Ir‐Catalyzed Enantioselective Synthesis of gem‐Diborylalkenes Enabled by 1,2‐Boron Shift

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(32)

Опубликована: Июнь 15, 2023

Abstract Asymmetric cross‐couplings based on 1,2‐carbon migration from B‐ate complexes have been developed efficiently to access valuable organoboronates. However, enantioselective reactions triggered by 1,2‐boron shift remained be unaddressed synthetic challenge. Here, Ir‐catalyzed asymmetric allylic alkylation enabled was developed. In this reaction, we disclosed that excellent enantioselectivities were achieved through an interesting dynamic kinetic resolution (DKR) process of carbonates at the elevated temperature. Notably, highly (bis‐boryl)alkenes array diversifications versatile molecules. Extensive experimental and computational studies conducted elucidate reaction mechanism DKR clarify origin enantioselectivities.

Язык: Английский

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Asymmetric Synthesis of Chiral 1,2‐Bis(Boronic) Esters Featuring Acyclic, Non‐Adjacent 1,3‐Stereocenters

Angewandte Chemie International Edition, Год журнала: 2023, Номер 63(5)

Опубликована: Дек. 15, 2023

The construction of acyclic, non-adjacent 1,3-stereogenic centers, prevalent motifs in drugs and bioactive molecules, has been a long-standing synthetic challenge due to acyclic nucleophiles being distant from the chiral environment. In this study, we successfully synthesized highly valuable 1,2-bis(boronic) esters featuring nonadjacent 1,3-stereocenters. Notably, reaction selectively produces migratory coupling products rather than alternative deborylative allylation or direct byproducts. This approach introduces new activation mode for selective transformations gem-diborylmethane asymmetric catalysis. Additionally, found that other gem-diborylalkanes, previously challenging steric hindrance, also participated reaction. incorporation 1,2-bis(boryl)alkenes facilitated diversification alkenyl two boron moieties our target compounds, thereby enabling access broad array versatile molecules. DFT calculations were performed elucidate mechanism shed light on factors responsible observed excellent enantioselectivity diastereoselectivity. These determined arise ligand-substrate repulsions syn-addition transition state.

Язык: Английский

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Decarboxylation of β-boryl NHPI esters enables radical 1,2-boron shift for the assembly of versatile organoborons

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Сен. 14, 2023

In recent years, numerous 1,2-R shift (R = aliphatic or aryl) based on tetracoordinate boron species have been well investigated. the contrary, corresponding radical migrations, especially 1,2-boryl for construction of organoborons is still in its infancy. Given paucity and significance such strategies chemistry, it urgent to develop other efficient alternative synthetic protocols enrich these underdeveloped 1,2-boron before their fundamental potential applications could be fully explored at will. Herein, we demonstrated a visible-light-induced photoredox neutral decarboxylative cross-coupling reaction, which undergoes give translocated C-radical further capture versatile acceptors. The mild reaction conditions, good functional-group tolerance, broad β-boryl NHPI esters scope as acceptors make this protocol applicable modification bioactive molecules. It can expected that methodology will very useful tool an strategy primary via novel mode.

Язык: Английский

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Visible‐Light‐Induced Domino Cyclization to Access Pyrido[2,3‐d]pyrimidine‐2,4‐diones via a Radical‐Polar Crossover Reaction

Chinese Journal of Chemistry, Год журнала: 2024, Номер 42(19), С. 2346 - 2350

Опубликована: Май 27, 2024

Comprehensive Summary Catalytic and green strategies for the synthesis of privileged scaffolds are synthetically appealing. We now report a radical‐polar crossover (RPC)‐enabled three‐component cyclization bromodifluoroalkyls with enaminones 6‐aminouraciles via visible‐light‐induced domino cyclization. The reaction exhibited broad substrate scope (> 40 examples) including complex molecules, which highlighted utility this strategy construction library bioactive analogs.

Язык: Английский

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Fluoroalkyl Iodides in Fluoroalkylative Difunctionalization of C−C Multiple Bonds

Advanced Synthesis & Catalysis, Год журнала: 2023, Номер 365(13), С. 2092 - 2125

Опубликована: Май 16, 2023

Abstract Fluorinated alkyl iodides serve as a convenient and inexpensive source of fluoroalkyl radicals that can readily undergo addition to the C−C unsaturated bonds alkynes alkenes which is foundation for variety useful synthetic protocols. Since 2010 this field has witnessed huge progress in several respects. First portfolio fluorinated was extended beyond only simple perfluoroalkyl (C n F 2n+1 I). In particular, employment iododifluoro−methyl‐ carbonyls phosphonates enabled facile installation medicinally relevant difluoromethylene motif. Secondly, from conceptual point view, novel strategies activation towards radical formation have been introduced, relying on electron donor‐acceptor (EDA) complexes, photoredox catalysis, frustrated Lewis pairs transition metal complementing prior approaches based heat UV induced C−I homolysis, initiators, transfer processes. Based these range fluoroalkylative transformations systems added classical iodoperfluoroalkylation. Broadly applicable protocols fluoroalkylation hydrofluoroalkylation, well more sophisticated, complexity‐building methods fluoroalkylation‐annulation tandem multicomponent fluoroalkylations with concomitant another functionality recently disclosed. This review summarizes achieved since reactivity emphasis placed above‐mentioned advances.

Язык: Английский

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Transition-metal-free C(sp2)–C(sp3) cross-coupling of α-(pseudo)halo aliphatic ketones with boronic acids via a 1,4-metallate shift

Nature Synthesis, Год журнала: 2023, Номер 2(12), С. 1211 - 1221

Опубликована: Авг. 3, 2023

Язык: Английский

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Synergistic Brønsted Base/Photoredox‐Catalyzed Three‐Component Coupling with Malonates to Synthesize δ‐Hydroxy Esters and δ‐Keto Esters

Chinese Journal of Chemistry, Год журнала: 2024, Номер 42(9), С. 957 - 962

Опубликована: Янв. 18, 2024

Comprehensive Summary Multicomponent alkene 1,2‐dicarbofunctionalizations (DCFs) have emerged as a powerful strategy to rapidly incorporate both two carbon subunits across one C—C double bond in step for enhancing molecular complexity and diversity. To the best of our knowledge, there is only report on photoredox‐catalyzed three‐component DCFs with malonates through radical−radical cross‐coupling, while radical‐polar crossover (RPC)‐type were still rare. Herein, we describe redox‐neutral RPC‐type 1,2‐dialkylation styrenes aldehydes synergistic Brønsted base/photoredox catalysis system. This transition‐metal‐free provides an efficient clean approach broad variety δ‐hydroxy esters also features exceptionally mild conditions, wide compatibility substrate scope functional groups, high atomic economy. Moreover, 1,2‐alkylacylation from same starting materials was achieved one‐pot manner such coupling subsequent two‐electron oxidation process, providing set δ‐keto interest pharmaceutical research.

Язык: Английский

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Catalytic Selective Functionalization of Poly(organoborons)^†

Chinese Journal of Chemistry, Год журнала: 2024, Номер unknown

Опубликована: Сен. 28, 2024

Comprehensive Summary Organoborons are commonly used building blocks for rapidly increasing molecular complexity. Although significant progress has been made in the selective functionalization of mono‐organoborons, site‐selective poly(organoborons) attracted substantial interest organic synthesis, pharmaceuticals, and agrochemicals due to presence multiple potential reaction sites. This review discusses various activation modes target C–B bond, with diverse transformations being achieved both a efficient manner. Recent advances catalytic 1, n ‐diboronates through ionic radical pathways highlighted. Furthermore, we summarize existing challenges future research directions this field. Key Scientists In 1993, Suzuki, Miyaura coworkers developed pioneering example arylation towards cis‐1,2‐bis(boryl) alkenes, marking inception The Morken group contributions asymmetric diboration alkenes realized elegant these compounds since 2004. 2016, Fernández colleagues internal bond tri(boronates). Since 2019, Aggarwal Giese‐type addition at more substituted 1,2‐bis(boronic) esters photoredox catalysis. controllable regiodivergent alkynylation 1,3‐bis(boronic) was by Gao 2023. Recently, Qin conducted on programmable late‐stage bridge‐substituted bicyclo[1.1.1]pentane (BCP) bis‐boronates. 2013, stereoselective have several groups, including those led Chen. summarizes latest most developments field 1993.

Язык: Английский

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Palladium-catalyzed cross-coupling of gem-difluorocyclopropanes with gem-diborylalkanes: facile synthesis of a diverse array of gem-diboryl-substituted fluorinated alkenes

RSC Advances, Год журнала: 2025, Номер 15(13), С. 10265 - 10272

Опубликована: Янв. 1, 2025

This study introduces an efficacious palladium-catalyzed method for the regioselective and stereoselective cross-coupling of gem -difluorinated cyclopropanes with array -diborylalkanes under mild reaction conditions.

Язык: Английский

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Synthesis of α-Haloboronates by the Halogenation of gem-Diborylalkanes via Tetracoordinate Boron Species

Organic Letters, Год журнала: 2023, Номер 25(16), С. 2928 - 2933

Опубликована: Апрель 18, 2023

α-Haloboronates have a wide range of applications in organic chemistry as synthetic synthons; however, traditional methods α-haloboronates are harsh and complicated. Herein, we used nBuLi the nucleophilic reagent to attack boron atom gem-diborylalkanes form tetracoordinate species successfully achieved α-chloroboronates α-bromoboronates with readily accessible electrophilic halogen reagents (NCS NBS). The reaction is transition-metal-free features broad substrate scope diversified valuable products.

Язык: Английский

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