Synthesis of aziridines by electrochemical oxidative annulation of chalcones with primary amines

Tetrahedron Letters, Год журнала: 2021, Номер 87, С. 153413 - 153413

Опубликована: Окт. 18, 2021

Язык: Английский

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Synthesis of N–H Aziridines from Unactivated Olefins Using Hydroxylamine-O-Sulfonic Acids as Aminating Agent

Опубликована: Март 12, 2024

Herein, we presented a practical methodology for the intermolecular aziridination of alkenes, using HOSA as aminating agent, alongside pyridine or piperidine base, within HFIP solvent system. Notably, this approach showcases excellent reactivity, especially with non-activated and facilitates transformation various alkenes substrates, including mono-, di-, tri, tetra-substituted into aziridines moderate to yield. This method presents promising avenue synthesizing from wide range featuring benefits straightforward operation, mild reaction conditions, extensive substrate compatibility, scalability.

Язык: Английский

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Synthesis of N–H Aziridines from Unactivated Olefins Using Hydroxylamine-O-Sulfonic Acids as Aminating Agent

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(9), С. 6263 - 6273

Опубликована: Апрель 23, 2024

Herein, we presented a practical methodology for the intermolecular aziridination of alkenes, using HOSA as aminating agent, alongside pyridine or piperidine base, within HFIP solvent system. Notably, this approach showcases excellent reactivity, especially with nonactivated and facilitates transformation various alkenes substrates, including mono-, di-, tri, tetra-substituted into aziridines moderate to yield. This method presents promising avenue synthesizing from wide range featuring benefits straightforward operation, mild reaction conditions, extensive substrate compatibility, scalability.

Язык: Английский

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Kinetic Resolution of Aziridines Enabled by N‐Heterocyclic Carbene/Copper Cooperative Catalysis: Carbene Dose‐Controlled Chemo‐Switchability

Angewandte Chemie, Год журнала: 2020, Номер 133(6), С. 3305 - 3313

Опубликована: Окт. 26, 2020

Abstract Catalytic kinetic resolution (KR) and dynamic asymmetric transformation (DyKAT) are alternative complementary avenues to access chiral stereoisomers of both starting materials reaction products. The development highly efficient catalytic systems for kinetically controlled processes has therefore been one the linchpins in synthesis. N‐heterocyclic carbene (NHC)/copper cooperative catalysis enabled KR DyKAT racemic N ‐tosylaziridines by [3+3] annulation with isatin‐derived enals, leading enantioenriched ‐tosylaziridine derivatives (up >99 % ee ) a large library spirooxindole high structural diversity stereoselectivity >95:5 d.r., ). Mechanistic studies suggest that NHC can bind reversibly copper catalyst without compromising its activity regulate complex switch chemoselection between DyKAT.

Язык: Английский

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Visible-Light Photocatalytic Barbier-Type Reaction of Aziridines and Azetidines with Nonactivated Aldehydes

Synlett, Год журнала: 2023, Номер 34(12), С. 1385 - 1390

Опубликована: Фев. 21, 2023

Abstract Barbier-type reactions are a classic group of for carbon–carbon bond formation; however, their common use stoichiometric metals restricts widespread application. Considering the ready availability and diversity cyclic amines, we report visible-light photocatalytic reaction aziridines azetidines with nonactivated aldehydes. A series important γ- δ-amino alcohols were synthesized in presence amines as electron donors. Moreover, this transition-metal-free protocol displays mild conditions, broad functional-group tolerance, wide substrate scope. Mechanistic investigations indicated that carbon radicals carbanions might be generated key intermediates.

Язык: Английский

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Synthesis of N–H Aziridines from Unactivated Olefins Using Hydroxylamine-O-Sulfonic Acids as Aminating Agent

Опубликована: Янв. 30, 2024

Herein, we presented a practical methodology for the intermolecular aziridination of alkenes, using HOSA as aminating agent, alongside pyridine or piperidine base, within HFIP solvent system. Notably, this approach showcases excellent reactivity, especially with non-activated and facilitates transformation various alkenes substrates, including mono-, di-, tri, tetra-substituted into aziridines moderate to yield. This method presents promising avenue synthesizing from wide range featuring benefits straightforward operation, mild reaction conditions, extensive substrate compatibility, scalability.

Язык: Английский

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Aziridination via Nitrogen-Atom Transfer to Olefins from Photoexcited Azoxy-Triazenes

Опубликована: Фев. 20, 2024

Herein, we report that readily accessible azoxy-triazenes can serve as nitrogen atom sources under visible light excitation for the phthalimido-protected aziridination of alkenes. This approach eliminates need external oxidants, precious transition metals, and photocatalysts, marking a departure from conventional methods. The versatility this transformation extends to selective both activated unactivated multi-substituted alkenes varying electronic profiles. Notably, process avoids formation competing C–H insertion products. described protocol is operationally simple, scalable, adaptable photoflow conditions. Mechanistic studies support photofragmentation results in generation free singlet nitrene. Furthermore, mild photoredox-catalyzed N–N cleavage protecting group furnish aziridines reported. Our findings contribute advancement sustainable practical methodologies synthesis nitrogen-containing compounds, showcasing potential broader applications synthetic chemistry.

Язык: Английский

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Ammonium Salt‐Catalyzed Ring‐Opening of Aryl‐Aziridines with β‐Keto Esters

European Journal of Organic Chemistry, Год журнала: 2020, Номер 2020(32), С. 5173 - 5177

Опубликована: Июль 15, 2020

We herein report an ammonium salt-catalyzed protocol for the regioselective ring opening of aryl-aziridines with β-keto esters. The reaction gives access to a variety highly functionalized target molecules two consecutive stereo-genic centers and can be rendered enantioselective (up

Язык: Английский

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Microwave-accelerated and efficient synthesis of structurally diverse N-(2,2-diphenylvinyl)-β-oxoamides

Organic & Biomolecular Chemistry, Год журнала: 2021, Номер 19(35), С. 7678 - 7689

Опубликована: Янв. 1, 2021

N-(2,2-Diphenylvinyl)-β-oxoamides are both the structural moiety of biologically active compounds and important synthetic intermediates. Structurally diverse N-(2,2-diphenylvinyl)-β-oxoamides prepared efficiently from 2-diazo-1,3-dicarbonyl N-alkyl-2,2-diphenylaziridines via an electrophilic ring opening reaction under two different conditions reflux microwave irradiation. 2-Diazo-1,3-dicarbonyl undergo Wolff rearrangement heating to generate α-oxoketenes, which electrophilically react with N-alkylaziridines directly produce structurally in good excellent yields Microwave irradiation accelerates obviously efficiently. Both 2-diazo-1,3-diketones alkyl 2-diazo-3-oxoalkanoates work well. The is catalyst-free highly atom economical, involves only loss nitrogen does not require additives. products useful synthons for convenient preparation multisubstituted β-lactam derivatives.

Язык: Английский

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Photocatalytic Carboxylation of C−N Bonds in Cyclic Amines with CO₂ by Consecutive Visible‐Light‐Induced Electron Transfer

Angewandte Chemie, Год журнала: 2023, Номер 135(11)

Опубликована: Янв. 21, 2023

Abstract Visible‐light photocatalytic carboxylation with CO 2 is highly important. However, it still remains challenging for reluctant substrates low reduction potentials. Herein, we report a novel of C−N bonds in cyclic amines via consecutive photo‐induced electron transfer (ConPET). It also the first reductive ring‐opening reaction azetidines, pyrrolidines and piperidines. This strategy practical to transform variety easily available valuable β‐, γ‐, δ‐ ϵ‐amino acids moderate‐to‐excellent yields. Moreover, method features mild transition‐metal‐free conditions, high selectivity, good functional‐group tolerance, facile scalability product derivations. Mechanistic studies indicate that ConPET might be key generating reactive photocatalysts, which enable activation generate carbon radicals carbanions as intermediates.

Язык: Английский

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