aryl, heteroaryl-, benzyl, n-alkyl, sec-alkyl, and tert-alkyl nucleophiles couple with R2NOC(O)Ph and RHNOC(O)Ph reagents in the presence of catalytic quantities of copper salts to provide tertiary and secondary amines, respectively, in generally good yields. In many cases, the product may be isolated analytically pure after a simple extractive workup. The amination process is shown to tolerate a significant degree of steric demand. The amination of nominally unreactive Caryl-H bonds via a sequential directed ortho metalation/transmetalation/catalytic amination reaction sequence is detailed. The direct Cu-catalyzed amination of Grignard reagents using cocatalysis by ZnCl2 is described.
- Herman, Ashley M.,Johnson, Jeffrey S.
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p. 219 - 224
(2007/10/03)
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- Highly reactive, general, and long-lived catalysts for coupling heteroaryl and aryl chlorides with primary nitrogen nucleophiles
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Resisting pathways for decomposition followed by palladium complexes of monodentate ligands is one characteristic of the highly reactive but long-lived catalyst generated from the Josiphos ligand L and palladium. It catalyzes under mild conditions the coupling of primary amines with chloropyridines and chloroarenes in high yield with low catalyst loadings (see scheme).
- Shen, Qilong,Shekhar, Shashank,Stambuli, James P.,Hartwig, John F.
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p. 1371 - 1375
(2007/10/03)
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- Mild and efficient copper-catalyzed N-arylation of alkylamines and N-H heterocycles using an oxime-phosphine oxide ligand
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A mild and efficient copper-catalyzed system for N-arylation of alkylamines and N-H heterocycles with aryl iodides using a novel, readily prepared and highly stable oxime-functionalized phosphine oxide ligand was developed. The coupling reactions could even be performed in solvent-free conditions with moderate to good yields.
- Xu, Lei,Zhu, Di,Wu, Fan,Wang, Rongliang,Wan, Boshun
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p. 6553 - 6560
(2007/10/03)
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- Mechanism of acid-catalysed decomposition of 3-alkyl-1,3-diphenyltriazenes by trichloroacetic acid in hexane
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Eight 3-alkyl-1,3-diaryltriazenes with methyl, ethyl, propyl, butyl, pentyl, isopropyl, sec-butyl and cyclohexyl substituents were synthesized and their rate constants of decomposition by trichloroacetic acid (0.01-0.25 mol dm-3) in hexane at 25°C were measured. The kinetic model and mechanism thereof were studied by modelling of the dependences of k obs on the concentration of trichloracetic acid. On the basis of this kinetic model and the interpretation of solvent effects, a reaction mechanism was suggested according to which the triazene reacts with monomer and obviously also opens the dimer of trichloroacetic acid in a single reaction step. At the same time, a non-reactive associate between the N1 nitrogen of triazene and two molecules of trichloroacetic acid is formed in the reaction mixture. The equilibrium and rate constants depend on the addition of trichloroacetic acid as the co-solvent. Copyright
- Pytela, Oldrich,Bednar, Roman,Kavalek, Jaromir
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p. 343 - 349
(2007/10/03)
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- Copper-catalyzed amination of aromatic halides with 2-N,N-dimethylaminoethanol as solvent
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A copper-catalyzed amination of aromatic halides under mild conditions using N,N-dimethylaminoethanol as solvent is described. We have studied this reaction in some detail varying the copper source, base, water content and other parameters including the scope of useful amine and aromatic halide structures. A variety of 4-halo-N,N-cycloalkylanilines and 2-N,N-cycloalkylaminothiophenes were synthesized for further elaboration into chromophores for optoelectronic applications.
- Lu, Zhikuan,Twieg, Robert J.,Huang, Songping D.
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p. 6289 - 6292
(2007/10/03)
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- A general procedure to selectively prepare N-alkylanilines by an unexpected reaction of (Z)-(tert-butylsulfanyl)(aryl)diazenes with alkyllithium reagents
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A general procedure has been set up to prepare, selectively, the N-monoalkylanilines 7, reacting (Z)-(tert-butylsulfanyl)(aryl)diazenes 3 with alkyllithium 6 (MeLi, BuLi, s-BuLi, n-C6H13Li). The reactions were carried out in anhydrous diethyl ether at 0°C or - 78°C, depending on the reagent 6, and then at room temperature. In optimal conditions the yields of the pure products 7 (uncontaminated by dialkylation products) were from good to excellent: for 38 considered examples, 34 were positive with yields varying between 61percent and 91percent (average yield 78percent). Collateral proofs were carried out to support a hypothesized reaction mechanism.
- Barbero, Margherita,Degani, Iacopo,Dughera, Stefano,Fochi, Rita
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p. 742 - 750
(2007/10/03)
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- Mechanistic studies of the palladium-catalyzed amination of aryl halides and the oxidative addition of aryl bromides to Pd(BINAP)2 and Pd(DPPF)2: An unusual case of zero-order kinetic behavior and product inhibition
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Mechanistic studies of the amination of aryl bromides catalyzed by palladium complexes containing the chelating phosphines BINAP and DPPF are reported. The coupling of primary alkyl- and arylamines, secondary cyclic alkylamines, and secondary arylalkylamines with bromoarenes in the presence of stoichiometric base and Pd(BINAP)2 (1a) as catalyst, and the reaction of aniline with 4-Br-C6H4-t-Bu in the presence of base catalyzed by Pd(DPPF)2 (2), were studied. The stoichiometric oxidative additions of PhBr to 1a and to 2 were turnover limiting, and kinetic studies were also conducted on this individual step. The stoichiometric oxidative addition of PhBr to 1a showed an inverse first-order dependence on added ligand when the PhBr concentration was low but depended solely on the rate of chelating ligand dissociation at high [PhBr]. There was no measurable solvent effect. In addition, the rates were indistinguishable in the presence and in the absence of amines and salts that are present in the catalytic amination reactions. Similar qualitative data for the oxidative addition of PhBr to 2 was obtained by 1H NMR spectroscopy. The observed rate constants for the overall amination reactions catalyzed by 1a were shown to be zero order in aryl halide, amine, base, and added ligand, while they were first order in catalyst. These data indicated that the kinetic behavior of the overall reaction was dictated solely by the rate of ligand dissociation from 1a, as observed for the oxidative addition. When secondary amines were used, deviation from this behavior was observed. This anomalous behavior resulted from decay of catalyst rather than a change in the turnover-limiting step. A catalyst decomposition pathway that involves backbone P-C bond cleavage of the chelating bisphosphine ligands was revealed by the stoichiometric oxidative addition studies. Quantitative rate data were also obtained for reaction of 4-Br-C6H4-t-Bu with aniline in the presence of base catalyzed by 2. The observed rate constants were zero order in amine and base, inverse first order in added ligand, and first order in aryl bromide. At low concentration of added ligand, the reaction appeared to be first order in amine. However, this deviation from the expected behavior was due to reversible reaction of the catalyst with product.
- Alcazar-Roman, Luis M.,Hartwig, John F.,Rheingold, Arnold L.,Liable-Sands, Louise M.,Guzei, Ilia A.
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p. 4618 - 4630
(2007/10/03)
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- Dyes
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A dye of Formula (1): STR1 wherein: D is a group of Formula (2): STR2 or a group of Formula (3): STR3 or a group of Formula (4): STR4 The variables are defined in the specification. The dyes and dye mixtures produce blue to green shades on synthetic textile materials such as polyester which have good build up and good light- and wet-fastness.
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- REDUCTIVE ACTIVATION OF ARENES. VI. REACTION OF THE PRODUCT OF THE ONE-ELECTRON REDUCTION OF NITROBENZENE BY SODIUM IN LIQUID AMMONIA WITH ISOMERIC BUTYL IODIDES
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The reaction of the product of the reduction of nitrobenzene by one equivalent of sodium in liquid ammonia with n-butyl, sec-butyl, and isobutyl iodides leads to the corresponding N,O-dialkylphenylhydroxylamines as the major products through an SN2 mechanism.The analogous reaction with tert-butyl iodide gives approximately equal amounts of products of butylation in the benzene ring, namely, 4-tert-butylnitrobenzene and 4-tert-butylaniline, and at the nitro-group, namely, N-tert-butylaniline and N-tert-butylphenylhydroxylamine.The formation of these N-tert-butyl produ cts is probably the result of the transfer of an electron from the nitrobenzene radical-anion to the alkyl iodide and subsequent recombination of the tert-butyl radical with the nitrobenzene radical-anion.The increase in the fraction of tert-butylation at the nitro group in going from hexamethylphosphorotriamide or its mixture with tetrahydrofuran as the solvent to liquid nitrogen is probably a consequence of a greater role for interaction with the medium, which affects the distribution of the spin density in the nitrobenzene radical-anion or on the relative stability of the transition states responsible for the competing recombination pathways.
- Selivanov, V. A.,Shteingarts, V. D.
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p. 1654 - 1662
(2007/10/02)
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- A simple method for preparation of secondary aromatic amines
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A simple and efficient method for the preparation of secondary N-alkylarylamines via reductive amination of ketones with primary aromatic amines using activated zinc/acetic acid is described. It requires only equimolar amounts of the starting compounds and affords good yields of the corresponding amines (50-90%). It is not applicable to aldehydes nor aliphatic amines.
- Micovic,Ivanovic,Piatak,Bojic
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p. 1043 - 1045
(2007/10/02)
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- EPR and ENDOR Study of Chiral Nitroxides
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Racemic and achiral alkyl aryl nitroxides were examined at various temperatures.The restricted rotation of the aminoxyl substituents was indicated both by the β-proton coupling constants and by the inequivalence of the aromatic ortho protons.These results
- Stegmann, Hartmut B.,Schaber, Frank-Martin,Schuler, Paul,Scheffler, Klaus
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p. 887 - 891
(2007/10/02)
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- Ruthenium-Catalyzed N-Alkylation and N-Benzylation of Aminoarenes with Alkohols
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Aminoarenes were readily converted into secondary and tertiary amines by the reaction at 150-180 deg C with primary alcohols in the presence of a catalytic amount (1 mol percent based on the aminoarene) of a ruthenium complex.Dichlorotris(triphenylphosphine)ruthenium was the most effective catalyst precursor.Secondary amines were obtained in excellent yields when aminoarenes reacted with an equimolar amount of alcohols.With excess alcohols, tertiary amines were obtained predominantly.Kinetic measurements revealed that the rate had zero-order dependence on aminoarene concentration and first-order dependence on alcohol concentration and initial concentration of the ruthenium catalyst.From the kinetic features, the possible catalytic cycle, which includes the nucleophilic attack of the aminoarene on aldehyde intermediate, was postulated.
- Watanabe, Yoshihisa,Tsuji, Yasushi,Ige, Hitoshi,Ohsugi, Yukihiro,Ohta, Tetsuo
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p. 3359 - 3363
(2007/10/02)
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- THE RUTHENIUM CATALYZED N-ALKYLATION AND N-HETEROCYCLIZATION OF ANILINE USING ALCOHOLS AND ALDEHYDES
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Aniline reacts with saturated and 2,3-unsaturated alcohols in the presence of ruthenium catalyst at 180 deg C to give N-alkylanilines and 2,3-alkylquinolines in good yields.
- Watanabe, Yoshihisa,Tsuji, Yasushi,Ohsugi, Yukihiro
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p. 2667 - 2670
(2007/10/02)
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