User‐Friendly Copper‐Catalysed Reduction of Azides to Amines

Pimpasri, Chaleena; White, Andrew J. P.; Díez‐González, Silvia

doi:10.1002/ajoc.201900555

Cited by 5 publications

(5 citation statements)

References 47 publications

(16 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Given the fact that the azide reduction to an amine proceeds together with the deposition of Cu over the course of the reaction, it removes one equivalent of available azide from the mixture and alters the Cu-azide ratio. In addition, the Cu-mediated amination proceeds via reactive Cu-nitrenes, ,− and the mass recovery was nearly identical when the catalyst was prepared with and without the presence of BrPhAc . The completion of the amination, to 1,4-acetylaniline, was confirmed by 1 H NMR spectroscopy in the current experiment with BrPhAc , which confirms that the reaction is not inhibited by the presence of CB.…”

Section: Resultsmentioning

confidence: 87%

Azide-Assisted Growth of Copper Nanostructures and Their Application as a Carbon Supported Catalyst in Two-Step Three-Component Azide–Alkyne Cycloadditions

Roemer

Lewis

2023

Langmuir

View full text Add to dashboard Cite

Copper nanostructures were obtained from the reduction of Cu(I) under mild conditions in ethanol/water using sodium-L-ascorbate and sodium azide while performing an amination reaction. When the halobenzene substrate was reacted in the presence of a bulk carbon black (CB) support, clustered copper sub-micrometer particles (SMPs) and microparticles (MPs) form. The growth conditions of the MPs were optimized, and the supported nanostructures were isolated and characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, thermogravimetry, and inductively-coupled plasma mass spectrometry. The particles are mobile and supported within the CB matrix and proved to be active catalysts in the azide−alkyne cycloaddition (CuAAC). The catalytic competency of the particles was assessed in a two-step three-component azide−alkyne cycloaddition of benzyl bromide, sodium azide, and phenylacetylene as a model reaction. The reaction conditions were optimized, and the optimized conditions were applied for the synthesis of triazole compounds with varying levels of functionalization. The recyclability of the catalysts was investigated, depletion modes were discussed, and the conditions were fine-tuned to reach good recyclability. This demonstrates the broader applicability of the SMPs/MPs as CuAAC-catalyst and its limitations.

show abstract

Section: Resultsmentioning

confidence: 87%

Azide-Assisted Growth of Copper Nanostructures and Their Application as a Carbon Supported Catalyst in Two-Step Three-Component Azide–Alkyne Cycloadditions

Roemer

Lewis

2023

Langmuir

View full text Add to dashboard Cite

show abstract

“…The most prominent peaks in the high-resolution mass spectrum (Supporting Information, page S10) are assigned to the structures T1−T3 shown in Scheme 1. It has been previously suggested that similar copper-mediated in situ amination reactions proceed via highly reactive nitrene intermediates, 24,25,36 which may be copper-stabilized. 36 We have proposed a similar pathway for the amination in EtOH/ water.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

“…Based on these data, we propose amine formation proceeds via nitrene intermediates, in agreement with earlier reports of comparable systems (Scheme 2a). 24,25,36 Initially, aromatic halogen−azide exchange occurs, followed by elimination of N 2 generating a, possibly Cu-stabilized, nitrene. It reacts in a stepwise manner with available hydrogens to afford the amine.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

“…An alternative strategy for the amination of haloaryls with ammonia is the amination with azides via aryl azides as intermediates (Figure ). This can be achieved via transition metal-catalyzed, − transition metal-mediated, and glucose-mediated reactions. Efficiencies can be achieved with the reaction of aryl halides with sodium azide using flow chemistry over a copper column …”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Copper(I) Chloride Mediated Amination of Halobenzenes via Azides: Scope, Mechanistic Aspects, and C–C Cleavage Reactions

2023

View full text Add to dashboard Cite

Selective azidation−amination of long-chain alkanoyl halobenzenes with sodium azide, promoted by copper(I) chloride, is reported. The protocol is, apart from CuCl and NaN 3 , additive free and allows the isolation of versatile amine−azides. Alkyl cleavage occurs as a side reaction through an unusual Schmidt-type azide insertion adjacent to the carbonyl group, forming alkyl nitriles possibly via radical pathways. Mechanistic studies involving 15 N labeling experiments and test substrates indicate that the reaction occurs via 1-azido-4-alkanoyl benzenes. The amination is applicable for substrates with electron-withdrawing groups and proceeds under mild conditions. The mechanism of the amine formation involves nitrenes. Intermediates were trapped by carrying out the reaction in the presence of the 2,2,6,6-(tetramethylpiperidin-1-yl)oxyl stable radical and characterized by high-resolution mass spectrometry. The intermediates are consistent with earlier mechanistic proposals.

show abstract

“…Subsequent catalytic reduction of the nitro group yields the desired amino group. Reducing an azide group at the C‐7 position [42–44] can also produce amine moieties. Azides are essential intermediates in medicinal chemistry, enabling the synthesis of heterocycles such as triazoles and tetrazoles, allowing quinolone‐triazole or tetrazole hybrids to be generated [45–48] …”

Section: Resultsmentioning

confidence: 99%

Synthesis and Anticancer Activity of 1‐(Ethyl/Methyl)‐7‐(p‐Methoxybenzyl Amino) and 7‐Amino‐6‐Fluoroquinolone‐Boron Difluoride Complexes

Hernández‐López,

Tejada‐Rodríguez,

Leyva‐Ramos

et al. 2023

ChemistrySelect

View full text Add to dashboard Cite

Novel 1‐(ethyl/methyl)‐7‐(p‐methoxybenzyl amino) and 7‐amino‐6‐fluoroquinolone‐boron difluoride complexes were synthesized, and their biological activity was studied, comparing the influence of the nature of 7‐substituent as well as N‐1 substituent. The quinolone compounds were characterized by IR, UV‐Vis, 1H, 13C{1H} and 19F{1H} NMR, and mass spectrometry. The antiproliferative effect of the new fluoroquinolone‐boron complexes in breast cancer (BC) derived cell lines MCF‐7 and SKBR‐3 was investigated. Compounds 9 b and 9 a showed antiproliferative in MCF‐7 cells, and 9 b, 11 b, 9 a, 7 a, 7b and 8 a showed similar effects in SKBR‐3 cells. Derivatives with p‐methoxybenzyl amino moieties at C‐7 and an ethyl or methyl group at N‐1 in the fluoroquinolone ring (9 a and 9 b) were the more efficient in both breast cancer cell lines. In addition, an 8‐nitro group to the fluoroquinolone (11 b) improved activity against SKBR‐3 cell proliferation. These compounds represent potential drug candidates for breast cancer treatment.

show abstract

User‐Friendly Copper‐Catalysed Reduction of Azides to Amines

Cited by 5 publications

References 47 publications

Azide-Assisted Growth of Copper Nanostructures and Their Application as a Carbon Supported Catalyst in Two-Step Three-Component Azide–Alkyne Cycloadditions

Azide-Assisted Growth of Copper Nanostructures and Their Application as a Carbon Supported Catalyst in Two-Step Three-Component Azide–Alkyne Cycloadditions

Copper(I) Chloride Mediated Amination of Halobenzenes via Azides: Scope, Mechanistic Aspects, and C–C Cleavage Reactions

Synthesis and Anticancer Activity of 1‐(Ethyl/Methyl)‐7‐(p‐Methoxybenzyl Amino) and 7‐Amino‐6‐Fluoroquinolone‐Boron Difluoride Complexes

Contact Info

Product

Resources

About