- Reusable Co-nanoparticles for general and selectiveN-alkylation of amines and ammonia with alcohols
-
A general cobalt-catalyzedN-alkylation of amines with alcohols by borrowing hydrogen methodology to prepare different kinds of amines is reported. The optimal catalyst for this transformation is prepared by pyrolysis of a specific templated material, which is generatedin situby mixing cobalt salts, nitrogen ligands and colloidal silica, and subsequent removal of silica. Applying this novel Co-nanoparticle-based material, >100 primary, secondary, and tertiary amines includingN-methylamines and selected drug molecules were conveniently prepared starting from inexpensive and easily accessible alcohols and amines or ammonia.
- Beller, Matthias,Gawande, Manoj B.,Jagadeesh, Rajenahally V.,Kadam, Ravishankar G.,Li, Xinmin,Ma, Zhuang,Petr, Martin,Zbo?il, Radek,Zhou, Bei
-
p. 111 - 117
(2022/01/06)
-
- Trimethyl Borate-Catalyzed, Solvent-Free Reductive Amination
-
Solvent-free reductive amination of aldehydes and ketones with aliphatic and aromatic amines in high-to-excellent yields has been achieved with sub-stoichiometric trimethyl borate as promoter and ammonia borane as reductant.
- Ramachandran, P. Veeraraghavan,Choudhary, Shivani,Singh, Aman
-
p. 4274 - 4280
(2021/03/09)
-
- Carbon monoxide-driven osmium catalyzed reductive amination harvesting WGSR power
-
Herein, we present the first example of Os-catalyzed efficient reductive amination under water-gas shift reaction conditions. The developed catalytic systems are formedin situin aqueous solutions, employ as small as 0.0625 mol% osmium and are capable of delivering reductive amination products for a broad range of aliphatic and aromatic carbonyl compounds and amines. The scope of the reaction, active catalytic systems, possible limitations of the method and DFT-supported mechanistic considerations are discussed in detail in the manuscript.
- Afanasyev, Oleg I.,Biriukov, Klim O.,Chusov, Denis,Godovikova, Maria,Loginov, Dmitry A.,Nelyubina, Yulia V.,Tsygankov, Alexey A.,Vasilyev, Dmitry V.,Vinogradov, Mikhail M.
-
p. 4922 - 4930
(2021/07/26)
-
- Design, Synthesis, and Structure-Activity Relationship of Economical Triazole Sulfonamide Aryl Derivatives with High Fungicidal Activity
-
Plant fungal diseases have caused great decreases in crop quality and yield. As one of the considerable agricultural diseases, cucumber downy mildew (CDM) caused by pseudoperonospora cubensis seriously influences the production of cucumber. Amisulbrom is a commercial agricultural fungicide developed by Nissan Chemical, Ltd., for the control of oomycetes diseases that is highly effective against CDM. However, the synthesis of amisulbrom has a high cost because of the introduction of the bromoindole ring. In addition, the continuous use of amisulbrom might increase the risk of resistance development. Hence, there is an imperative to develop active fungicides with new scaffolds but low cost against CDM. In this study, a series of 1,2,4-triazole-1,3-disulfonamide derivatives were designed, synthesized, and screened. Compound 1j showed a comparable fungicidal activity with amisulbrom, but it was low cost and ecofriendly. It has the potential to be developed as a new fungicide candidate against CDM. Further investigations of structure-activity relationship exhibited the structural requirements of 1,2,4-triazole-1,3-disulfonamide and appropriate modification in N-alkyl benzylamine groups with high fungicidal activity. This research will provide powerful guidance for the design of highly active lead compounds with a novel skeleton and low cost.
- Hao, Ge-Fei,Li, Yi-Tao,Lin, Jian,Xu, Jun-Xing,Yao, Wen-Qiang,Zhou, Si
-
p. 6792 - 6801
(2020/07/08)
-
- One-pot, chemoselective synthesis of secondary amines from aryl nitriles using a PdPt-Fe3O4nanoparticle catalyst
-
We have developed a new catalytic method for the one-pot, cascade synthesis of unsymmetrical secondary amines via the reductive amination of aryl nitriles with nitroalkanes using a PdPt-Fe3O4 nanoparticle (NP) catalyst. The use of a bimetallic catalyst resulted in enhanced reactivity and selectivity compared to that of either monometallic Pd-Fe3O4 or the Pt-Fe3O4 NP catalyst. Using this bimetallic catalytic system, we were successful in the synthesis of various unsymmetrical secondary amines under mild conditions. However, aryl nitriles containing an electron-donating substituent were rather resistant to the reductive amination, and when hexafluoroisopropanol (HFIP) was used as a co-solvent, the reaction selectivity and yield for unsymmetrical secondary amines increased dramatically. Using the catalyst system, one-pot, gram-scale synthesis of indole was possible from 2-nitrophenylacetonitrile. Due to the magnetic property of the Fe3O4 support, the bimetallic catalyst could easily be recycled using an external magnet at least four times.
- Byun, Sangmoon,Cho, Ahra,Cho, Jin Hee,Kim, B. Moon
-
p. 4201 - 4209
(2020/09/23)
-
- Cine-Silylative Ring-Opening of α-Methyl Azacycles Enabled by the Silylium-Induced C-N Bond Cleavage
-
Described herein is the development of a borane-catalyzed cine-silylative ring-opening of α-methyl azacycles. This transformation involves four-step cascade processes: (i) exo-dehydrogenation of alicyclic amine, (ii) hydrosilylation of the resultant enamine, (iii) silylium-induced cis-β-amino elimination to open the ring skeleton, and (iv) hydrosilylation of the terminal olefin. The present borane catalysis also works efficiently for the C-N bond cleavage of acyclic tertiary amines. On the basis of experimental and computational studies, the silicon atom was elucidated to play a pivotal role in the β-amino elimination step.
- Zhang, Jianbo,Chang, Sukbok
-
p. 12585 - 12590
(2020/08/21)
-
- High-Throughput Screening of Reductive Amination Reactions Using Desorption Electrospray Ionization Mass Spectrometry
-
This study describes the latest generation of a high-throughput screening system that is capable of screening thousands of organic reactions in a single day. This system combines a liquid handling robot with desorption electrospray ionization (DESI) mass spectrometry (MS) for a rapid reaction mixture preparation, accelerated synthesis, and automated MS analysis. A total of 3840 unique reductive amination reactions were screened to demonstrate the throughputs that are capable with the system. Products, byproducts, and intermediates were all monitored in full-scan mass spectra, generating a complete view of the reaction progress. Tandem mass spectrometry experiments were conducted to verify the identity of the products formed. The amine and electrophile reactivity trends represented in the data match what is expected from theory, indicating that the system accurately models the reaction performance. The DESI results correlated well with those generated using more traditional mass spectrometry techniques like liquid chromatography-mass spectrometry, validating the data generated by the system.
- Cooks, R. Graham,Ferreira, Christina R.,Li, Yangjie,Logsdon, David L.,Paschoal Sobreira, Tiago Jose,Thompson, David H.
-
supporting information
p. 1647 - 1657
(2020/10/26)
-
- Catalyst-Free Reductive Coupling of Aromatic and Aliphatic Nitro Compounds with Organohalides
-
A rare reductive coupling of nitro compounds with organohalides has been realized. The reaction is initiated by a partial reduction of the nitro group to a nitrenoid intermediate. Therefore, not only aromatic but also aliphatic nitro compounds are efficiently transformed into monoalkylated amines, with organohalides as the alkylating agent. Given the innate reactivity of the nitrenoid, a catalyst is not required, resulting in a high tolerance for aryl halide substituents in both starting materials.
- Rauser, Marian,Eckert, Raphael,Gerbershagen, Max,Niggemann, Meike
-
p. 6713 - 6717
(2019/04/14)
-
- Unlocking the catalytic potential of tris(3,4,5-trifluorophenyl)borane with microwave irradiation
-
The catalytic activity of tris(3,4,5-trifluorophenyl)borane has been explored in the 1,2-hydroboration reactions of unsaturated substrates. Under conventional conditions, the borane was found to be active only in the hydroboration of aldehyde, ketone and imine substrates, with alkenes and alkynes not being reduced effectively. The use of microwave irradiation on the other hand has permitted alkenes and alkynes to be hydroborated in good yields.
- Carden, Jamie L.,Gierlichs, Lukas J.,Wass, Duncan F.,Browne, Duncan L.,Melen, Rebecca L.
-
p. 318 - 321
(2019/01/09)
-
- Metal- and Base-Free Room-Temperature Amination of Organoboronic Acids with N-Alkyl Hydroxylamines
-
We have found that readily available N-alkyl hydroxylamines are effective reagents for the amination of organoboronic acids in the presence of trichloroacetonitrile. This amination reaction proceeds rapidly at room temperature and in the absence of added metal or base, it tolerates a remarkable range of functional groups, and it can be used in the late-stage assembly of two complex units.
- Sun, Hong-Bao,Gong, Liang,Tian, Yu-Biao,Wu, Jin-Gui,Zhang, Xia,Liu, Jie,Fu, Zhengyan,Niu, Dawen
-
supporting information
p. 9456 - 9460
(2018/07/29)
-
- Direct Reductive N-Functionalization of Aliphatic Nitro Compounds
-
The first general protocol for the direct reductive N-functionalization of aliphatic nitro compounds is presented. The nitro group is partially reduced to a nitrenoid, with a mild and readily available combination of B2pin2 and zinc organyls. Thereby, the formation of an unstable nitroso intermediate is avoided, which has so far severely limited reductive transformations of aliphatic nitro compounds. The reaction is concluded by an electrophilic amination of zinc organyls.
- Rauser, Marian,Ascheberg, Christoph,Niggemann, Meike
-
p. 3970 - 3974
(2018/02/26)
-
- Inhibition of the Cysteine Protease Human Cathepsin L by Triazine Nitriles: Amide???Heteroarene π-Stacking Interactions and Chalcogen Bonding in the S3 Pocket
-
We report an extensive “heteroarene scan” of triazine nitrile ligands of the cysteine protease human cathepsin L (hCatL) to investigate π-stacking on the peptide amide bond Gly67–Gly68 at the entrance of the S3 pocket. This heteroarene???peptide bond stacking was supported by a co-crystal structure of an imidazopyridine ligand with hCatL. Inhibitory constants (Ki) are strongly influenced by the diverse nature of the heterocycles and specific interactions with the local environment of the S3 pocket. Binding affinities vary by three orders of magnitude. All heteroaromatic ligands feature enhanced binding by comparison with hydrocarbon analogues. Predicted energetic contributions from the orientation of the local dipole moments of heteroarene and peptide bond could not be confirmed. Binding of benzothienyl (Ki=4 nm) and benzothiazolyl (Ki=17 nm) ligands was enhanced by intermolecular C?S???O=C interactions (chalcogen bonding) with the backbone C=O of Asn66 in the S3 pocket. The ligands were also tested for the related enzyme rhodesain.
- Giroud, Maude,Ivkovic, Jakov,Martignoni, Mara,Fleuti, Marianne,Trapp, Nils,Haap, Wolfgang,Kuglstatter, Andreas,Benz, J?rg,Kuhn, Bernd,Schirmeister, Tanja,Diederich, Fran?ois
-
supporting information
p. 257 - 270
(2017/02/15)
-
- Simple Metal-Free Direct Reductive Amination Using Hydrosilatrane to Form Secondary and Tertiary Amines
-
This work describes the use of cheap, safe, and easy-to-handle hydrosilatrane as the reductant in direct reductive amination reactions. This efficient method enables a facile, metal-free access to secondary and tertiary amines from a wide range of aldehydes and ketones, with the synthesis of tertiary amines requiring no additives at all. This reaction demonstrates excellent functional group tolerance, chemoselectivity, and scalability. (Figure presented.).
- Varjosaari, Sami E.,Skrypai, Vladislav,Suating, Paolo,Hurley, Joseph J. M.,Lio, Ashley M. De,Gilbert, Thomas M.,Adler, Marc J.
-
supporting information
p. 1872 - 1878
(2017/06/09)
-
- Synthesis and algicidal activity of new dichlorobenzylamine derivatives against harmful red tides
-
In the present study, we synthesized 65 dichlorobenzylamine derivatives and investigated their algicidal activity against harmful red tides. The 3,4-dichlorobenzylamine derivatives showed relatively high activity against Cochlodinium polykrikoides, Heterosigma akashiwo, Chattonella marina, and Heterocapsa circularisquama, and the synthesized compounds 27, 28, 33, 34, 35, and 36 showed the highest algicidal activity after 24 h at 0.1 ~ 1.0 μM LC50 against the four harmful algae species. To verify the safety of the compounds, acute ecotoxicology tests using the water flea (Daphnia magna) and zebrafish (Danio rerio) were conducted, and the tests confirmed that compounds 33 and 34 were not harmful because the target organisms showed high survival rates at 15 μM. The results indicate that compounds 33 and 34 are suitable substances for use in controlling harmful algae species.
- Choi, Dubok,Yu, Sunjong,Baek, Seung Ho,Kang, Yoon-Ho,Chang, Young-Cheol,Cho, Hoon
-
p. 463 - 476
(2016/07/30)
-
- Fluorine Scan of Inhibitors of the Cysteine Protease Human Cathepsin L: Dipolar and Quadrupolar Effects in the π-Stacking of Fluorinated Phenyl Rings on Peptide Amide Bonds
-
The π-stacking of fluorinated benzene rings on protein backbone amide groups was investigated, using a dual approach comprising enzyme-ligand binding studies complemented by high-level quantum chemical calculations. In the experimental study, the phenyl substituent of triazine nitrile inhibitors of human cathepsin L (hCatL), which stacks onto the peptide amide bond Gly67-Gly68 at the entrance of the S3 pocket, was systematically fluorinated, and differences in inhibitory potency were measured in a fluorimetric assay. Binding affinity is influenced by lipophilicity (clog P), the dipole and quadrupole moments of the fluorinated rings, but also by additional interactions of the introduced fluorine atoms with the local environment of the pocket. Generally, the higher the degree of fluorination, the better the binding affinities. Gas phase calculations strongly support the contributions of the molecular quadrupole moments of the fluorinated phenyl rings to the π-stacking interaction with the peptide bond. These findings provide useful guidelines for enhancing π-stacking on protein amide fragments. The introduction of fluorine substituents on benzene rings of triazine nitrile inhibitors for human cathepsin L (hCatL) enhances the π-stacking of these rings with peptide amide bonds at the entrance of the S3 pocket. The degree and pattern of fluorine substitution matter, which is explained in an experimental/computational study by changes in lipophilicity, dipolar and quadrupolar interactions, and additional protein-ligand interactions beyond the arene-amide stacking.
- Giroud, Maude,Harder, Michael,Kuhn, Bernd,Haap, Wolfgang,Trapp, Nils,Schweizer, W. Bernd,Schirmeister, Tanja,Diederich, Fran?ois
-
supporting information
p. 1042 - 1047
(2016/06/01)
-
- Transformation of N,N-diisopropylarylmethylamines into N-isopropylarylmethylamines with molecular iodine
-
N,N-Diisopropylarylmethylamines were smoothly converted into the corresponding N-isopropylarylmethylamines by the reaction with molecular iodine in the presence of Na2CO3 in chloroform at 60 °C. Other related tertiary amines were also transformed into the corresponding secondary amines by the reaction with molecular iodine under the same reaction conditions.
- Ezawa, Masatoshi,Moriyama, Katsuhiko,Togo, Hideo
-
p. 6689 - 6692
(2016/02/03)
-
- General and selective reductive amination of carbonyl compounds using a core-shell structured Co3O4/NGr@C catalyst
-
The application of heterogenized non-noble metal-based catalysts in selective catalytic hydrogenation processes is still challenging. In this respect, the preparation of a well-defined cobalt-based catalyst was investigated by immobilization of the corresponding cobalt(ii)-phenanthroline-chelate on Vulcan XC72R carbon powder. The formed core-shell structured cobalt/cobalt oxide nanocomposites are encapsulated by nitrogen-enriched graphene layers. This promising cheap heterogeneous catalyst allows for an efficient domino reductive amination of carbonyl compounds with nitroarenes. This journal is
- Stemmler, Tobias,Westerhaus, Felix A.,Surkus, Annette-Enrica,Pohl, Marga-Martina,Junge, Kathrin,Beller, Matthias
-
p. 4535 - 4540
(2014/12/10)
-
- Iron-catalyzed synthesis of secondary amines: On the way to green reductive aminations
-
Amines represent important intermediates in chemical and biological processes. Herein, we describe the use of a nanostructured iron-based catalyst for the tandem reductive amination between nitroarenes and aldehydes using hydrogen as reductant. The nanostructured iron-catalyst is prepared by immobilization of an iron-phenanthroline complex onto a commercially available carbon support. In the reaction sequence a primary amine is formed in situ from the corresponding nitro compound. Reversible condensation with aldehydes forms the respective imines, which are finally reduced to the desired secondary amine. This synthesis of secondary amines is atom-economical and environmentally attractive using cheap and readily available organic compounds as starting materials.
- Stemmler, Tobias,Surkus, Annette-Enrika,Pohl, Marga-Martina,Junge, Kathrin,Beller, Matthias
-
p. 3012 - 3016
(2015/09/28)
-
- Tandem synthesis of amides and secondary amines from esters with primary amines under solvent-free conditions
-
An iridium(III)-catalyzed tandem synthesis of amides and amines from esters under solvent-free conditions is described. A commercially available iridium(III) complex, [Cp*IrCl2]2, with sodium acetate showed the best activity for the synthesis of amides and secondary amines. The amide was formed by ester-amide exchange which generates an alcohol in situ which is subsequently transformed to a secondary amine via hydrogen autotransfer. This synthetic protocol with high atom economy generates water as the sole by-product and can afford amides and amines from various esters in a one-pot reaction, expanding the synthetic versatility of ester transformations.
- Lee, Jeongbin,Muthaiah, Senthilkumar,Hong, Soon Hyeok
-
p. 2653 - 2660
(2014/09/17)
-
- Coupling of two multistep catalytic cycles for the one-pot synthesis of propargylamines from alcohols and primary amines on a nanoparticulated gold catalyst
-
A one-pot reaction was performed with a nanoparticulated gold catalyst. A secondary amine is formed through N-monoalkylation of a primary amine with an alcohol by a borrowing hydrogen methodology in a three-step reaction. The secondary amine formed enters into a second A3-coupling cycle to give propargylamines. The multistep reaction requires a gold species formed and stabilized on a ceria surface. Copyright
- Corma, Avelino,Navas, Javier,Sabater, Maria J.
-
p. 14150 - 14156
(2013/01/15)
-
- Microwave-assisted solventless reaction of iridium-catalyzed alkylation of amines with alcohols in the absence of base
-
Microwave-assisted iridium catalyzed alkylation of amines with alcohols was undertaken under solvent-free and base-free conditions. Such alkylation reactions are green, atom-economic, and effective for mono-, di-, and triaklyation of amines. Good isolated yields were obtained for mono- and dialkylated amines using stoichiometric amounts of amines and alcohols, in the presence of 1 mol % [Cp*IrCl2]2. Reasonable yields of trialkylated products were obtained using 4 equiv of alcohols.
- Zhang, Weixing,Dong, Xiaochun,Zhao, Weili
-
supporting information; experimental part
p. 5386 - 5389
(2011/11/29)
-
- Zinc-promoted, iridium catalyzed reductive alkylation of primary amines with aliphatic ketones in aqueous medium
-
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.
-
scheme or table
p. 689 - 691
(2010/04/02)
-
- Secondary amine formation from reductive amination of carbonyl compounds promoted by lewis acid using the InCl3ZEt3SiH system
-
A robust and reliable method has been developed for reductive amination of primary amines with various aldehydes and ketones using Zn(ClO4) 2.6H20 as a catalyst. [In-H] generated in situ via a combination of InCl3 and Et3SiH is employed as an effective reducing system. A variety of secondary amines can be synthesized in a one-pot procedure in excellent yields.
- Lee, On-Yi,Law, Ka-Lun,Yang, Dan
-
supporting information; experimental part
p. 3302 - 3305
(2009/11/30)
-
- Reductive amination agents: comparison of Na(CN)BH3 and Si-CBH
-
Reductive amination is a chemical reaction commonly employed by organic chemists in academics and the pharmaceutical industry. In this reaction a carbonyl group is converted to an amine via an imine intermediate, the formation of which is rate limiting. A major reagent necessary for the completion of this reaction is a hydride source, commonly sodium cyanoborohydride (Na(CN)BH3). The objective of this research was to compare the efficacy of Na(CN)BH3 with silica-bound cyanoborohydride (Si-CBH) as hydride sources in reductive amination reactions. Work has shown that reactions employing Si-CBH as a hydride source showed significant improvement, exhibiting an average percent conversion 25% greater than reactions using Na(CN)BH3.
- Grenga, Paolo N.,Sumbler, Brittany L.,Beland, Fran?ois,Priefer, Ronny
-
scheme or table
p. 6658 - 6660
(2010/03/03)
-
- Hydroamination of carbonyl compounds with oximes
-
N-alkyl(cycloalkyl)benzylamines, p-fluorobenzylamines, (1-phenylethyl) amines, [1-(p-fluorophenyl)ethyl]amines were synthesized by hydroamination of aldehydes and ketones with oximes.
- Tarasevich,Kozlov
-
p. 379 - 383
(2007/10/03)
-
- N-alkylation of amines under microwave irradiation: Modified eschweiler-clarke reaction
-
The N-alkylation of hexahydroazepine and benzylamine is performed under microwave irradiation in the presence of formic acid and different aldehydes or ketones. Good yields were obtained with reactive carbonyl compounds.
- Torchy,Barbry
-
p. 292 - 293
(2007/10/03)
-
- Radical cyclisations of imines and hydrazones
-
Radical cyclisation of sp3 carbon-centred radicals onto imines and hydrazones provides a new method for the synthesis of 5- and 6-membered ring nitrogen heterocycles. Cyclisation onto the electrophilic carbon of the C=N group and 5-exo stereoelectronic selectivity are the dominating mechanistic parameters. The C-centred radical intermediates were generated from benzeneselenyl precursors using Bu3SnH.
- Bowman, W. Russell,Stephenson, Peter T.,Terrett, Nicholas K.,Young, Adrian R.
-
p. 7959 - 7980
(2007/10/02)
-
- A NEW SYNTHESIS OF NITROGEN-CONTAINING HETEROCYCLES BY MEANS OF ORGANOALUMINUM REAGENTS
-
Nitrogen-containing heterocycles can be derived in synthetically good yields from a variety of carbocyclic frameworks via the successive rearrangement-alkylation sequence of hydroxylamine carbonates with trialkylaluminums.
- Fujiwara, Junya,Sano, Hiromi,,Maruoka, Keiji,Yamamoto, Hisashi
-
p. 2367 - 2370
(2007/10/02)
-