Synthesis of Amines by Reductive Amination of Aldehydes and Ketones using Co<sub>3</sub>O<sub>4</sub>/NGr@C Catalyst

Pisiewicz, Sabine; Stemmler, Tobias; Surkus, Annette‐Enrica; Junge, Kathrin; Beller, Matthias

doi:10.1002/cctc.201402527

Cited by 64 publications

(37 citation statements)

References 28 publications

(3 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Ty pically,t his one-pot reaction proceeds via imines,e namines,o ri minium cations as intermediates,which are subsequently reduced (Scheme 11 a). Co- [77] and Ni-based [78] NPs that were encapsulated by individually N-enriched graphene-type layers catalyzed the selective reductive amination of aldehydes and ketones under additivefree conditions.I nt he presence of Co- [79] and Fe-based [80] catalysts,agreen domino hydrogenation/reductive amination between nitroarenes and aldehydes also took place.R eversible condensation between the in situ formed amines and aldehydes gave the respective imines,w hich were then reduced to the desired secondary amines (Scheme 11 b).…”

Section: Reductive Aminationsmentioning

confidence: 99%

Synthesis, Characterization, and Application of Metal Nanoparticles Supported on Nitrogen‐Doped Carbon: Catalysis beyond Electrochemistry

et al. 2016

Self Cite

View full text Add to dashboard Cite

Metal nanoparticles deposited on N-doped carbon materials have emerged as novel catalysts for various organic transformations. In this Minireview, strategies for the synthesis of metal composites on N-doped carbon supports and their state-of-the-art characterization are briefly described. The catalytic application of these fascinating materials in several industrially relevant reactions, including oxidations, hydrogenations, Fischer-Tropsch syntheses, and H2 generation, is also summarized. Furthermore, the effects of nitrogen incorporation on the different catalytic systems are highlighted.

show abstract

Section: Reductive Aminationsmentioning

confidence: 99%

Synthesis, Characterization, and Application of Metal Nanoparticles Supported on Nitrogen‐Doped Carbon: Catalysis beyond Electrochemistry

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…were used. 18 Supported noble metal catalysts are considered as an excellent choice to obtain primary amines with high purity under mild reaction conditions. In this context, molecular hydrogen is considered as the most atom-economical and environmentally friendly reducing agent for reductive amination, particularly in the large-scale production.…”

Section: Introductionmentioning

confidence: 99%

Reductive amination of furfural to furfurylamine using aqueous ammonia solution and molecular hydrogen: an environmentally friendly approach

2016

View full text Add to dashboard Cite

A simple and highly efficient method was developed for the transformation of furfural (a biomass derived aldehyde) to furfurylamine by reductive amination using an aqueous solution of ammonia and molecular hydrogen as an amine source and a reducing agent, respectively. By choosing a suitable catalyst, such as Rh/Al 2 O 3 , and reaction conditions, a very high selectivity of furfurylamine (∼92%) can be achieved within the reaction time of 2 h at 80°C. A detailed analysis of the reaction system sheds some light on the reaction pathway and provides an understanding about each elementary step. The reaction was believed to proceed via an imine pathway although no such intermediate was detected because of the highly reactive nature. Optimization of different reaction parameters such as hydrogen pressure, temperature and substrate/ammonia mole ratio is shown to be critical to achieve high selectivity of furfurylamine. Timedependent reaction profiles suggested that a Schiff base type intermediate was in the detectable range, which offers indirect evidence of the formation of imine. Competitive hydrogenation and amination of an aldehyde group were strongly dictated by the nature of the metal used. The studied protocol represents an environmentally benign process for amine synthesis, which can be effectively extended to the other aldehydes also. The studied catalyst could be recycled successfully without any significant loss of catalytic activity. † Electronic supplementary information (ESI) available. See Reaction conditions: catalyst = 0.002 g, substrate = 0.2 g, substrate/ammonia (mole ratio) = 0.03, temperature = 80°C, reaction time = 2 h, P H 2 = 2 MPa. a Reaction time = 4 h. b Reaction time = 5 h. Green Chemistry PaperThis journal is

show abstract

“…Hence, merging rationally-designed suitable modified supports with cheap transition metals permits access to the design of active, selective and cheap catalytic materials thus allowing to match or to outperform noble-metal-based catalysts. During the last three years, some of us reported the preparation of active and selective NGr-decorated Co-based catalysts from the pyrolysis of in situ generated 1,10-phenanthroline (Phen) metal complexes using Vulcan® XC 72 R carbon [52][53][54][55][56][57][58][59][60], ceria [61] or α-alumina as supports [62]. Some of the obtained nanoscale catalysts exhibit a core-shell architecture in which a Co metallic core is enveloped by an oxidic sheath composed of Co3O4.…”

Section: Introductionmentioning

confidence: 99%

Co-based heterogeneous catalysts from well-defined α-diimine complexes: Discussing the role of nitrogen

Formenti

Ferretti

Topf

et al. 2017

Journal of Catalysis

Self Cite

View full text Add to dashboard Cite

‡ These authors contributed equally to this work.Abstract: Ar-BIANs and related α-diimine Co complexes were wet impregnated onto Vulcan® XC 72 R carbon black powder and used as precursors for the synthesis of heterogeneous supported nanoscale catalysts by pyrolysis under argon at 800 °C. The catalytic materials feature a core-shell structure composed of metallic Co and Co oxides decorated with nitrogen-doped graphitic layers (NGr). These catalysts display high activity in the liquid phase hydrogenation of aromatic nitro compounds (110 °C, 50 bar H2) to give chemoselectively substituted aryl amines. The catalytic activity is closely related to the amount and type of nitrogen atoms in the final catalytic material, which suggests a heterolytic activation of dihydrogen.Keywords: cobalt, hydrogenation, nitro compounds, kinetic, heterolytic activation IntroductionCatalysis is a key-technology for the manufacturing of all kinds of bulk and fine chemical products. It allows for producing chemicals avoiding the formation of undesired and useless stoichiometric side products which leads to additional cost and energy consumption [1][2][3]. Many of the industrially relevant catalytic processes in the fine chemical industry are still based on expensive and rare late transition metals such as Pd, Pt, Rh, Ru and Ir [4,[1][2][3][4][5]. Although these metals exhibit very good catalytic performance for advanced organic substrates, the decreasing availability of these elements requires the development of efficient alternative metal-based catalysts [6]. In this regard, the design of catalytic systems based on abundant and biocompatible metals is an important goal for the implementation and progress of green and sustainable chemistry. Hence, transition metals such as Fe, Co and Cu are ideal candidates, which meet these requirements [7][8][9][10]. As a matter of fact, these elements are among the most abundant metals in the Earth's upper crust, thus being readily accessible [11]. Recently, heteroatom-doped carbon materials attracted major interest in the field of metal supported heterogeneous catalysts for both chemical synthesis [12][13][14] and/or energy-relevant transformations [15,16]. Indeed, doping graphene with heteroatoms such as N, B, P, or S leads to a radical modification of the electronic properties of both the support and the supported metal [17][18][19]. Consequently, it is possible to modify the activity and adjust the selectivity of the final catalytic material towards the desired transformation. Among the various dopants, nitrogen attracted most interest [15,[20][21][22]. and applications of transition metal/N-doped graphene (NGr) based catalytic systems ranges from oxygen reduction reactions (ORR) [23][24][25][26], hydrogen evolving reactions (HER) [27,28], photocatalysis [29,30], oxidation [31][32][33][34][35][36][37][38], and reduction [39][40][41][42][43][44] reactions of organic

show abstract

Synthesis of Amines by Reductive Amination of Aldehydes and Ketones using Co₃O₄/NGr@C Catalyst

Cited by 64 publications

References 28 publications

Synthesis, Characterization, and Application of Metal Nanoparticles Supported on Nitrogen‐Doped Carbon: Catalysis beyond Electrochemistry

Synthesis, Characterization, and Application of Metal Nanoparticles Supported on Nitrogen‐Doped Carbon: Catalysis beyond Electrochemistry

Reductive amination of furfural to furfurylamine using aqueous ammonia solution and molecular hydrogen: an environmentally friendly approach

Co-based heterogeneous catalysts from well-defined α-diimine complexes: Discussing the role of nitrogen

Contact Info

Product

Resources

About

Synthesis of Amines by Reductive Amination of Aldehydes and Ketones using Co3O4/NGr@C Catalyst

Cited by 64 publications

References 28 publications

Synthesis, Characterization, and Application of Metal Nanoparticles Supported on Nitrogen‐Doped Carbon: Catalysis beyond Electrochemistry

Synthesis, Characterization, and Application of Metal Nanoparticles Supported on Nitrogen‐Doped Carbon: Catalysis beyond Electrochemistry

Reductive amination of furfural to furfurylamine using aqueous ammonia solution and molecular hydrogen: an environmentally friendly approach

Co-based heterogeneous catalysts from well-defined α-diimine complexes: Discussing the role of nitrogen

Contact Info

Product

Resources

About

Synthesis of Amines by Reductive Amination of Aldehydes and Ketones using Co₃O₄/NGr@C Catalyst