Aza‐Michael Reaction: A Decade Later – Is the Research Over?

European Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 26(26)

Published: June 14, 2023

Abstract The 1,4‐conjugated addition of nitrogen centered nucleophiles to electron‐deficient alkenes, historically called the aza‐Michael addition, is one most significant and widely used reactions in modern synthetic organic chemistry. In last decade, great progress has been made this field namely development various catalytic systems. Fundamental advances involve use transition metal catalysts, organocatalysts, enzymes, ionic liquids, Brønsted Lewis acids bases. This Review aims critically analyze results research into aliphatic aromatic amines with Michael acceptors.

Language: Английский

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Fully Biobased Self-Healing and Recyclable Covalent Adaptable Networks Prepared via a Catalyst-Free Aza-Michael Reaction

ACS Applied Polymer Materials, Journal Year: 2024, Volume and Issue: 6(7), P. 3894 - 3908

Published: March 21, 2024

In the present scenario, petroleum resource-based thermoset materials have become an environmental threat due to their permanent cross-linked structure that limits recyclability. To overcome this problem, development of covalent adaptable networks (CANs) containing dynamic bonds has emerged in recent years can be recycled under suitable conditions. However, fully biobased as well recyclable CANs following a green synthetic protocol is yet great challenge and dream toward sustainable environment. With goal, here, we report CAN films from acrylated castor oil (a low-cost vegetable derivative) cystamine diamine) via catalyst-free aza-Michael reaction using disulfide linkage bond. The show excellent thermoself-healing behavior recyclability for at least 10 cycles while maintaining material properties. addition, catalytically degraded, which further reprocessed reconstruct films. Furthermore, are hydrophobic nature, indicating these useful protective surface coating applications. Therefore, proof concept, demonstrate anticorrosive properties film having maximum water contact angle 102.4°, analyzed by polarization method, electrochemical impedance, salt spray fog test corrosive This work provides economical environmentally friendly route develop multifunctional future.

Language: Английский

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Propiolated Castor Oil: A Novel and Highly Versatile Bio-Based Platform for Extremely Fast, Catalyst-, and Solvent-Free Amino-yne Click Reactions

ACS Sustainable Chemistry & Engineering, Journal Year: 2023, Volume and Issue: 11(2), P. 831 - 841

Published: Jan. 3, 2023

The quest for sustainable monomers and "green" synthetic pathways the design, fabrication, modification of various polymers is great importance attracts a deal attention. Here, highly versatile novel bio-based platform was developed by reacting castor oil with propiolic acid performing amino-yne click reactions. Owing to electron-deficient nature esters, reactions were conducted ease at room temperature, in absence any catalyst solvent (as long as amines low-viscosity liquids temperature), within 5 min. Several primary secondary shown react readily platform. Furthermore, thermosets prepared using propiolated multifunctional amines. displayed improved thermal properties elastomer-like mechanical properties.

Language: Английский

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Understanding selectivity of nucleophilic addition to β-formyl-α-haloenoates: A synthetic and theoretical investigation

Tetrahedron, Journal Year: 2024, Volume and Issue: 155, P. 133892 - 133892

Published: Feb. 22, 2024

Language: Английский

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The literature of heterocyclic chemistry, part XXII, 2022

Advances in heterocyclic chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Language: Английский

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One-Pot Alkynylation/Isomerization Cascade of β-Formylated Enoates to Functionalized Ynones

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

Published: Feb. 21, 2025

The previously unknown γ-hydroxy esters bearing both propargylic and allylic alcohol moieties were obtained from β-formylated enoates terminal alkynes. Their easy base-catalyzed isomerization into γ-keto occurred chemoselectively under metal-free conditions. In contrast to the classical two-step synthesis of carbonyl compounds alcohols involving an oxidation-reduction sequence, this protocol provides functionalized ynones in a single step readily available starting materials. Density functional theory calculations performed elucidate plausible mechanism for cascade transformations.

Language: Английский

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Synthesis of New Azetidine and Oxetane Amino Acid Derivatives through Aza-Michael Addition of NH-Heterocycles with Methyl 2-(Azetidin- or Oxetan-3-Ylidene)Acetates

Molecules, Journal Year: 2023, Volume and Issue: 28(3), P. 1091 - 1091

Published: Jan. 21, 2023

In this paper, a simple and efficient synthetic route for the preparation of new heterocyclic amino acid derivatives containing azetidine oxetane rings was described. The starting (N-Boc-azetidin-3-ylidene)acetate obtained from (N-Boc)azetidin-3-one by DBU-catalysed Horner–Wadsworth–Emmons reaction, followed aza-Michael addition with NH-heterocycles to yield target functionalised 3-substituted 3-(acetoxymethyl)azetidines. Methyl 2-(oxetan-3-ylidene)acetate in similar manner, which further treated various (N-Boc-cycloaminyl)amines 3-(acetoxymethyl)oxetane compounds. synthesis diversification novel were achieved through Suzuki–Miyaura cross-coupling corresponding brominated pyrazole–azetidine hybrid boronic acids. structures compounds confirmed via 1H-, 13C-, 15N-, 19F-NMR spectroscopy, as well HRMS investigations.

Language: Английский

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Ag2CO3 catalyzed aza-michael addition of pyrazoles to α, β-unsaturated carbonyl compounds: A new access to N-alkylated pyrazole derivatives

Tetrahedron, Journal Year: 2023, Volume and Issue: 134, P. 133305 - 133305

Published: Feb. 7, 2023

Language: Английский

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Synthesis of Azaspiro Tricyclic Scaffolds through Post‐Ugi Modifications: Scope and Limitation of Aza‐Michael Cyclization

European Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 26(10)

Published: Jan. 11, 2023

Abstract Post‐Ugi modifications offer a great tool to construct functionalized heterocycles in an atom‐economic manner. Using this approach, we have constructed highly azaspiro tricyclic scaffolds that involve Ugi condensation and ipso ‐cyclization followed by aza‐Michael ring closures. Herein, present detailed account of cyclizations with respect substrate scope limitations, along new methods prepare novel scaffolds.

Language: Английский

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Organocatalytic Desymmetric Double Aza-Michael Addition Cascade: Enantioselective Synthesis of Fused Morpholines

Organic Letters, Journal Year: 2024, Volume and Issue: 26(26), P. 5571 - 5576

Published: June 26, 2024

Double aza-Michael addition (DAM) has become an emerging strategy for the construction of two carbon–nitrogen bonds in a single step, which can significantly simplify synthesis N-heterocycles. Hitherto, their asymmetric catalytic genre remains unattempted. Herein, we describe judicious design organocatalytic enantioselective desymmetric double cascade to access series functionalized fused morpholines with excellent yields and diastereo- enantioselectivities. A one-pot telescopic was demonstrated bridged triheterocyclic compound. In addition, scale-up various attractive postsynthetic modifications title products amplify significance current methodology.

Language: Английский

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