Energy-Transfer-Enabled Regioconvergent Alkylation of Azlactones via Photocatalytic Radical–Radical Coupling DOI
Kun Zhu, Yunhan Ma, Zugen Wu

et al.

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(7), P. 4894 - 4902

Published: March 27, 2023

C-4-selective functionalization of azlactones provides access to α,α-disubstituted unnatural α-amino acids, which has been extensively investigated in the past decades. However, a vast majority such transformations are two-electron transfer reactions. Herein, leveraging on persistent radical effect, we develop photocatalytic energy transfer-enabled regioconvergent alkylation with redox-active esters via radical–radical couplings. This strategy is extended utilization simple alkanes as precursors, whereby aryl play dual role an oxidant and hydrogen-atom-transfer agent. Notably, excited state Ir(III) photocatalyst enables selective activation unwanted imine products through triplet transfer, delivering C-4-functionalized high regioselectivity. Both experimental investigations density functional theory calculations reaction mechanism were performed, supporting EnT-enabled coupling pathways.

Language: Английский

Energy transfer photocatalysis: exciting modes of reactivity DOI
Subhabrata Dutta, Johannes E. Erchinger, Felix Strieth‐Kalthoff

et al.

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(3), P. 1068 - 1089

Published: Jan. 1, 2024

Leveraging light energy to expose the ‘dark’ reactive states describes whole essence of triplet–triplet transfer. This offers an impressive opportunity conduct a multitude diverse reactions and access sought-after molecular motifs.

Language: Английский

Citations

135
EnT-Mediated N–S Bond Homolysis of a Bifunctional Reagent Leading to Aliphatic Sulfonyl Fluorides DOI
Johannes E. Erchinger,

Reece Hoogesteger,

Ranjini Laskar

et al.

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(4), P. 2364 - 2374

Published: Jan. 18, 2023

Sulfur(VI) fluoride exchange (SuFEx) gives rise to a plethora of high-valent sulfur linkages; however, the availability (aliphatic) sulfonyl manifolds lag behind, owing limited sources introducing SO2F moiety via classical two-electron approach. Recently, radical-based methodologies have emerged as complementary strategy increase diversity accessible click partners. In this work, synthesis bench-stable sulfamoyl reagent is presented, which may undergo sigma-bond homolysis upon visible-light-induced sensitization form protected β-amino fluorides from alkene feedstocks. Notably, offers an appealing access various building blocks for peptido fluorides, relevant in medicinal chemistry context, well intriguing entry β-ammonium sulfonates and β-sultams, alkenes. Densely functionalized 1,3-sultones were obtained by employing allyl alcohols substrates. Surprisingly, chloride-derived β-imino underwent S-O bond formation ring closure yield rigid cyclopropyl sulfonate ester under SuFEx conditions. Furthermore, engaging thiol-based hydrogen atom donor reaction, reactivity same can be tuned toward direct aliphatic fluorides. Mechanistic experiments indicate energy transfer (EnT)-mediated process. The transient radical adds product occurs either radical-radical coupling or (HAT), respectively.

Language: Английский

Citations

92
Metal-Free Amino(hetero)arylation and Aminosulfonylation of Alkenes Enabled by Photoinduced Energy Transfer DOI

Xu-Kuan Qi,

Mengjie Zheng, Chao Yang

et al.

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(30), P. 16630 - 16641

Published: July 24, 2023

β-(Hetero)arylethylamines are privileged structural motifs found in many high-value organic molecules, including pharmaceuticals and natural products. To construct these important molecular skeletons, previous methods mainly achieved by amino(hetero)arylation reaction with the aid of transition metals preactivated substrates. Herein, we report a metal-free photoinduced intermolecular for single-step installation both (hetero)aryl iminyl groups across alkenes an efficient regioselective manner. This method shows broad scope (up to 124 examples) excellent tolerance various olefins─from simplest ethylene complex multisubstituted can all participate reaction. Furthermore, aminosulfonylation be also conducted presence sodium bisulfite as SO2 source.

Language: Английский

Citations

59
γ-Amino Alcohols via Energy Transfer Enabled Brook Rearrangement DOI Creative Commons
Ranjini Laskar, Subhabrata Dutta, Jan C. Spies

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(15), P. 10899 - 10907

Published: April 3, 2024

In the long-standing quest to synthesize fundamental building blocks with key functional group motifs, photochemistry in recent past has comprehensively established its attractiveness. Amino alcohols are not only functionally diverse but ubiquitous biologically active realm of compounds. We developed bench-stable bifunctional reagents that could then access sparsely reported γ-amino directly from feedstock alkenes through energy transfer (EnT) photocatalysis. A designed 1,3-linkage across is made possible by intervention a radical Brook rearrangement takes place downstream EnT-mediated homolysis our reagent(s). combination experimental mechanistic investigations and detailed computational studies (DFT) indicates chain propagated reaction pathway.

Language: Английский

Citations

24
Photoredox-Catalyzed Alkene Acylesterification with Acyloxime Esters via C–C and Tertiary C–O Bond Formation DOI

Youkang Zhou,

Ruiying Zhao, Mingyou Hu

et al.

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 7, 2025

We describe an efficient acyl esterification method for alkenes utilizing acyloxime esters as bifunctional reagents featuring radical acylation and congested C–O bond formation. This approach is characterized by mild photoredox conditions, high step atom economy, a broad substrate scope, excellent regioselectivity. A variety of valuable α-acyl hindered alcohol esters, including those obtained via gram-scale synthesis late-stage functionalization pharmaceutical molecules, were presented, demonstrating its synthetic potential practicability.

Language: Английский

Citations

3
Highly Selective Radical Relay 1,4-Oxyimination of Two Electronically Differentiated Olefins DOI
Guangying Tan, Fritz Paulus, Ángel Rentería‐Gómez

et al.

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(47), P. 21664 - 21673

Published: Nov. 16, 2022

Radical addition reactions of olefins have emerged as an attractive tool for the rapid assembly complex structures, and plentiful applications in organic synthesis, however, such are often limited to polymerization or 1,2-difunctionalization. Herein, we disclose unprecedented radical relay 1,4-oxyimination two electronically differentiated with a class bifunctional oxime carbonate reagents via energy transfer strategy. The protocol is highly chemo- regioselective, three different chemical bonds (C-O, C-C, C-N bonds) were formed single operation orchestrated manner. Notably, this reaction provides access large variety structurally diverse products, obtained products could be easily converted into valuable biologically relevant δ-hydroxyl-α-amino acids. With combination experimental theoretical methods, mechanism has been investigated. Theoretical calculations reveal that chain might operate reaction.

Language: Английский

Citations

47
Metal-Free Photoinduced Acylboration of [1.1.1]Propellane via Energy Transfer Catalysis DOI
Saegun Kim, Hyunjung Oh, Weizhe Dong

et al.

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(14), P. 9542 - 9549

Published: July 5, 2023

Highly strained 1,3-disubstituted bicyclo[1.1.1]pentanes (BCPs) have been established as bioisosteres of para-disubstituted benzene because they impart valuable pharmacokinetic properties. Herein, we demonstrate an energy transfer-mediated protocol for acylboration [1.1.1]propellanes that allows the direct construction various carbonyl species, such carbamoyl-, carboxyl-, and acyl-, in tandem with synthetically versatile pinacol boronate (Bpin) groups onto BCP substructure under simple reaction conditions. Moreover, drug-like molecules containing boronates are further submitted to late-stage functionalization events. Several important transformations Bpin functional group boronates, including photoinduced cross-coupling reactions BCP-BF3K, derived from BCP-Bpin, were successfully performed showcase synthetic utility. Additionally, diverse elaborate mechanistic investigations provide insights, a plausible mechanism is proposed.

Language: Английский

Citations

40
Metal-free photosensitized radical relay 1,4-carboimination across two distinct olefins DOI Creative Commons
Guangying Tan, Fritz Paulus, Alessia Petti

et al.

Chemical Science, Journal Year: 2023, Volume and Issue: 14(9), P. 2447 - 2454

Published: Jan. 1, 2023

Intermolecular carboamination of olefins offers a powerful platform for the rapid construction structurally complex amines from abundant feedstocks. However, these reactions often require transition-metal catalysis, and are mainly limited to 1,2-carboamination. Herein, we report novel radical relay 1,4-carboimination across two distinct with alkyl carboxylic acid-derived bifunctional oxime esters

Language: Английский

Citations

31
1,2‐Difunctionalization of Acetylene Enabled by Light DOI

Shiwei Lü,

Zipeng Wang, Xiang Gao

et al.

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(16)

Published: Feb. 27, 2023

Although the direct conversion of gaseous acetylene into value-added liquid commodity chemicals is becoming increasingly attractive, majority established methodologies are focused on cross-coupling, hydro-functionalization, and polymerization. Herein, we describe a 1,2-difunctionalization method that inserts directly readily available bifunctional reagents. This provides access to diverse C2-linked 1,2-bis-heteroatom products in high regio- stereoselectivity along with opening up previously unexplored synthetic directions. In addition, demonstrate this method's potential by converting obtained functionalized molecules chiral sulfoxide-containing bidentate ligands. Using combination experimental theoretical methods, mechanism for insertion reaction was investigated.

Language: Английский

Citations

30
Photosensitized Vicinal Sulfonylamination of Alkenes with Oxime Ester and DABCO·(SO2)2 DOI

Chu‐Ping Yuan,

Yu Zheng, Zhenzhen Xie

et al.

Organic Letters, Journal Year: 2023, Volume and Issue: 25(10), P. 1782 - 1786

Published: March 8, 2023

A metal-free photosensitized three-component reaction of oxime esters, alkenes, and DABCO·(SO2)2 was developed. This protocol could accommodate a wide substrate scope, including activated unactivated alkenes aryl aliphatic carboxylic acid delivering broad range β-amino sulfones in moderate to high yields. The insertion SO2 as linker moiety allows the manipulation functionality process, expanding utility esters bifunctional reagents.

Language: Английский

Citations

28