Synergistic Pd/Cu-Catalyzed 1,5-Double Chiral Inductions

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(13), P. 9241 - 9251

Published: March 19, 2024

Much attention has been focused on the catalytic asymmetric creation of single chiral centers or two adjacent stereocenters. However, construction nonadjacent stereocenters is significant importance but challenging because lack remote induction models. Herein, based a C═C bond relay strategy, we report synergistic Pd/Cu-catalyzed 1,5-double model. All four stereoisomers target products bearing 1,5-nonadjacent involving both allenyl axial and central chirality could be obtained divergently by simply changing combination catalysts with different configurations. Control experiments DFT calculations reveal novel mechanism 1,5-oxidative addition, contra-thermodynamic η3-allyl palladium shift, conjugate nucleophilic substitution, which play crucial roles in control reactivity, regio-, enantio-, diastereoselectivity. It expected that this strategy may provide general protocol for synthesis structural motifs distant

Language: Английский

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Dinuclear gold-catalyzed divergent dechlorinative radical borylation of gem-dichloroalkanes

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: May 2, 2024

The enormous and widespread use of organoboronic acids has prompted the development innovative synthetic methodologies to meet demands on structural diversity functional group tolerance. existing photoinduced defunctionalization radical borylation, typically focused conversion one C-X bond (X= Br, I, or other leaving group) into only C-B bond. Herein, we disclose a divergent dechloroborylation reaction enabled by dinuclear gold catalysis with visible light irradiation. A wide range structurally diverse alkyl boronic, α-chloroboronic, gem-diboronic esters can be synthesized in moderate good yields (up 92%). Its robustness is further demonstrated preparative scale applied late-stage diversification complex molecules. process hinges C-Cl relay activation readily available gem-dichloroalkanes through inner-sphere electron transfer, overcoming redox potential limits unreactive chlorides.

Language: Английский

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Ligand-Controlled, Nickel-Catalyzed Stereodivergent Construction of 1,3-Nonadjacent Stereocenters

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(22), P. 15453 - 15463

Published: May 25, 2024

In contrast to the asymmetric synthesis of molecules with a single stereocenter or 1,2-adjacent stereocenters, simultaneous construction acyclic 1,3-nonadjacent stereocenters via catalyst in an enantioselective and diastereoselective manner remains formidable challenge. Here, we demonstrate diastereodivergent through Ni-catalyzed reductive cyclization/cross-coupling alkene-tethered aryl bromides α-bromoamides, which represents major remaining stereochemical challenge cyclization/difunctionalization alkenes. Using Ming-Phos as ligand, diverse set oxindoles containing were obtained high levels enantio- diastereoselectivity. Mechanistic experiments density functional theory calculations indicate that magnesium salt plays key role controlling Furthermore, another complementary stereoisomeric products constructed from same starting materials using Ph-Phox ligand.

Language: Английский

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PolyBorylated Alkenes as Energy‐Transfer Reactive Groups: Access to Multi‐Borylated Cyclobutanes Combined with Hydrogen Atom Transfer Event

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(25)

Published: April 11, 2024

Abstract While polyborylated alkenes are being recognized for their elevated status as highly valuable reagents in modern organic synthesis, allowing efficient access to a diverse array of transformations, including the formation C−C and C‐heteroatom bonds, potential energy‐transfer reactive groups has remained unexplored. Yet, this holds key generating elusive biradical species, which can be captured by olefins, thereby leading construction new highly‐borylated scaffolds. Herein, we report designed strategy photosensitized [2+2]‐cycloadditions poly‐borylated with various olefins enabling regioselective synthesis cyclobutane motifs, 1,1‐di‐, 1,1,2‐tri‐, 1,1,2,2‐tetra‐borylated cyclobutanes. In fact, these compounds belong family that presently lacks synthetic pathways. Interestingly, when α‐methylstyrene was used, reaction involves an interesting 1,5‐hydrogen atom transfer (HAT). Mechanistic deuterium‐labeling studies have provided insight into outcome process. addition, cyclobutanes then demonstrated useful selective oxidation processes resulting cyclobutanones γ‐lactones.

Language: Английский

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Stereodivergent Construction of 1,5/1,7‐Nonadjacent Tetrasubstituted Stereocenters Enabled by Pd/Cu‐Cocatalyzed Asymmetric Heck Cascade Reaction

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(35)

Published: May 16, 2024

Abstract The construction of chiral motifs containing nonadjacent stereocenters in an enantio‐ and diastereoselective manner has long been a challenging task synthetic chemistry, especially with respect to their stereodivergent synthesis. Herein, we describe protocol that enables the 1,5/1,7‐nonadjacent tetrasubstituted through Pd/Cu‐cocatalyzed Heck cascade reaction. Notably, C=C bond relay strategy involving shift π‐allyl palladium intermediate was successfully applied asymmetric 1,7‐nonadjacent stereocenters. current method allows for efficient preparation molecules bearing two privileged scaffolds, oxindoles non‐natural α‐amino acids, good functional group tolerance. full complement four stereoisomers products could be readily accessed by simple combination metal catalysts different enantiomers.

Language: Английский

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Simultaneous Stereoinvertive and Stereoselective C(sp³)–C(sp³) Cross-Coupling of Boronic Esters and Allylic Carbonates

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(20), P. 13719 - 13726

Published: May 9, 2024

With increasing interest in constructing more three-dimensional entities, there has been growing cross-coupling reactions that forge C(sp3)–C(sp3) bonds, which leads to additional challenges as it is not just a difficult bond construct but issues of stereocontrol also arise. Herein, we report the stereocontrolled enantioenriched boronic esters with racemic allylic carbonates enabled by iridium catalysis, leading formation bonds single or vicinal stereogenic centers. The method shows broad substrate scope, enabling primary, secondary, and even tertiary be employed, can used prepare any four possible stereoisomers coupled product chiral new method, combines simultaneous enantiospecific reaction nucleophile enantioselective electrophile process, offers solution for stereodivergent two C(sp3) fragments.

Language: Английский

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Chemoselective and Stereoselective Allylation of Bis(alkenyl)boronates

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(36)

Published: May 23, 2024

Bis(alkenyl)boronates react with optically active Ir(π-allyl) species in a process that involves allylation of the more substituted olefin and 1,2-metalate shift less olefin. The method constructs valuable enantioenriched tertiary allylic boronic esters high chemoselectivity, enantioselectivity diastereoselectivity. Allylic functionalization reactions transform 1,3-stereodiad to 1,5- 1,6-stereochemical relationships.

Language: Английский

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Merging Organocatalysis with 1,2-Boronate Rearrangement: A Lewis Base-Catalyzed Asymmetric Multicomponent Reaction

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(40), P. 27305 - 27311

Published: Sept. 24, 2024

Catalytic asymmetric multicomponent 1,2-boronate rearrangements provide a practical approach for synthesizing highly valuable enantioenriched boronic esters. When applied to alkenyl or heteroaryl boronates, these reactions have relied mainly on transition-metal catalysis. Herein, we present an organocatalytic, Lewis base-catalyzed rearrangement, involving indoles, esters, and Morita-Baylis-Hillman carbonates, leading enantioenriched, substituted indole indoline derivatives. Using cinchona alkaloid-based catalysts, high selectivity has been achieved, enabling expansion of the chemical space around pharmaceutically relevant

Language: Английский

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Catalytic Selective Functionalization of Poly(organoborons)^†

Chinese Journal of Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 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.

Language: Английский

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Asymmetric synthesis of atropisomers featuring cyclobutane boronic esters facilitated by ring-strained B-ate complexes

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Dec. 30, 2024

The strain-release-driven reactions of bicyclo[1.1.0]butanes (BCBs) have received significant attention from chemists. Notably, 1,2-migratory enabled by BCB-derived B-ate complexes effectively complement the initiated common BCBs. desired products are particularly valuable for late-stage transformations due to presence C-B bond. However, asymmetric mediated boronate progressed slowly. In this study, we develop an synthesis atropisomers featuring cis-cyclobutane boronic esters facilitated 1,2-carbon or boron migration ring-strained complexes, achieving high enantioselectivity. reaction is compatible with various aryl, alkenyl, alkyl and B

Language: Английский

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