Amide Bond Formation Strategies: Latest Advances on a Dateless Transformation

European Journal of Organic Chemistry, Год журнала: 2020, Номер 2020(30), С. 4641 - 4651

Опубликована: Март 17, 2020

The synthesis of amides remains one the most important transformations and it is more frequently performed reactions. In pharmaceutical industry, formation amide group pivotal among in design synthetic plan. This review presents an overview only very recent contributions, published last three years, to highlight latest progress this “dateless” reaction, with a special focus on metal‐free methodologies. New, efficient and/or greener stoichiometric methods, as well catalytic strategies, have been discussed, either for “classic” coupling approach between amine carboxylic acid (or its activated equivalent) or innovative approaches, mainly involving oxidation procedures generate starting from amines.

Язык: Английский

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Amide Bond Activation: The Power of Resonance

Trends in Chemistry, Год журнала: 2020, Номер 2(10), С. 914 - 928

Опубликована: Сен. 21, 2020

Язык: Английский

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Temporary or removable directing groups enable activation of unstrained C–C bonds

Nature Reviews Chemistry, Год журнала: 2020, Номер 4(11), С. 600 - 614

Опубликована: Сен. 21, 2020

Язык: Английский

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Automated iterative Csp3–C bond formation

Nature, Год журнала: 2022, Номер 604(7904), С. 92 - 97

Опубликована: Фев. 8, 2022

Язык: Английский

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Photocatalyzed [2σ + 2σ] and [2σ + 2π] Cycloadditions for the Synthesis of Bicyclo[3.1.1]heptanes and 5- or 6-Membered Carbocycles

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(46), С. 25411 - 25421

Опубликована: Ноя. 7, 2023

We report the use of photocatalysis for homolytic ring-opening carbonyl cyclopropanes. In contrast to previous studies, our approach does not require a metal cocatalyst or strong reductant. The cyclopropanes can be employed both [2σ + 2σ] and 2π] annulation with either alkenes/alkynes bicyclo[1.1.0]butanes, yielding cyclopent-anes/-enes bicyclo[3.1.1]heptanes (BCHs), respectively. BCHs are promising bioisosteres 1,2,4,5 tetra-substituted aromatic rings. Mechanistic including density functional theory computation trapping experiment DMPO, support 1,3-biradical generated from cyclopropane as key intermediate these transformations.

Язык: Английский

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Contemporary Approaches for Amide Bond Formation

Advanced Synthesis & Catalysis, Год журнала: 2023, Номер 365(24), С. 4359 - 4391

Опубликована: Ноя. 7, 2023

Abstract Amide bond construction has garnered significant interest in recent decades due to amides being one of the most prevalent functional groups among bioactive molecules. Out thirty‐seven new drugs approved by FDA 2022, eleven are small molecules containing at least amide bond. Additionally, there nineteen large as drugs, some which have peptide structures, and therefore, also bear bonds. In years, multiple teams embraced challenge developing more efficient methods for formation. This dedication led numerous publications appearing monthly prestigious journals, showcasing advancements this field. The primary goal review is present viable strategies constructing It crucial differentiate between formation synthesis; hence, focus on describing specific forming C(O)−N particular, concentrates developed within last six years. There a particular emphasis approaches that consider thought process when selecting starting materials groups. approach ensures coverage all common chemical transformations yield

Язык: Английский

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Radical 1,2-Nitrogen Migration Cascades of β-Bromo α-Amino Acid Esters to Access β-Amino Acid Motifs Enabled by Cooperative Ni/Diboron Catalysis

ACS Catalysis, Год журнала: 2024, Номер 14(8), С. 5491 - 5502

Опубликована: Март 28, 2024

Amino acid esters serve as crucial intermediates in protein synthesis and common structural elements biologically active natural compounds. Herein, we present an efficient radical cascade reaction involving 1,2-nitrogen migration C(sp2)–H intramolecular cyclization, enabling access to a diverse array of β-amino motifs. Upon cooperative Ni/diboron catalysis, π-system-independent 1,2-N-shift β-bromo α-amino is achieved, which allows the formation two new bonds, including C(sp3)–C(sp2) bond C(sp3)–N bond. The exhibits extensive substrate compatibility high diastereoselectivity proceeds without need for oxidants, toxic initiators, and/or elevated temperatures. It has been observed that diboron compounds both activating reagent inert C–N cleavage/migration reductant Ni catalytic cycle. This sheds light on remote N-functionalities π-systems. cascades followed by intermolecular halogenation or selenation are also demonstrated.

Язык: Английский

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Regiodivergent Ring-Expansion of Oxindoles to Quinolinones

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(7), С. 4301 - 4308

Опубликована: Фев. 9, 2024

The development of divergent methods to expedite structure–activity relationship studies is crucial streamline discovery processes. We developed a rare example regiodivergent ring expansion access two regioisomers from common starting material. To enable this regiodivergence, we identified distinct reaction conditions for transforming oxindoles into quinolinone isomers. presented proved be compatible with variety functional groups, which enabled the late-stage diversification bioactive as well facilitated synthesis drugs and their derivatives.

Язык: Английский

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Transition‐Metal‐Free Activation of Amides by N−C Bond Cleavage

The Chemical Record, Год журнала: 2019, Номер 20(7), С. 649 - 659

Опубликована: Дек. 13, 2019

Abstract The amide bond N−C activation represents a powerful strategy in organic synthesis to functionalize the historically inert linkage. This personal account highlights recent remarkable advances transition‐metal‐free of amides by cleavage, focusing on both (1) mechanistic aspects ground‐state‐destabilization enabling formation tetrahedral intermediates directly from with unprecedented selectivity, and (2) synthetic utility developed transformations. Direct nucleophilic addition enables myriad methods for C−C, C−N, C−O C−S bonds, providing straightforward more synthetically useful alternative acyl‐metals.

Язык: Английский

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Site-specific Umpolung amidation of carboxylic acids via triplet synergistic catalysis

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Июль 30, 2021

Abstract Development of catalytic amide bond-forming methods is important because they could potentially address the existing limitations classical using superstoichiometric activating reagents. In this paper, we disclose an Umpolung amidation reaction carboxylic acids with nitroarenes and nitroalkanes enabled by triplet synergistic catalysis FeI 2 , P(V)/P(III) photoredox catalysis, which avoids production byproducts from stoichiometric coupling A wide range acids, including aliphatic, aromatic alkenyl participate smoothly in such reactions, generating structurally diverse amides good yields (86 examples, up to 97% yield). This strategy opens a method challenging regioselectivity issues between nucleophilic functional groups, complements group compatibility protocols. The synthetic robustness demonstrated late-stage modification complex molecules gram-scale applications.

Язык: Английский

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