Efficient and Versatile Catalytic Systems for the N-Methylation of Primary Amines with Methanol Catalyzed by N-Heterocyclic Carbene Complexes of Iridium

Synthesis ◽  
2018 ◽  
Vol 50 (23) ◽  
pp. 4617-4626 ◽  
Author(s):  
Ken-ichi Fujita ◽  
Genki Toyooka ◽  
Akiko Tuji
Keyword(s):  
Low Temperatures ◽  
Aromatic Amines ◽  
Catalytic Performance ◽  
Aliphatic Amines ◽  
Primary Amines ◽  
Iridium Complexes ◽  
Reaction Conditions ◽  
Catalytic Systems ◽  
Carbene Complexes ◽  
Amine Compounds

Efficient and versatile catalytic systems were developed for the N-methylation of both aliphatic and aromatic primary amines using methanol as the methylating agent. Iridium complexes bearing an N-heterocyclic carbene (NHC) ligand exhibited high catalytic performance for this type of transformation. For aliphatic amines, selective N,N-dimethylation was achieved at low temperatures (50–90 °C). For aromatic amines, selective N-monomethylation and selective N,N-dimethylation were accomplished by simply changing the reaction conditions (presence or absence of a base with an appropriate catalyst). These findings can be used to develop methods for synthesizing useful amine compounds having N-methyl or N,N-dimethyl moieties.

Efficient Copper-Catalysed Synthesis of Carbazoles by Double N-Arylation of Primary Amines with 2,2′-Dibromobiphenyl in the Presence of Air

Synlett ◽  
2021 ◽  
Author(s):  
Tran Quang Hung ◽  
Tuan Thanh Dang ◽  
Peter Langer ◽  
Ha Nam Do ◽  
Nguyen Minh Quan ◽  
...  
Keyword(s):  
Aromatic Amines ◽  
Aliphatic Amines ◽  
Primary Amines ◽  
Coupling Reactions ◽  
Carbazole Derivatives ◽  
High Yields

AbstractAn efficient Cu-catalyzed synthesis of carbazole derivatives is reported, which proceeds by double C–N coupling reactions of 2,2′-dibromobiphenyl and amines in the presence of air. The reaction is robust, proceeds in high yields, and tolerates a series of amines including neutral, electron-rich, electron-deficient aromatic amines and aliphatic amines.

scholarly journals Efficient N-formylation of primary aromatic amines using novel solid acid magnetic nanocatalyst

RSC Advances ◽  
2020 ◽  
Vol 10 (67) ◽  
pp. 41229-41236
Author(s):  
Jitendra Kumar Yadav ◽  
Priyanka Yadav ◽  
Satish K. Awasthi ◽  
Alka Agarwal
Keyword(s):  
Magnetic Nanoparticles ◽  
Aromatic Amines ◽  
Sulfonic Acid ◽  
Solid Acid ◽  
Recyclable Catalyst ◽  
Primary Amines ◽  
Magnetic Nanocatalyst ◽  
Reaction Conditions ◽  
Primary Aromatic Amines ◽  
First Time

Sulfonic acid functionalized over biguanidine fabricated silica-coated heterogeneous magnetic nanoparticles (NP@SO3H) have been synthesized, well characterized and explored for the first time, as an efficient and recyclable catalyst for N-formylation of primary amines under mild reaction conditions.

Methyl-α-d-glucopyranoside as Green Ligand for Selective Copper-Catalyzed N-Arylation

Synthesis ◽  
2019 ◽  
Vol 51 (24) ◽  
pp. 4590-4600
Author(s):  
Yuanguang Chen ◽  
Fangyu Du ◽  
Fengyang Chen ◽  
Qifan Zhou ◽  
Guoliang Chen
Keyword(s):  
Copper Powder ◽  
Aromatic Amines ◽  
High Yield ◽  
Heterocyclic Amine ◽  
Reaction Conditions ◽  
Good Tolerance ◽  
Aryl Chlorides ◽  
Amine Compounds ◽  
Nitrogen Heterocyclic

In the selective N-arylation of amines or azoles with aryl halides­, methyl-α-d-glucopyranoside (MG) was found to function as a green ligand of copper powder. In addition, nitrogen heterocyclic amine compounds can also undergo the N-arylation coupling with heterocyclic aryl chlorides. This process allows access to a variety of aromatic amines and aryl azoles under mild reaction conditions, has good tolerance, and proceeds in moderate to high yield.

scholarly journals Asymmetric Hydrogenation of 1-aryl substituted-3,4-Dihydroisoquinolines with Iridium Catalysts Bearing Different Phosphorus-Based Ligands

Catalysts ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 914
Author(s):  
Giorgio Facchetti ◽  
Michael S. Christodoulou ◽  
Eleonora Binda ◽  
Marco Fusè ◽  
Isabella Rimoldi
Keyword(s):  
Asymmetric Hydrogenation ◽  
Catalytic Performance ◽  
Phosphine Ligand ◽  
Iridium Complexes ◽  
Complete Conversion ◽  
Catalytic Systems ◽  
Iridium Catalysts ◽  
Substituted 1

Starting from the chiral 5,6,7,8-tetrahydroquinolin-8-ol core, a series of amino-phosphorus-based ligands was realized. The so-obtained amino-phosphine ligand (L1), amino-phosphinite (L2) and amino-phosphite (L3) were evaluated in iridium complexes together with the heterobiaryl diphosphines tetraMe-BITIOP (L4), Diophep (L5) and L6 and L7 ligands, characterized by mixed chirality. Their catalytic performance in the asymmetric hydrogenation (AH) of the model substrate 6,7-dimethoxy-1-phenyl-3,4-dihydroisoquinoline 1a led us to identify Ir-L4 and Ir-L5 catalysts as the most effective. The application of these catalytic systems to a library of differently substituted 1-aryl-3,4-dihydroisoquinolines afforded the corresponding products with variable enantioselective levels. The 4-nitrophenyl derivative 3b was obtained in a complete conversion and with an excellent 94% e.e. using Ir-L4, and a good 76% e.e. was achieved in the reduction of 2-nitrophenyl derivative 6a using Ir-L5.

Ionic Liquid-assisted Preparation of Two-dimensional ZnO/Fe3O4 Nano-composites and their Application in Polysubstituted Pyrroles Synthesis

2020 ◽  
Vol 23 (1) ◽  
pp. 55-65
Author(s):  
Hossein Karami ◽  
Maryam Sabbaghan ◽  
Zinatossadat Hossaini ◽  
Faramarz Rostami-Charati
Keyword(s):  
Ionic Liquid ◽  
Catalytic Performance ◽  
Sem Analysis ◽  
Soft Template ◽  
Primary Amines ◽  
Nano Composites ◽  
Two Dimensional ◽  
Catalytic Systems ◽  
Green Catalyst ◽  
Excellent Catalytic Performance

Aim and Objective: Ionic liquids are a suitable medium for stabilization and preparation of catalytic systems. Materials and Methods: The two-dimensional (2D) ZnO/Fe3O4 nanocomposites were synthesized using ionic liquid [OMIM]Br as a stabilizer and soft template. The nanocomposites were characterized via FTIR, XRD, VSM and SEM analysis. Results: The catalytic activity of these composites was evaluated using a multicomponent reaction of primary amines, acetylacetone, and 2-bromoacetophenone. Conclusion: 2D ZnO/Fe3O4 as a recyclable and green catalyst showed excellent catalytic performance for the preparation of poly-substituted pyrroles.

scholarly journals The Catalytic Oxidation of Formaldehyde by FeOx-MnO2-CeO2 Catalyst: Effect of Iron Modification

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 555
Author(s):  
Yaxin Dong ◽  
Chenguang Su ◽  
Kai Liu ◽  
Haomeng Wang ◽  
Zheng Zheng ◽  
...  
Keyword(s):  
Low Temperatures ◽  
Oxygen Vacancies ◽  
Catalytic Performance ◽  
Active Oxygen ◽  
Molar Ratio ◽  
N2 Adsorption ◽  
Structure Activity ◽  
Iron Modification ◽  
Surface Active ◽  
Catalyst Effect

A series of FeOx-MnO2-CeO2 catalysts were synthesized by the surfactant-templated coprecipitation method and applied for HCHO removal. The influence of Fe/Mn/Ce molar ratio on the catalytic performance was investigated, and the FeOx-MnO2-CeO2 catalyst exhibited excellent catalytic activity, with complete HCHO conversion at low temperatures (40 °C) when the molar ratio of Fe/Mn/Ce was 2/5/5. The catalysts were characterized by N2 adsorption and desorption, XRD, H2-TPR, O2-TPD and XPS techniques to illustrate their structure–activity relationships. The result revealed that the introduction of FeOx into MnO2-CeO2 formed a strong interaction between FeOx-MnO2-CeO2, which facilitated the improved dispersion of MnO2-CeO2, subsequently increasing the surface area and aiding pore development. This promotion effect of Fe enhanced the reducibility and produced abundant surface-active oxygen. In addition, a great number of Oα is beneficial to the intermediate decomposition, whereas the existence of Ce3+ favors the formation of oxygen vacancies on the surface of the catalyst, all of which contributed to HCHO oxidation at low temperatures.

scholarly journals Selective Styrene Oxidation to Benzaldehyde over Recently Developed Heterogeneous Catalysts

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1680
Author(s):  
Marta A. Andrade ◽  
Luísa M. D. R. S. Martins
Keyword(s):  
Heterogeneous Catalysts ◽  
Carbon Materials ◽  
Oxygen Species ◽  
Styrene Oxidation ◽  
Reaction Conditions ◽  
Reactive Metal ◽  
Catalytic Systems ◽  
Tert Butyl Hydroperoxide ◽  
Metal Organic ◽  
Important Intermediate

The selective oxidation of styrene under heterogeneous catalyzed conditions delivers environmentally friendly paths for the production of benzaldehyde, an important intermediate for the synthesis of several products. The present review explores heterogeneous catalysts for styrene oxidation using a variety of metal catalysts over the last decade. The use of several classes of supports is discussed, including metal–organic frameworks, zeolites, carbon materials and silicas, among others. The studied catalytic systems propose as most used oxidants tert-butyl hydroperoxide, and hydrogen peroxide and mild reaction conditions. The reaction mechanism proceeds through the generation of an intermediate reactive metal–oxygen species by catalyst-oxidant interactions. Overall, most of the studies highlight the synergetic effects among the metal and support for the activity and selectivity enhancement.

Addition of Aliphatic and Aromatic Amines to Catechol in Aqueous Solution Under Oxidizing Conditions

1989 ◽  
Vol 42 (3) ◽  
pp. 365 ◽  
Author(s):  
MK Manthey ◽  
SG Pyne ◽  
RJW Truscott
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Aromatic Amines ◽  
Aliphatic Amines ◽  
Substitution Pattern ◽  
Vinylogous Amides ◽  
The Stability

The oxidation of catechol in the presence of two aliphatic and aromatic amines has been investigated. In aqueous solutions of pH 7.0 and 11.7, the substitution pattern of the adduct was dependent on the type of amine used. Aromatic amines produced 4,5-disubstituted o-quinones, whereas aliphatic amines gave either 2,4,5-trisubstituted or 2,4-disubstituted o-quinone adducts. A rationale based upon the stability of vinylogous amides is presented to account for the observed substitution pattern.

scholarly journals USE OF CERAMIC MATERIAL (CEMENT CLINKER) FOR THE PRODUCTION OF BIODIESEL

2013 ◽  
Vol 22 ◽  
pp. 71-78
Author(s):  
SUNNY SONI ◽  
MADHU AGARWAL
Keyword(s):  
Soybean Oil ◽  
Edible Oils ◽  
Methyl Esters ◽  
Catalytic Performance ◽  
Cement Clinker ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Rural Economic Development ◽  
Additional Demand ◽  
Biodiesel Fuels

Biodiesel is a renewable liquid fuel made from natural, renewable biological sources such as edible and non edible oils. Over the last years, biodiesel has gained more market due to its benefits and because it appears as the natural substitute for diesel. Reasons for growing interest in biodiesel include its potential for reducing noxious emissions, potential contributions to rural economic development, as an additional demand center for agricultural commodities, and as a way to reduce reliance on foreign oil. Biodiesel was prepared from soybean oil by transesterification with methanol in the presence of cement clinker. Cement clinker was examined as a catalyst for a conversion of soybean oil to fatty acid methyl esters (FAMEs). It can be a promising heterogeneous catalyst for the production of biodiesel fuels from soybean oil because of high activity in the conversion and no leaching in the transesterification reaction. The reaction conditions were optimized. A study for optimizing the reaction parameters such as the reaction temperature, and reaction time, was carried out. The catalyst cement clinker composition was characterized by XRF. The results demonstrate that the cement clinker shows high catalytic performance & it was found that the yield of biodiesel can reach as high as 84.52% after 1 h reaction at 65°C, with a 6:1 molar ratio of methanol to oil, 21 wt% KOH/cement clinker as catalyst.

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