Stereoselective benzylic C(sp³)–H alkenylation enabled by metallaphotoredox catalysis

Chemical Science, Journal Year: 2024, Volume and Issue: 15(31), P. 12511 - 12516

Published: Jan. 1, 2024

We report a site- and stereoselective benzylic C(sp 3 )–H alkenylation utilizing metallaphotoredox catalysis. In addition, enantioselective can successfully produce highly enantioenriched tetrasubstituted olefins.

Language: Английский

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Selective Functionalization of Alkenes and Alkynes by Dinuclear Manganese Catalysts

Accounts of Chemical Research, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 2, 2024

ConspectusAlkenes and alkynes are fundamental building blocks in organic synthesis due to their commercial availability, bench-stability, easy preparation. Selective functionalization of alkenes is a crucial step for the value-added compounds. Precise control over these reactions allows efficient construction complex molecules with new functionalities. In recent decades, second- third-row precious transition metal catalysts (palladium, platinum, rhodium, ruthenium) have been pivotal development metal-catalyzed synthetic methodology. These metals exhibit excellent catalytic activity selectivity, enabling functionalized molecules. However, recovery reuse long challenge this field. years, exploration earth-abundant has interested both academic industrial researchers. The such systems offers promising approach overcome limitations catalysts. For example, manganese third most naturally abundant minimal toxicity biocompatibility. It exhibits good several reactions, including C-H bond functionalization, selective reduction, radical reactions. This Account outlines our progress dinuclear catalysis alkynes. We established elementary manganese(I)-catalysis transmetalation R-B(OH)

Language: Английский

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Biomimetic Dehydrogenative Intermolecular Formal Allylic Amidation of Branched α‐Olefins

Advanced Science, Journal Year: 2024, Volume and Issue: 12(2)

Published: Nov. 18, 2024

Abstract Allylic amide moieties are commonly encountered in natural products and privileged structures pharmaceuticals agrochemicals. Moreover, because allylic can be to converted into an array of high‐value motifs, they have been widely employed organic synthesis. However, the development catalytic systems for intermolecular amidation olefins, particularly branched α ‐olefins, has proven challenging. Here, a biomimetic, synergistic method is reported that combines photoredox, cobalt, Brønsted base catalysis synthesis substituted amides from ‐olefins simple imides without using oxidants. This low‐cost, operationally features broad substrate scope excellent functional group compatibility. it successfully used functionalization several structurally complex molecules demonstrating method's potential utility medicinal chemistry applications. Mechanistic studies revealed C( sp 3 )─N bond formation mediated by nitrogen‐centered radical intermediate, which generated via sequence involving deprotonation single‐electron oxidation.

Language: Английский

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Tailoring the Coordination Environment of Cu Single Atoms for Achieving Regioselective C–C Bond Activation of Amides

ACS Catalysis, Journal Year: 2024, Volume and Issue: unknown, P. 18408 - 18418

Published: Dec. 2, 2024

C–C bond activation can provide a direct reconstruction strategy of carbon skeletons to furnish number structurally diverse molecules. In general, regioselectivity represents the state-of-the-art owing existence several different carbon–carbon bonds, having high BDE, ∼90 kcal/mol. Here, we report directed for amides concise synthesis range urea derivatives and carbamates via regioselective enabled by heterogeneous single-atom copper catalyst (Cu-SAC), with turnover frequency 249 h–1, which is 19 times higher than that analogous homogeneous catalyst. Multitechnique characterization data show Cu species are associated an unsaturated coordination structure plentiful oxygen vacancies on γ-Al2O3 facilitate adsorption multiple coordinated dioxygen, leading catalytic activity selectivity. It would offer opportunities speed up heterogenized process catalysts in inert-bond reactions.

Language: Английский

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White-Light initiated Mn2(CO)10/HFIP-Catalyzed anti-Markovnikov hydrosilylation of alkenes

Journal of Catalysis, Journal Year: 2023, Volume and Issue: 429, P. 115269 - 115269

Published: Dec. 22, 2023

Language: Английский

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Blue‐Light Irradiated Mn(0)‐Catalyzed Hydroxylation and C(sp³)−H Functionalization of Unactivated Alkanes with C(sp²)−H Bonds of Quinones for Alkylated Hydroxy Quinones and Parvaquone

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 30(12)

Published: Nov. 23, 2023

Abstract Site‐selective C( sp 3 )−H functionalization of unreactive hydrocarbons is always challenging due to its inherited chemical inertness, slightly different reactivity various C−H bonds, and intrinsically high bond dissociation energies. Here, a site‐selective alkylation naphthoquinone with unactivated using Mn 2 (CO) 10 as catalyst under blue‐light (457 nm) irradiation without any external acid or base pre‐functionalization presented. The selective tertiary over secondary primary bonds in abundant feedstocks was achieved, hydroxylation quinones realized situ by employing the developed methodology. This protocol provides new catalytic system for direct construction high‐value‐added compounds, namely, parvaquone (a commercially available drug used treat theileriosis ) derivatives ambient reaction conditions. Moreover, this operationally simple applies linear‐, branched‐, cyclo‐alkanes degrees site selectivity irradiated conditions could provide rapid straightforward access versatile methodologies upgrading feedstock chemicals. Mechanistic insight radical trapping, scavenging, EPR, other controlled experiments well corroborated DFT studies suggest that proceeds pathway.

Language: Английский

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Cobalt‐Catalyzed Allylic Alkylation at sp3‐Carbon Centers

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(47)

Published: June 13, 2024

Abstract The rising demand and financial costs of noble transition metal catalysts have emphasized the need for sustainable catalytic approaches. Over past few years, base‐metal emerged as ideal candidates to replace their noble‐metal counterparts because abundance easiness handling. Despite significant advancements achieved with precious metals, earth‐abundant cobalt efficient alternatives allylic substitution reactions. In this review, alkylations at sp 3 ‐carbon centers mediated by will be discussed, a special focus on mechanistic features, scope, limitations.

Language: Английский

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Near-Infrared-Light-Induced Iron(I) Dimer-Enabled Radical Cascade Reactions of Fluoroalkyl Bromides for the Synthesis of Ring-Fused Quinazolinones

Organic Letters, Journal Year: 2024, Volume and Issue: 26(37), P. 7976 - 7980

Published: Sept. 6, 2024

The use of an earth-abundant and inexpensive iron complex as a catalyst, coupled with near-infrared (NIR) light the energy source, for radical reactions alkyl halides has been far less developed. In this study, we report NIR light-mediated iron(I) dimer-catalyzed cascade fluoroalkyl bromides synthesis ring-fused quinazolinones bearing difluoromethyl group. process, 3-bromo-1,10-phenanthroline ligand facilitates reactivity [CpFe(CO)

Language: Английский

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Construction of indolizine scaffolds from α,ω-alkynoic acids and α,ω-vinylamines via sequential-relay catalysis in “one pot”

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(12), P. 2474 - 2479

Published: Jan. 1, 2024

A simple and efficient method for the synthesis of indolizin-3-ones through sequential Au( i )-catalyzed hydrocarboxylation, aminolysis, cyclization, followed by ruthenium-catalyzed ring-closing metathesis.

Language: Английский

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Manganese(I)‐Catalyzed Enantioselective C(sp²)−C(sp³) Bond‐Forming for the Synthesis of Skipped Dienes with Synergistic Aminocatalysis

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(19)

Published: March 16, 2024

Abstract Mn(I)‐catalyzed enantioselective C−C bond‐forming reactions represent a great challenge in homogeneous catalysis primarily due to limited understanding of its mechanistic principles. Herein, we have developed an interesting catalytic strategy that leverages synergistic combination dimeric manganese(I) catalyst and chiral aminocatalyst address this issue. A range conjugated dienals trienals can exclusively proceed 1,4‐hydroalkenylation by using readily available aromatic aliphatic alkenyl boronic acids as coupling partners, producing rich library skipped diene aldehydes synthetically useful yields high levels enantioselectivities. Notably, downstream transformations these products not only afford concise approach construct enantioenriched trienes but also realize total synthesis analogues (−)‐Blepharocalyxin D four steps. DFT calculations suggest the is kinetically more favorable than 1,6‐hydroalkenylation.

Language: Английский

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