Vitamin B₁₂ and Micellar Solution Enable Regioselective Ring Opening of Epoxides and Aziridines with Electrophilic Olefins

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: May 23, 2025

Vitamin B12, a water-soluble cobalt complex, is inherently predisposed to catalyze reactions under aqueous conditions. Despite its potential, adopting this strategy for transformations of hydrophobic reagents has been challenging, because their low solubility. Here, we demonstrate that vitamin B12 promotes the reaction epoxides and aziridines with electrophilic olefins in micellar system. The desired products are obtained efficiently fully regioselective manner. This green catalytic approach further advances use sustainable catalysis providing valuable method synthesize important intermediates.

Language: Английский

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Telescoped Flow Synthesis of Azacyclic Scaffolds Exploiting the Chromoselective Photolysis of Vinyl Azides and Azirines

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(38)

Published: May 8, 2024

An efficient chromoselective photochemical process is presented for the synthesis of 2H-azirines and 1,3-diazabicylo[3.1.0]hex-3-enes from readily available vinyl azides. The method exploits continuous flow photochemistry to enable safe consumption hazardous azide group provides uniform irradiation using high-power LEDs at 365-450 nm. Additionally, a scaled telescoped has been developed providing access drug-like 1,6-dihydropyrimidines pyrimidines via integrated ring-expansion oxidation reactions. Given prevalence various azacyclic targets in pharmaceutical, agrochemical materials applications it anticipated that this methodology will further exploitations these important scaffolds.

Language: Английский

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Synthesis of Azirinyl Ethynyl Ketones and Their Use in the Preparation C(O)C≡CR-Substituted NH-Pyrroles/NH-Imidazoles and Azole–Azine/Azole–Azole Heterocyclic Hybrids

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 24, 2025

Azirinyl-substituted conjugated ynones were first synthesized by the reaction of lithiated acetylenes with 2H-azirine-2-carbonyl chlorides. Azirinyl ethynyl ketones containing only a C(O)C≡CR substituent at position 2 azirine ring are good precursors for obtaining α-C(O)C≡CR substituted NH-pyrroles and 5-[C(O)C≡CR]-substituted NH-imidazoles, reacting selectively moiety 1,3-diketones arylamidines, respectively. Various N-heterocyclic hybrids (pyrrole-pyrimidine, imidazole-pyrimidine, pyrrole-isoxazole, imidazole-isoxazole, pyrimidine-pyrrole-thiophene, pyrrole-pyrimidine-thiophene, imidazole-pyrimidine-thiophene, isoxazole-pyrrole-thiophene) have been prepared based on orthogonal or domino reactions an moieties azirinyl ketones.

Language: Английский

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Ionic Liquid-Assisted Approaches in the Synthesis of Nitrogen-Containing Heterocycles: A Focus on 3- to 6-Membered Rings

Journal of Ionic Liquids, Journal Year: 2025, Volume and Issue: unknown, P. 100146 - 100146

Published: March 1, 2025

Language: Английский

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Photoreactivity of 1-azidostyrene and 3-phenyl-2H-azirine in acetonitrile and cryogenic matrices

Journal of Photochemistry and Photobiology A Chemistry, Journal Year: 2025, Volume and Issue: unknown, P. 116427 - 116427

Published: April 1, 2025

Language: Английский

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Cyclic Bifunctional Reagents Enabling a Strain-Release-Driven Formal [3 + 2] Cycloaddition of 2H-Azirines by Cascade Energy Transfer

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: April 10, 2025

The energy transfer (EnT)-catalyzed ring opening and further decarboxylation of isoxazole-5(4H)-ones enables the in situ generation strained 2H-azirines. Subsequent selective C(sp2)-C(sp3) bond cleavage azirine intermediate allows a formal [3 + 2] cycloaddition with wide range electrophiles, unlocking access to valuable pyrroline-type moieties. Mechanistic experiments combination density functional theory (DFT) calculations revealed unique nature EnT-cascade process for three-membered aza-cycle while providing insight into regio- diastereoselectivity annulation. This mild straightforward method ensures rapid construction highly substituted cyclic imines, which can be easily converted pyrrolidines, fused oxaziridines, biologically relevant β-amino acid precursors.

Language: Английский

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Photochemical Synthesis and Ring‐Opening of Aziridines and Epoxides: State‐of‐the‐Art

ChemPhotoChem, Journal Year: 2024, Volume and Issue: 8(9)

Published: May 13, 2024

Abstract The development of greener methods for the preparation three‐membered rings has increased in last decade, not only due to their biological activity but also ring strain those heterocycles that make them useful precursors more complex molecules. In this work, visible‐light‐promoted synthesis and ring‐opening aziridines epoxides, reported five years, were reviewed. Both homogeneous heterogeneous catalysts discussed and, addition, plausible mechanism pathways highlighted.

Language: Английский

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Employing Metadynamics to Predict the Membrane Partitioning of Carboxy-2H-Azirine Natural Products

Published: April 16, 2024

Natural products have diverse chemical structures and biological activities which often serve as sources of new therapeutic agents. Those containing a carboxy-2H-azirine moiety are an exciting target for investigation due in part to the broad-spectrum antimicrobial activity these compounds significant space novel development offered by this unique scaffold. The moiety, including those appended well-characterized scaffolds, is understudied, creates challenge understanding potential modes inhibition. In particular, some known natural product carboxy-2H-azirines long hydrophobic tails, might lead amphipathicity implicate them membrane associated processes. Metadynamics effective method calculating free energy changes with embedding study, we examined small set products, analogs alkyl chains, geometric isomers, one comprising simple core. We compared physiochemical properties established embedders similar scaffolds. This was intended isolate group understand molecular influences on partitioning. To accomplish this, developed force field 2H-azirine functional performed metadynamics simulations partitioning into model (75 % POPE, 25 POPG) from aqueous solution. determine that likely hydrophilic, imbuing chain binding molecules they were compared. For analogs, headgroup stays within 1 nm phosphate layer, while lacking partitions completely

Language: Английский

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Reaction Course Dependent Regiospecific Transformation of 4‐Azido‐Coumarin into Coumarin C3‐C4 Fused Imidazole and 5‐Substituted‐1,4‐Benzodiazepine Scaffolds

European Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: June 19, 2024

Abstract Herein, we report an efficient route for coumarin C3‐C4 fused imidazole scaffolds via indium chloride‐mediated single‐step transformation of 4‐azido‐coumarin with amines/aldehydes and 5‐substituted‐1,4‐benzodiazepine 1,2‐azide‐nitrogen migration through two‐step sequential synthesis the transitory intermediacy 2,3‐bridged‐2 H ‐azirine. A plausible mechanistic pathway has been proposed from control/entrapment experiments 1 H‐NMR studies. This protocol provides reaction condition‐dependent product selectivity, structural diversification, excellent yields.

Language: Английский

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Transition‐Metal Catalyzed Enantioselective Aziridination Reaction: Recent Development in Catalysis and Future Perspectives

ChemCatChem, Journal Year: 2024, Volume and Issue: 16(21)

Published: July 16, 2024

Abstract Chiral aziridines are important motifs in natural products and biologically significant compounds, as well one of the most valuable versatile building blocks for construction diverse chiral functionalized amines. Because importance aziridines, various novel transition‐metal‐based catalytic systems synthetic strategies have been established to investigate highly effective enantioselective aziridination process. This review outlined recent advances made transition‐metal catalyzed reactions, challenges potential field at current stage.

Language: Английский

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