Amination Of Aldehydes Research Articles

ChemInform Abstract: Metal‐Free Reductive Amination of Aldehydes for the Synthesis of Secondary and Tertiary Amines.

AbstractSecondary and tertiary aromatic amines are synthesized by metal‐free one‐pot reductive amination of various aldehydes with primary aromatic amines using benzaldehyde/o‐phenylenediamine as reducing system.

A General and Direct Reductive Amination of Aldehydes and Ketones with Electron-Deficient Anilines

In our ongoing efforts in preparing tool compounds for investigating and controlling the biosynthesis of phenazines, we recognized the limitations of existing protocols for C–N bond formation of electron-deficient anilines when using reductive amination. After extensive optimization, we have established three robust and scalable protocols for the reductive amination of ketones with electron-deficient anilines, by using either BH₃·THF/AcOH/CH₂Cl₂ (method A), with reaction times of several hours, or the more powerful combinations BH₃·THF/TMSCl/DMF (method B) and NaBH₄/TMSCl/DMF (method C), which give full conversions for most substrates within 10 to 25 minutes. The scope and limitations of these reactions have been defined for 12 anilines and 14 ketones.

Synthesis of indolizines through aldehyde–amine–alkyne couplings using metal-organic framework Cu-MOF-74 as an efficient heterogeneous catalyst

A crystalline copper-based metal-organic framework Cu-MOF-74 was synthesized, and was characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR), atomic absorption spectrophotometry (AAS), and nitrogen physisorption measurements. The Cu-MOF-74 exhibited high catalytic activity in the synthesis of indolizines through aldehyde–amine–alkyne three-component coupling transformation and higher than those of other Cu-MOFs such as Cu2(BDC)2(DABCO), Cu3(BTC)2, Cu(BDC), Cu2(NDC)2(DABCO), and Cu4I4(DABCO)2. The reactions could only proceed to produce indolizines in the presence of the solid Cu-MOF catalyst, and contribution from active copper species leached from the solid Cu-MOF-74, if any, was negligible. The Cu-MOF catalyst be recovered and reused several times for the synthesis of indolizines without a significant degradation in catalytic activity. To the best of our knowledge, the synthesis of indolizines using a recyclable heterogeneous catalyst was not previously mentioned in the literature.

Carbon dioxide promoted reductive amination of aldehydes in water mediated by iron powder and catalytic palladium on activated carbon

A mixture of iron powder and catalytic palladium on activated carbon has been developed for reductive amination of various aromatic aldehydes, including 2-pyridinecarboxaldehyde, in water under CO2 atmosphere. The reversible reaction of CO2 with water could form carbonic acid and hydrogen transfer from water to Pd(0) took place with the presence of iron powder, leading to formation of high-active Pd hydrides for the reductive amination process. On the other hand, the reaction system could be inherently neutralized by ready removal of CO2, thus resulting in facile post-processing.

An exploration on the synthesis and bio-applications of derivatives of heterocyclic Mannich bases

The Mannich reaction is a three-component reaction of an aldehyde, a primary or secondary amine and a ketone which is one of the most powerful C-C bond forming reactions in organic synthesis. It leads to β-amino carbonyl compounds, which are useful for the syntheses of nitrogen containing compounds, such as natural products and medicinally relevant compounds. The versatility and potential of these compounds to introduce both functional and structural diversity using the Mannich reaction have stimulated the creativity of chemists. Keeping in view of the importance of this organic moiety in the field of medicine and biology here an attempt has been made to review the synthesis and biological importance of heterocyclic Mannich base derivatives.

Preparation and characterization of epoxy/slag composite for cement slurry applications

ABSTRACTIn this study, epoxy/slag composites (ESCs) were prepared by using diglycidyl ether of bisphenol‐A epoxy resin, water‐quenched granulated blast furnace slag as filler, phenolic aldehyde amine as hardener, and titanate as coupling agent. The properties of ESC, including chemical structure, thermal stability, wetting properties, and morphological structure, were investigated by using Fourier transform infrared spectroscopy, thermogravimetric analysis, a contact angle meter, scanning electron microscopy, and energy dispersive spectrometry. The results show that ESCs possess excellent thermal stability, hydrophilicity, and good compatibility with cement slurry compared to pure epoxy. In addition, the applications of ESC in a cement slurry were also investigated. It was found that the fluidity, free water, fluid loss, and content of Ca(OH)2 decreased, while the compressive strength increased with the incorporation of slag into the epoxy matrix. These features were attributed to the pozzolanic reaction of slag by consumption of Ca(OH)2 to form calcium silicate hydrate (C‐S‐H) gel which contributed more to the compressive strength of set cement. Finally, lightweight cement containing ESCs exhibited high strength without affecting the density of the light cement slurry under curing pressure and at high mixing rate compared with lightweight cement made of floating beads. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43359.

Direct oxidative amination of aromatic aldehydes with amines in a continuous flow system using a metal-free catalyst

Metal-free oxidative amination of aromatic aldehydes with amines in a continuous flow system under mild reaction conditions.

Synthesis of unsaturated secondary amines by direct reductive amination of aliphatic aldehydes with nitroarenes over Au/Al2O3catalyst in continuous flow mode

Unsaturated secondary amines were successfully synthesized by reductive amination of aldehydes with nitroarenes over Au/Al2O3catalyst in a flow reactor.

Direct reductive amination of aldehydes with nitroarenes using bio-renewable formic acid as a hydrogen source

Direct reductive amination of aldehydes with nitroarenes can be carried out efficiently in neat water in the presence of a single phase rutile titania supported gold catalyst using FA as the hydrogen donor.

Facile one-pot tandem reductive amination of aldehydes from nitroarenes over a hierarchical ZSM-5 zeolite containing palladium nanoparticles

Palladium nanoparticles embedded in hierarchical zeolite act as an acid–metal bifunctional catalyst for efficient reductive amination of aldehyde from nitroarenes.

ChemInform Abstract: Highly Chemoselective Reduction of Imines Using a AuNPore/PhMe2SiH/Water System and Its Application to Reductive Amination.

Abstract An unusually strong affinity of unsupported nanoporous gold (AuNPore) towards aldimines and ketimines has been demonstrated. By using PhMe 2 SiH and water as a hydrogen source and AuNPore as a catalyst, ketimines and aldimines can be reduced to the corresponding amines in high chemical yields under mild conditions. This system was also applied to the reductive amination of aldehydes and ketones.

Magnetic nanoparticle-supported phosphine gold(i) complex: a highly efficient and recyclable catalyst for the direct reductive amination of aldehydes and ketones

The direct reductive amination of aldehydes and ketones has been achieved with excellent yields using recyclable magnetic nanoparticle-supported gold(i) catalyst.

Au/TiO2catalyzed reductive amination of aldehydes and ketones using formic acid as reductant

The combination of commercial easily available Au/TiO2as catalyst and cost-effective formic acid as reductant was able to render reductive amination of various carbonyl compounds.

Palladium nanoparticles immobilized on an amine-functionalized MIL-101(Cr) as a highly active catalyst for oxidative amination of aldehydes

Palladium nanoparticles has effectively immobilized onto amine-functionalized MIL-101(Cr) by polyol approach. The resulting Pd/NH2-MIL-101(Cr) acts as a heterogeneous catalyst for oxidative amination of aldehydes under solvent-free conditions.

ChemInform Abstract: In situ Protection and Deprotection of Amines for Iron Catalyzed Oxidative Amidation of Aldehydes.

AbstractCarbon dioxide is found to be the ideal protecting group for the in situ protection and deprotection of amines for the oxidative amination of aldehydes.

Metal-free new synthesis of 1,3-naphthoxazines via intramolecular cross dehydrogenative-coupling reaction of 1-(α-aminoalkyl)-2-naphthols using hypervalent iodine(III) reagent

A series of 1-(α-aminoalkyl)-2-naphthols were synthesized via three-component Betti reaction of β-naphthol, aldehyde, and cyclic secondary amine under reflux conditions. The subsequent reactions of 1-(α-aminoalkyl)-2-naphthols with (diacetoxyiodo)benzene resulted in the formation of 1,3-napthoxazines. This reaction demonstrates the formation of CO bond via cross dehydrogenative-coupling (CDC) under transition metal-free conditions.

Transition-Metal-Free Deacylative Cleavage of Unstrained C(sp(3))-C(sp(2)) Bonds: Cyanide-Free Access to Aryl and Aliphatic Nitriles from Ketones and Aldehydes.

A transition-metal-free deacylative C(sp(3))-C(sp(2)) bond cleavage for the synthetically practical oxidative amination of ketones and aldehydes to nitriles is first described, using cheap and commercially abundant NaNO2 as the oxidant and the nitrogen source. Various nitriles bearing aryl, heteroaryl, alkyl, and alkenyl groups could be smoothly obtained from ketones and aldehydes in high yields, avoiding highly toxic cyanides or transition metals.

Transfer hydrogenative reductive amination of aldehydes in aqueous sodium formate solution

A practical direct reductive amination reaction of aldehydes in aqueous sodium formate solution which produces amines in good yields under mild conditions is described. The amount and strength of the acid additives were critical factors to affect the reaction selectivities. This reductive amination method has great application potential for the synthesis of amine products given the mild conditions, short reaction time, the use of water as a solvent, and the use of benign hydrogen sources.

Polymer-immobilized α,α-bis[bis-3,5-(trifluoromethyl)phenyl]prolinol silyl ether: synthesis and application in the asymmetric α-amination of aldehydes

α , α -Bis[bis-3,5-(trifluoromethyl)phenyl]prolinol silyl ether anchored onto polystyrene was synthesized and tested in asymmetric α -amination of aldehydes. The catalytic activity and enantioselectivity of the immobilized catalyst persist for 3 cycles.

Imine Reductase‐Catalyzed Intermolecular Reductive Amination of Aldehydes and Ketones

AbstractImine reductases (IREDs) have emerged as promising biocatalysts for the synthesis of chiral amines. In this study, the asymmetric imine reductase‐catalyzed intermolecular reductive amination with NADPH as the hydrogen source was investigated. A highly chemo‐ and stereoselective imine reductase was applied for the reductive amination by using a panel of carbonyls with different amine nucleophiles. Primary and secondary amine products were generated in moderate to high yields with high enantiomeric excess values. The formation of the imine intermediate was studied between carbonyl substrates and methylamine in aqueous solution in the pH range of 4.0 to 9.0 by 1H NMR spectroscopy. We further measured the kinetics of the reductive amination of benzaldehyde with methylamine. This imine reductase‐catalyzed approach constitutes a powerful and direct method for the synthesis of valuable amines under mild reaction conditions.