Recent Advances in C–H Functionalisation through Indirect Hydrogen Atom Transfer

Molecules, Год журнала: 2023, Номер 28(16), С. 6127 - 6127

Опубликована: Авг. 18, 2023

The functionalisation of C–H bonds has been an enormous achievement in synthetic methodology, enabling new retrosynthetic disconnections and affording simple equivalents for synthons. Hydrogen atom transfer (HAT) is a key method forming alkyl radicals from substrates. Classic reactions, including the Barton nitrite ester reaction Hofmann–Löffler–Freytag reaction, among others, provided early examples HAT. However, recent developments photoredox catalysis electrochemistry have made HAT powerful tool capable introducing wide range functional groups into bonds. Moreover, greater mechanistic insights stimulated development increasingly site-selective protocols. Site-selectivity can be achieved through tuning electron density at certain using additives, judicious choice reagent, solvent system. Herein, we describe latest methods functionalizing C–H/Si–H/Ge–H indirect between 2018–2023, as well critical discussion reagents, aspects, substrate scopes, background contexts

Язык: Английский

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Hydrogen-bond-acceptor ligands enable distal C(sp3)–H arylation of free alcohols

Nature, Год журнала: 2023, Номер 622(7981), С. 80 - 86

Опубликована: Сен. 6, 2023

Язык: Английский

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Ligand‐Enabled Palladium(II)‐Catalyzed Enantioselective β‐C(sp³)−H Arylation of Aliphatic Tertiary Amides**

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(17)

Опубликована: Март 5, 2023

Amide is one of the most widespread functional groups in organic and bioorganic chemistry, it would be valuable to achieve stereoselective C(sp3 )-H functionalization amide molecules. Palladium(II) catalysis has been prevalently used C-H activation chemistry past decades, however, due weakly-coordinating feature simple amides, challenging their direct with enantiocontrol by PdII catalysis. Our group developed sulfoxide-2-hydroxypridine (SOHP) ligands, which exhibited remarkable activity Pd-catalyzed C(sp2 activation. In this work, we demonstrate that chiral SOHP ligands served as an ideal solution enantioselective amides. Herein, report efficient asymmetric /SOHP-catalyzed β-C(sp3 arylation aliphatic tertiary ligand plays a key role deprotonation-metalation step.

Язык: Английский

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Convergent and Efficient Total Synthesis of (+)-Heilonine Enabled by C–H Functionalizations

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(3), С. 1825 - 1831

Опубликована: Янв. 16, 2024

We report a convergent and efficient total synthesis of the C-nor D-homo steroidal alkaloid (+)-heilonine with hexacyclic ring system, nine stereocenters, trans-hydrindane moiety. Our features four selective C–H functionalizations to form key C–C bonds Stille carbonylative cross-coupling connect AB system DEF Nazarov cyclization construct five-membered C ring. These enabling transformations significantly reduced functional group manipulations delivered in 11 or 13 longest linear sequence (LLS) steps.

Язык: Английский

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Cobalt-Catalyzed Carbon–Heteroatom Transfer Enables Regioselective Tricomponent 1,4-Carboamination

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(12), С. 8508 - 8519

Опубликована: Фев. 21, 2024

Tricomponent cobalt(salen)-catalyzed carbofunctionalization of unsaturated substrates by radical-polar crossover has the potential to streamline access broad classes heteroatom-functionalized synthetic targets, yet reaction platform remained elusive, despite well-developed analogous hydrofunctionalizations mediated high-valent alkylcobalt intermediates. We report herein development a cobalt(salen) catalytic system that enables carbofunctionalization. The entails tricomponent decarboxylative 1,4-carboamination dienes and provides direct route aromatic allylic amines obviating preformed allylation reagents protection oxidation-sensitive amines. merges acridine photocatalysis with regioselective 1,4-carbofunctionalization facilitates radical polar phases coupling process, revealing critical roles reactants, as well ligand effects nature formal species on chemo- regioselectivity.

Язык: Английский

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