Remote C(sp3)−H Acylation of Amides and Cascade Cyclization via N‐Heterocyclic Carbene Organocatalysis DOI
Qing‐Zhu Li, Rong Zeng, Fan Yang

и другие.

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(15)

Опубликована: Фев. 3, 2022

Abstract The direct functionalization of inert C(sp 3 )−H bonds under environmentally benign catalytic conditions remains a challenging task in synthetic chemistry. Here, we report an organocatalytic remote acylation amides and cascade cyclization through radical‐mediated 1,5‐hydrogen atom transfer mechanism using N‐heterocyclic carbene as the catalyst. Notably, diversity nitrogen‐containing substrates, including simple linear aliphatic carbamates ortho ‐alkyl benzamides, can be successfully applied to this system. With established protocol, over 120 examples functionalized δ‐amino ketones isoquinolinones with diverse substituents were easily synthesized up 99 % yield mild conditions. robustness generality strategy further highlighted by successful unactivated late‐stage modification pharmaceutical molecules. Then, asymmetric control radical reaction was attempted proven feasible newly designed chiral thiazolium catalyst, moderate enantioselectivity obtained at current stage. Preliminary mechanistic investigations several reactions, KIE experiments, computational studies shed light on mechanism.

Язык: Английский

Recent advances in the chemistry and applications of N-heterocyclic carbenes DOI
Peter Bellotti, Maximilian Koy, Matthew N. Hopkinson

и другие.

Nature Reviews Chemistry, Год журнала: 2021, Номер 5(10), С. 711 - 725

Опубликована: Сен. 3, 2021

Язык: Английский

Процитировано

474
Cooperative NHC and Photoredox Catalysis for the Synthesis of β‐Trifluoromethylated Alkyl Aryl Ketones DOI Creative Commons
Qingyuan Meng,

Nadine Döben,

Armido Studer

и другие.

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(45), С. 19956 - 19960

Опубликована: Июль 23, 2020

Despite the great potential of radical chemistry in organic synthesis, N-heterocyclic carbene (NHC)-catalyzed reactions involving intermediates are not well explored. This communication reports three-component coupling aroyl fluorides, styrenes and Langlois reagent (CF3 SO2 Na) to give various β-trifluoromethylated alkyl aryl ketones with good functional group tolerance moderate high yields by cooperative photoredox/NHC catalysis. The alkene acyltrifluoromethylation proceeds via radical/radical cross ketyl radicals benzylic C-radicals. generated SET reduction situ formed acylazolium ions whereas derive from trifluoromethyl addition onto styrenes.

Язык: Английский

Процитировано

202
Radical NHC Catalysis DOI
Kun Liu, Max Schwenzer, Armido Studer

и другие.

ACS Catalysis, Год журнала: 2022, Номер 12(19), С. 11984 - 11999

Опубликована: Сен. 19, 2022

Radical/radical cross-coupling reactions represent an efficient and straightforward approach for the construction of chemical bonds accordingly have drawn increasing attention over past decades. In order to achieve synthetically useful transformations, a persistent radical should be coupled with transient in accordance effect (PRE). However, known radicals outnumber by far types free radicals, which limits widespread application PRE, until today. Thus, development between has been focus, meanwhile transition-metal catalysis successfully implemented artificially prolong lifetimes, allowing their utilization formal radical/radical cross-couplings. Complementary research field recently uncovered that organocatalytically generated NHC-derived ketyl are type catalytically radicals. NHC-catalyzed transformations aldehydes carboxylic acid derivatives enabled disclosure ever-increasing number interesting reactions, different from traditional ionic processes, offering otherwise inaccessible activation modes. These discoveries opened door NHC organocatalysis manipulation reactions. Due its obvious potential synthetic organic chemistry, it is timely provide perspective on this emerging field.

Язык: Английский

Процитировано

202
Benzylic C−H acylation by cooperative NHC and photoredox catalysis DOI Creative Commons
Qingyuan Meng, Lena Lezius, Armido Studer

и другие.

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Апрель 6, 2021

Methods that enable site selective acylation of sp

Язык: Английский

Процитировано

154
Direct α-Acylation of Alkenes via N-Heterocyclic Carbene, Sulfinate, and Photoredox Cooperative Triple Catalysis DOI
Kun Liu, Armido Studer

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(13), С. 4903 - 4909

Опубликована: Март 24, 2021

N-Heterocyclic carbene (NHC) catalysis has emerged as a versatile tool in modern synthetic chemistry. Further increasing the complexity, several processes have been introduced that proceed via dual catalysis, where NHC organocatalyst operates concert with second catalytic moiety, significantly enlarging reaction scope. In biological transformations, multiple is generally used to access complex natural products. Guided by strategy, triple studied recently, three different modes are merged single process. this Communication, direct α-C–H acylation of various alkenes aroyl fluorides using NHC, sulfinate, and photoredox cooperative reported. The method allows preparation α-substituted vinyl ketones moderate high yields excellent functional group tolerance. Mechanistic studies reveal these cascades through sequential radical addition/coupling/elimination contrast known operate two sets interwoven cycles, process, all cycles interwoven.

Язык: Английский

Процитировано

151
Aryl radical-mediated N-heterocyclic carbene catalysis DOI Creative Commons

Yuki Matsuki,

Nagisa Ohnishi,

Yuki Kakeno

и другие.

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Июнь 22, 2021

Abstract There have been significant advancements in radical reactions using organocatalysts modern organic synthesis. Recently, NHC-catalyzed initiated by single electron transfer processes actively studied. However, the reported examples limited to catalysis mediated alkyl radicals. In this article, NHC organocatalysis aryl radicals has achieved. The enolate form of Breslow intermediate derived from an aldehyde and thiazolium-type presence a base undergoes iodide, providing radical. catalytically generated could be exploited as arylating reagent for relay-type arylacylation styrenes hydrogen atom abstraction α-amino C(sp 3 )–H acylation secondary amides.

Язык: Английский

Процитировано

142
Aroyl Fluorides as Bifunctional Reagents for Dearomatizing Fluoroaroylation of Benzofurans DOI Creative Commons
Xiaoye Yu, Qingyuan Meng, Constantin G. Daniliuc

и другие.

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(16), С. 7072 - 7079

Опубликована: Март 22, 2022

The 2,3-dihydrobenzofuran scaffold is widely found in natural products and biologically active compounds. Herein, dearomatizing 2,3-fluoroaroylation of benzofurans with aroyl fluorides as bifunctional reagents to access 2,3-difunctionalized dihydrobenzofurans reported. reaction that occurs by cooperative NHC/photoredox catalysis provides 3-aroyl-2-fluoro-2,3-dihydrobenzofurans moderate good yield high diastereoselectivity. Cascades proceed via radical/radical cross-coupling a benzofuran radical cation generated the photoredox cycle neutral ketyl formed through NHC cycle. redox-neutral transformation exhibits broad substrate scope functional group compatibility. With anhydrides reagents, aroyloxyacylation achieved strategy can also be applied

Язык: Английский

Процитировано

122
Cooperative NHC/Photoredox Catalyzed Ring‐Opening of Aryl Cyclopropanes to 1‐Aroyloxylated‐3‐Acylated Alkanes DOI
Zhijun Zuo, Constantin G. Daniliuc, Armido Studer

и другие.

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(48), С. 25252 - 25257

Опубликована: Сен. 28, 2021

Cyclopropanes are an important class of building blocks in organic synthesis. Herein, a ring-opening/arylcarboxylation/acylation cascade reaction for the 1,3-difunctionalization aryl cyclopropanes enabled by cooperative NHC and organophotoredox catalysis is reported. The works on monosubstituted that contrast to heavily investigated donor-acceptor more challenging be difunctionalized. key step radical/radical cross coupling benzylic radical generated photoredox cycle with ketyl from cycle. transformation features metal-free conditions tolerates diverse range functionalities.

Язык: Английский

Процитировано

115
Single-electron carbene catalysis in redox processes DOI
Anna V. Bay, Karl A. Scheidt

Trends in Chemistry, Год журнала: 2022, Номер 4(4), С. 277 - 290

Опубликована: Фев. 11, 2022

Язык: Английский

Процитировано

98
Carbene and photocatalyst-catalyzed decarboxylative radical coupling of carboxylic acids and acyl imidazoles to form ketones DOI Creative Commons
Shi‐Chao Ren, Xing Yang, Bivas Mondal

и другие.

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Май 23, 2022

The carbene and photocatalyst co-catalyzed radical coupling of acyl electrophile a precursor is emerging as attractive method for ketone synthesis. However, previous reports mainly limited to prefunctionalized precursors two-component coupling. Herein, an N-heterocyclic catalyzed decarboxylative carboxylic acids imidazoles disclosed, in which the are directly used precursors. could also be generated situ by reaction acid with CDI thus furnishing formally two acids. In addition, successfully extended three-component using alkene third partner via relay process. mild conditions, operational simplicity, use reacting partners make our powerful strategy construction complex ketones from readily available starting materials, late-stage modification natural products medicines.

Язык: Английский

Процитировано

84