Reaction Of Aniline Research Articles

Conversion of Primary Amines to Symmetrical Secondary and Tertiary Amines using a Co‐Rh Heterobimetallic Nanocatalyst

AbstractSymmetrical tertiary amines have been efficiently realized from amine and secondary amines via deaminated homocoupling with heterogeneous bimetallic Co2Rh2/C as catalyst (molar ratio Co:Rh=2:2). Unsymmetric secondary anilines were produced from the reaction of anilines with symmetric tertiary amines. The Co2Rh2/C catalyst exhibited very high catalytic activity towards a wide range of amines and could be conveniently recycled ten times without considerable leaching.magnified image

Pd-Catalyzed Three-Component Reaction of Anilines, Ethyl Vinyl Ether, and Nitro-Paraffin: Assembly of β-Nitroamines.

A novel palladium-catalyzed amination and nitration of ethyl vinyl ether for the construction of β-nitroamine derivatives under mild conditions has been developed. This transformation provides a new strategy for the installation of amino and nitro from aromatic amines and nitro-paraffin into alkenes. Morpholine resulted in the aza-Henry reaction, while DABCO led to the unexpected rearrangement.

C-H bond sulfonylation of anilines with the insertion of sulfur dioxide under metal-free conditions.

C-H bond sulfonylation of anilines with the insertion of sulfur dioxide under metal-free conditions is described. 2-Sulfonylanilines are generated in moderate to good yields through a three-component reaction of anilines, DABCO·(SO2)2, and aryldiazonium tetrafluoroborates under mild conditions. No metal catalysts or additives are needed for this transformation. This direct C-H functionalization is highly efficient, and broad functional group tolerance is observed. A radical process is believed to be involved. In the reaction process, the arylsulfonyl radical and the tertiary amine radical cation generated in situ from DABCO·(SO2)2, and aryldiazonium tetrafluoroborate are the key intermediates. Additionally, the tertiary amine radical cation acts as the electron carrier through a single electron transfer process.

Study of Horseradish Peroxidase Fixed on Mesoporous Materials as a Chemical Reaction Catalyst

Nanostructured mesoporous materials is a new type of porous materials, which has been widely used. It has excellent capability in enzymes immobilization, but modification on the chemical bonds of the enzyme reduce the enzymatic activity and rarely used in chemical reactions. The horseradish peroxidase was immobilized on the mesoporous materials with appropriate aperture and its activity and stability was evaluated when catalyzing the nitration reaction of amines and oxidation reaction of thiourea. The optimum mesoporous material to fix the horseradish peroxidase can be obtained by mixing polyoxyethylene - polyoxypropylene-pol, yoxyethylene(P123), 1,3,5-trimethylbenzene(TMB), and tetramethoxysilane (TMOS) at a ratio of 10:1:1, whose surface area and pore volume and pore diameter calculated by BET and BJH model were 402.903m2/g, 1.084cm2/g, 1.084cm2/g respectively. The horseradish peroxidase, immobilized on the mesoporous materials, was applied for catalyzing the nitration reaction of anilines and oxidation reaction of thiourea, produced a high product yield and can be recycled. Thus, it is a strong candidate as a catalysts for oxidation reactions, to be produced at industral scale, due to its high efficiency and low cost.

Highly Efficient Rh(I) Homo- and Heterogeneous Catalysts for C-N Couplings via Hydrogen Borrowing.

Rhodium(I) complexes were explored as catalysts for the hydrogen borrowing reactions of amines and alcohols. Bidentate carbene-triazole ligands were readily synthesized via "click" reactions which allowed a diversity of ligand backbones to be accessed. The catalytic transformations are highly efficient, able to reach completion in under 6 h, and promote C-N bond formation across a range of primary alcohol and amine substrates. Moreover, site-selective catalysis can be achieved using substrates with more than one reactive site. A rhodium(I) complex covalently attached to a carbon black surface was also deployed in the hydrogen borrowing coupling reaction of aniline with benzyl alcohol. This represents the first report of a heterogeneous rhodium catalyst used for hydrogen borrowing.

Aluminosilicates with different pores structure in the synthesis of 2,2,4-trimethyl-1,2-dihydroquinoline and N-phenyl-2-propanimine

Physicochemical characteristics of microporous zeolites of various structural type (FAU, BEA, MTW), micro-meso-macroporous zeolite (H-Ymmm), and mesoporous aluminosilicate (ASM) were studied. Their catalytic activity in the reaction of aniline with acetone was examined. It was found that 2,2,4-trimethyl-1,2-dihydroquinoline was the main reaction product on the catalysts H-Ymmm and ASM (selectivity up to 68% at 100% conversion of aniline), while the reaction on zeolites with microporous structure mainly gave N-phenyl-2-propanimine (selectivity up to 91%).

Microwave-Assisted Regioselective Synthesis of 3-Functionalized Indole Derivatives via Three-Component Domino Reaction.

A microwave-assisted regioselective synthesis of 3-functionalized indole derivatives via a three-component domino reaction of anilines, arylglyoxal monohydrates, and cyclic 1,3-dicarbonyl compounds is described. The main advantages of this protocol are short reaction times, practical simplicity, its metal-free nature, the availability of starting materials, green solvents, and high regioselectivity.

FeCl3‐Mediated One‐Pot Cyclization–Aromatization of Anilines, Benzaldehydes, and Phenylacetylenes under Ball Milling: A New Alternative for the Synthesis of 2,4‐Diphenylquinolines

A straightforward and efficient method has been developed for the solvent‐free synthesis of 2,4‐diphenylquinolines via a one‐pot reaction of anilines, benzaldehydes, and phenylacetylenes promoted by FeCl3 under solvent‐free mechanochemical ball milling. Using this protocol, a series of 2,4‐diphenylquinolines were synthesized in good to excellent yield (74–95%) just by washing the resulting reaction mixture with water and recrystallizing in EtOH/H2O without any extraction or column chromatography work‐up.

Solvent-free and room temperature synthesis of 3-arylquinolines from different anilines and styrene oxide in the presence of Al2O3/MeSO3H

A highly efficient, simple and environmentally friendly synthesis of 3-arylquinolines has been developed in the presence of Al2O3/MeSO3H via one-pot reaction of anilines and styrene oxide. This methodology provides very rapid access to 3-arylquinolines in good to excellent yields under solvent-free conditions at room temperature in air.

Organocatalytic Enantioselective Intramolecular Povarov Reaction of Anilines

Key words Povarov reaction - anilines - aza-Diels–Alder reaction - phosphoric acid catalysis - tetrahydroquinolines

Facile one-pot multicomponent synthesis of 1H-pyrazolo[3,4-b]quinolines using L-proline as a catalyst

An efficient protocol for the synthesis of a new series of 1H-pyrazolo[3,4-b]quinolines has been described. The target compounds have been synthesized by one-pot multicomponent reaction of aniline, aromatic aldehydes, and 5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol- 3-one using L-proline as an organocatalyst. Structural diversity and high yields of products, broad scope of aromatic aldehydes, simple operation, and short reaction times have been demonstrated as the advantages of the developed synthetic approach.

Regioselective and Switchable meso-Aminations and Couplings of 5,15-Diarylchlorins.

Controllable chemo- and regiodivergent amination reactions of anilines and chlorins are accomplished by employing different oxidants and substrates, constructing aminated chlorin monomers and dimers with high structural diversity. Importantly, besides preferential 20-meso-position, the oxidative amination was also realized at the inactive 10-meso-position by using phenyliodine bis(trifluoroacetate) (PIFA) and gold(III)-based reagents.

Alum as an efficient catalyst for the multicomponent synthesis of functionalized piperidines

An effective approach to the synthesis of functionalized piperidines via a one-pot multicomponent reaction of aniline, β-ketoester and aldehyde in the presence of alum as an efficient catalyst has been reported. The present procedure offers advantages such as simple workup, short reaction time and offers rapid access to a variety of functionalized piperidines.

Синтез алкилхинолинов реакцией конденсации анилина с фотоокисленными спиртами под действием FeCl3∙6H2O

Синтез алкилхинолинов реакцией конденсации анилина с фотоокисленными спиртами под действием FeCl3∙6H2O

Synthesis, characterization and electrical property of MWCNT-ZnS nanocomposite embedded in polyaniline

PANI/MWCNT-ZnS nanocomposites with different contents of ZnS wt.% have been synthesized by the chemical oxidative in situ polymerization reaction of aniline in the presence of multi-walled carbon nanotube (MWCNT). TEM, XRD, RAMAN and TGA studies have been done for the structural and thermal characterizations of the samples. The particle sizes of ZnS nanoparticles have the values in the range from 3.21 to 5.08 nm. XRD spectrum reveals the co-existence of MWCNT, ZnS in PANI matrix, where ZnS forms a hexagonal structure. TGA result shows that nanocomposite becomes more thermally stable with increase in ZnS content. The dc electrical transport property of PANI/MWCNT-ZnS nanocomposites has been investigated within a temperature range 77 K ⩽ T ⩽ 300 K. The dc conductivity follows a 3D variable range hopping (VRH) model. A large magnetoconductivity change (23.1%) is observed for 2 wt.% ZnS content in PANI/MWCNT-ZnS, which is explained by the wave function shrinkage model.

Sustainable Catalytic Process with a High Eco‐Scale Score for the Synthesis of Five‐, Six‐, and Seven‐Membered Heterocyclic Compounds Using Nanocrystalline Zeolites

AbstractNanocrystalline ZSM‐5 and Beta zeolites were evaluated as catalysts for the one‐pot synthesis of a wide range of five‐, six‐, and seven‐membered heterocyclic compounds. Seven‐membered compounds were prepared by the reaction of o‐phenylenediamine and ketones, whereas five‐membered compounds were obtained when o‐aminothiophenol was reacted with ketones under the same reaction condition. Several other seven‐membered compounds were prepared by the reaction of (E)‐chalcone with o‐phenylenediamine/o‐aminothiophenol, whereas the six‐membered compounds described in this study were prepared by the reaction of o‐phenylenediamine with 2‐bromoacetophenone/2‐hydroxy acetophenone. Two other five‐membered compounds were prepared by the reaction of aniline with benzaldehyde and thioglycolic acid, and the reaction of glycerol with acetone. The mechanisms responsible for the formation of the different products were elucidated based on the results of time‐dependent 1H NMR experiments. To the best of our knowledge, this work represents the first reported systematic assessment of the catalytic activity of nanocrystalline zeolites for the synthesis of heterocyclic compounds. Notably, the catalysts were readily recovered and reused without any considerable decrease in their catalytic activity. The high eco‐scale score and low E‐factor value of this process clearly demonstrate that it represents a green and sustainable synthetic route for the preparation of a wide range of heterocyclic compounds of significant industrial importance.

Role of Mediator and Effects of Temperature on ortho-C-N Bond Fusion Reactions of Aniline Using Ruthenium Templates: Isolation and Characterization of New Ruthenium Complexes of the in-Situ-Generated Ligands.

In this work, ortho-C-N bond fusion reactions of aniline are followed by the use of two different ruthenium mediators. Reaction of aniline with [RuIII(terpy)Cl3] (terpy = 2,2':6',2″-terpyridine) resulted in a trans bis-aniline ruthenium(II) complex [1]+ which upon oxidation with H2O2 produced compound [2]+ of a bidentate ligand, N-phenyl-1,2-benzoquinonediimine, due to an oxidative ortho-C-N bond fusion reaction. Complex [1]+ and aniline (neat) at 185 °C produced a bis-chelated ruthenium complex (3). A previously reported complex [RuII(N-phenyl-1,2-benzoquinonediimine)(aniline)2(Cl)2] (5) undergoes similar oxidation by air at 185 °C to produce complex [3]. A separate chemical reaction between aniline and strongly oxidizing tetra-n-propylammonium perruthenate [(n-pr)4N]+[RuO4]- in air produced a ruthenium complex [4] of a N4-tetraamidophenylmacrocycle ligand via multiple ortho-C-N bond fusion reaction. Notably, the yield of this product is low (5%) at 100 °C but increases to 25% in refluxing aniline. All these complexes are characterized fully by their physicochemical characterizations and X-ray structure determination. From their structural parameters and other spectroscopic studies, complex [2]+ is assigned as [RuII(terpy)(N-phenyl-1,2-benzoquinonediimine)(Cl)]+ whereas complex [4] is described as a ruthenium(VI) complex comprised of a reduced deprotonated N-phenyl-1,2-diamidobenzene and N4-tetraamidophenylmacrocyclic ligand. Complex [2]+ exhibits one reversible oxidation at 1.32 V and one reversible reduction at -0.75 V vs Ag/AgCl reference electrode. EPR of the electrogenerated complexes has revealed that the oxidized complex is a ruthenium(III) complex with an axial EPR spectrum at gav= 2.06. The reduced complex [2], on the other hand, shows a single-line EPR signal at gav= 1.998. In contrast, complex [4] shows two successive one-electron oxidation waves at 0.5 and 0.8 V and an irreversible reduction wave at -0.9 V. EPR studies of the oxidized complexes [4]+ and [4]2+ reveal that oxidations are ligand centered. DFT calculations were employed to elucidate the electronic structures as well as the redox processes associated with the above complexes. Aerial ortho-C-N bond fusion reactions of aniline using two different mediators, viz. [RuIII(terpy)Cl3] and [(n-pr)4N]+[RuO4]-, have been followed. It is found that in the case of oxidizable Ru(III) mediator complex, C-N bond fusion is limited only to dimerization reaction whereas the high-valent Ru(VII) salt mediates multiple C-N bond fusion reactions leading to the formation of a novel tetradentate N4-tetraamidophenylmacrocyclic ligand. Valence ambiguity in the complexes of the resultant redox-active ligands is scrutinized.

A Four-Component Cascade C-H Functionalization/Cyclization/Nucleophilic Substitution Reaction To Construct α-Functionalized Tetrahydroquinolines by the Strategy of in Situ Directing Group Formation.

A four-component cascade C-H functionalization/cyclization/nucleophilic substitution reactions of anilines, carboxylic anhydrides, propenol, and alkohols have been developed by a strategy of in situ directing group formation, affording an efficient and convenient synthesis of α-alkoxyl tetrahydroquinolines from basic starting materials. A plausible mechanism involving rhodium(III) catalytic C-H functionalization and double nucleophilic attacks is proposed. The nucleophilicity order of some alcohols is also obtained for the cascade reaction.

Removal of lead and arsenic ions by a new series of aniline based polyamines

Abstract A new series of aniline based polyamines were produced via mannich polycondensation reaction of aniline, formaldehyde and various alkyldiamines. The synthesized polyamines were characterized by solid 13C NMR, FT-IR and elemental analysis. Crystallinity and Surface morphology was investigated by powder X-ray diffraction and SEM-EDX. Thermal stability was tested by thermogravimetric analysis. Adsorption properties toward lead (II) and Arsenic (V) ions was studied by model solutions at controlled conditions (pH, time, temperature and initial concentration). An-Buta polymer showed higher efficacy toward the removal of lead and arsenic ions and was selected to be used in the treatment of wastewater samples and showed efficient removal % of ∼99% and % 85 for lead (II) and Arsenic (V) ions respectively. The results reveal the high potential of the synthesized polyamines to be potential adsorbents for wastewater treatment.

Investigation of the full reversal of selectivity in the reaction of aniline with 1,3-dichloro-1,3-bis(dimethylamino)vinamidinium salts

Changing the timing of the addition of triethylamine switches this reaction towards the formation of either a quinoline or a malonamidine.