Thioethers as Dichotomous Electrophiles for Site‐Selective Silylation via C−S Bond Cleavage DOI
Shuai Chen, Xueying Guo,

Haoran Hou

et al.

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(25)

Published: April 18, 2023

The development of aryl alkyl sulfides as dichotomous electrophiles for site-selective silylation via C-S bond cleavage has been achieved. Iron-catalyzed selective C(aryl)-S bonds can occur in the presence β-diketimine ligands, and C(alkyl)-S be achieved by t-BuONa without use transition metals, resulting corresponding silylated products moderate to excellent yields. Mechanistic studies suggest that Fe-Si species may undergo metathesis reactions during bonds, while silyl radicals are involved bonds.

Language: Английский

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

et al.

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(19), P. 11984 - 11999

Published: Sept. 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.

Language: Английский

Citations

203
Radical Reactions with N-Heterocyclic Carbene (NHC)-Derived Acyl Azoliums for Access to Multifunctionalized Ketones DOI

Hui Cai,

Xiaoqun Yang,

Shi‐Chao Ren

et al.

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(11), P. 8270 - 8293

Published: May 13, 2024

As one of the most important key intermediates, NHC-bound acylazolium-based ionic transformations have been intensively explored in past two decades. With expeditious development NHC-catalyzed radical recent years, acylazolium chemistry has reached another level, with number relevant publications increasing significantly. However, a summary focused on acylations NHC-derived acyl azoliums classified according to mechanistic difference not reported. Such detailed classification and deep analysis provide opportunities for better understanding history trend this field. In review, reactions N-heterocyclic carbene (NHC)-derived are systematically introduced. The achievements challenges within area also summarized discussed at end.

Language: Английский

Citations

23
Recent advances in photo- and electro-enabled radical silylation DOI
Liqing Ren, Na Li, Jie Ke

et al.

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(22), P. 6400 - 6415

Published: Jan. 1, 2022

This review aims to highlight the recent advances in area of radical type silylation reactions mediated by photo- and electrocatalysis.

Language: Английский

Citations

62
Photoinduced Electron Transfer from Xanthates to Acyl Azoliums: Divergent Ketone Synthesis via N‐Heterocyclic Carbene Catalysis DOI
Chang‐Yin Tan, Minseok Kim, Sungwoo Hong

et al.

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(32)

Published: June 12, 2023

Considering the prevalence of alcohols and carboxylic acids, their fragment cross-coupling reactions could hold significant implications in organic synthesis. Herein, we report a versatile method for synthesizing diverse range ketones from acid derivatives via N-heterocyclic carbene (NHC) catalysis. Mechanistic investigations revealed that photoexcited xanthates acyl azoliums undergo single electron transfer (SET) under photocatalyst-free conditions, generating NHC-derived ketyl radicals alkyl radicals. These open-shell intermediates subsequently radical-radical reaction, yielding valuable ketones. Furthermore, this approach can be employed three-component involving alkenes enynes, resulting structurally cross-coupled The unified strategy offers unique opportunity coupling derivatives, accommodating functional groups even complex settings.

Language: Английский

Citations

33
Iminoacylation of Alkenes via Photoredox N-Heterocyclic Carbene Catalysis DOI

Yi-Xiong Dong,

Chun-Lin Zhang, Zhong‐Hua Gao

et al.

Organic Letters, Journal Year: 2023, Volume and Issue: 25(5), P. 855 - 860

Published: Jan. 26, 2023

The iminoacylation of alkenes via photoredox N-heterocyclic carbene catalysis is developed with the employment alkene-tethered α-imino-oxy acids and acyl imidazoles. corresponding substituted 3,4-dihydro-2H-pyrroles were afforded in moderate to good yields high diastereoselectivities most cases. reaction involves 5-exo-trig radical cyclization an iminyl following coupling a ketyl from imidazole under NHC catalysis.

Language: Английский

Citations

31
Recent advances in three-component radical acylative difunctionalization of unsaturated carbon–carbon bonds DOI
Jiaqiong Sun, Lihong V. Wang, Guangfan Zheng

et al.

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(18), P. 4488 - 4515

Published: Jan. 1, 2023

This review highlights the recent advances in radical acylated difunctionalization of unsaturated carbon–carbon bonds and focuses on mechanistic insights these transformations.

Language: Английский

Citations

31
Silyl Radical Generation from Silylboronic Pinacol Esters through Substitution with Aminyl Radicals DOI

Hongyan Lan,

Xiangyu Huo,

Ying‐Gang Jia

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(5), P. 1011 - 1016

Published: Jan. 30, 2024

A novel strategy was developed to generate silyl radicals from silylboronic pinacol esters (SPEs) through nucleohomolytic substitution of boron with aminyl radicals. We successfully applied this obtain diverse organosilicon compounds using SPEs and N-nitrosamines under photoirradiation without any catalyst. The ability access offers a new perspective for chemists rapidly construct Si–X bonds.

Language: Английский

Citations

11
Silylarylation of Alkenes via meta-Selective C–H Activation of Arenes under Ruthenium/Iron Cooperative Catalysis: Mechanistic Insights from Combined Experimental and Computational Studies DOI

Sukanya Neogi,

Sourav Bhunya,

Asim Kumar Ghosh

et al.

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(7), P. 4510 - 4522

Published: March 12, 2024

Organosilicons are privileged skeletons in the domains of pharmaceutical chemistry, organic synthesis, and materials science. Hence, investigating catalytic techniques for synthesis organosilicon compounds has received a great deal emphasis. Carbosilylation alkenes is an efficient technique to introduce diverse molecular architectures containing silicon into chemical space. However, organohalides pseudohalides prerequisites most existing carbosilylation protocols. On other hand, utilization C–H activation been sowing seeds successful development intricate scaffolds. In this regard, synthetic accessibility complexed derivatives by through meta-C–H approach remained intangible. Herein, we present three-component strategy arylsilylation olefins with (het)arenes silanes integrating iron-catalyzed silyl radical generation, coupled intrinsic reactivity alkene, ruthenium-catalyzed functionalization (het)arene, leading targeted cross-coupled carbosilylated product. addition, theoretical investigations state-of-the-art dispersion corrected density functional theory at B3PW91-D3/Def2TZVP/CPCM(PhCF3) shed intriguing insights on selectivity probable mechanistic pathway underexplored cooperative 3d/4d transition metal catalysis, such as formation its addition alkene catalyzed iron, followed meta-selective ruthenium bound arene, furnishing C4 substituted (het)arene functionalized compounds.

Language: Английский

Citations

10
Photocatalyzed regioselective hydrosilylation for the divergent synthesis of geminal and vicinal borosilanes DOI Creative Commons

Degong Kong,

Muliang Zhang, Yuchao Zhang

et al.

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: May 2, 2023

Geminal and vicinal borosilanes are useful building blocks in synthetic chemistry material science. Hydrosilylation/hydroborylation of unsaturated systems offer expedient access to these motifs. In contrast the well-established transition-metal-catalyzed methods, radical approaches rarely explored. Herein we report synthesis geminal from α-selective hydrosilylation alkenyl boronates via photoinduced hydrogen atom transfer (HAT) catalysis. Mechanistic studies implicate that α-selectivity originates a kinetically favored addition an energetically HAT process. We further demonstrate selective through allyl 1,2-boron migration. These strategies exhibit broad scopes across primary, secondary, tertiary silanes various boron compounds. The utility is evidenced by multi-borosilanes diverse fashion scaling up continuous-flow synthesis.

Language: Английский

Citations

21
Radical acylation: concepts, synthetic applications and directions DOI
Yue Zhang, Yili Zhang, Jian Lin

et al.

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(4), P. 1056 - 1085

Published: Jan. 1, 2023

In this tutorial, reaction scopes, limitations and mechanisms of radical acylations are summarized discussed according to types catalytic systems.

Language: Английский

Citations

20