Beyond Friedel and Crafts: Directed Alkylation of C−H Bonds in Arenes

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 58(22), P. 7202 - 7236

Published: Aug. 14, 2018

Abstract Alkylation of arenes is one the most fundamental transformations in chemical synthesis and leads to privileged scaffolds many areas science. Classical methods for introduction alkyl groups are mostly based on Friedel–Crafts reaction, radical additions, metalation, or prefunctionalization arene: these methods, however, suffer from limitations scope, efficiency, selectivity. Moreover, they innate reactivity starting arene, favoring alkylation at a certain position rendering chains other positions much more challenging. This can be addressed by use directing group that facilitates, presence metal catalyst, regioselective C−H bond. These directed alkylations bonds will comprehensively summarized this Review.

Language: Английский

---

Ru^II-Catalyzed/NH₂-Assisted Selective Alkenyl C–H [5 + 1] Annulation of Alkenylanilines with Sulfoxonium Ylides to Quinolines

Organic Letters, Journal Year: 2019, Volume and Issue: 21(12), P. 4812 - 4815

Published: June 13, 2019

A novel ruthenium-catalyzed [5 + 1] annulation of 2-alkenylanilines with sulfoxonium ylides was developed for the rapid assembly highly functionalized quinolines. This new catalytic process employs challenging but synthetically ideal free amino functionality to achieve alkenyl C–H activation as one-carbon coupling partners. Various 2-acylquinolines could be obtained good yields and excellent functional group tolerance. Moreover, potential synthetic application this methodology exemplified by several chemical transformations.

Language: Английский

---

Asymmetric transformations from sulfoxonium ylides

Chemical Science, Journal Year: 2021, Volume and Issue: 13(5), P. 1192 - 1209

Published: Dec. 8, 2021

Sulfoxonium ylides are important surrogates for diazo compounds, and their use in industry as safer alternatives has been evaluated during recent years. Beyond the known classical transformations, these have also used a surprising plethora of novel intrinsic chemical reactions, especially Bench stability handling an advantage this class organosulfur molecules. Despite this, efficient asymmetric specifically catalytic enantioselective versions, only recently reported, there specific reasons this. This perspective article covers topic from first studies up to latest advances, giving personal perspectives showing main challenges area coming

Language: Английский

---

Ruthenium(ii)-catalyzed selective C–H bond activation of imidamides and coupling with sulfoxonium ylides: an efficient approach for the synthesis of highly functional 3-ketoindoles

Organic Chemistry Frontiers, Journal Year: 2019, Volume and Issue: 6(8), P. 1183 - 1188

Published: Jan. 1, 2019

Ruthenium-catalyzed selective C–H bond activation of imidamides and annulation sulfoxonium ylides were achieved, which afforded a series 3-ketoindole derivatives in good yields, with functional group compatibility.

Language: Английский

---

Application of sulfoxonium ylide in transition-metal-catalyzed C-H bond activation and functionalization reactions

Tetrahedron, Journal Year: 2021, Volume and Issue: 101, P. 132478 - 132478

Published: Oct. 8, 2021

Language: Английский

---

Co(III), Rh(III) & Ir(III)‐Catalyzed Direct C−H Alkylation/Alkenylation/Arylation with Carbene Precursors

Chemistry - An Asian Journal, Journal Year: 2021, Volume and Issue: 16(5), P. 443 - 459

Published: Jan. 15, 2021

Metal carbenes play a pivotal role in transition-metal-catalyzed synthetic transfer reactions. The metal carbene is generated either from diazo compound through facile extrusion of N2 with catalyst or situ other sources like triazoles, pyriodotriazoles, sulfoxonium ylides and iodonium-ylide. On the hand, Co(III), Rh(III) & Ir(III)-catalyzed C-H functionalizations have been well established as key step to enable construction various transformations. Interestingly, recent years, merging these two concepts activation migratory insertion gained much attention, particular group 9 metal-catalyzed arene precursors via insertion. In this review, we summarize advances direct alkylation/alkenylation/arylation also discuss intermediates within catalytic cycles.

Language: Английский

---

Recent Advances in Metal‐Catalyzed C−H Bond Functionalization Reactions of Sulfoxonium Ylides

Asian Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 11(4)

Published: March 23, 2022

Abstract In recent years, the transition‐metal‐catalyzed functionalization reactions of sulfoxonium ylides have been explored extensively because their usefulness as carbene‐transfer agents, since they can produce metal carbenes through catalysis. Moreover, are safer and advantages simple handling good stability over other counterparts like diazo‐compounds. This review article attempts to highlight advances in metal‐catalyzed C−H ylides.

Language: Английский

---

Sigma-Bond Metathesis as an Unusual Asymmetric Induction Step in Rhodium-Catalyzed Enantiodivergent Synthesis of C–N Axially Chiral Biaryls

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(15), P. 8417 - 8429

Published: March 23, 2023

Mechanistic understanding of asymmetric induction plays a crucial role in designing new catalytic reactions. Reported herein is atroposelective access to C-N axially chiral isoquinolones via rhodium-catalyzed C-H activation N-alkoxy benzamides and annulation with imidoyl sulfoxonium ylides. The coupling system proceeded excellent functional group tolerance, different conditions were identified afford one or the other enantiomeric product each enantioselectivity for representative class ylide reagent, thus making both enantiomers readily available using same catalyst. Experimental computational studies revealed pathway alkylation enantio-determining formal nucleophilic substitution-C-N cyclization that mediated by rhodium catalyst σ-bond metathesis as mechanism. Computational indicated solvent-dependent enatiodivergence originated from levels neutral versus cationic species.

Language: Английский

---

Ruthenium(IV) Intermediates in C−H Activation/Annulation by Weak O‐Coordination

Chemistry - A European Journal, Journal Year: 2018, Volume and Issue: 24(62), P. 16548 - 16552

Published: Sept. 25, 2018

Abstract Ruthenium(IV) complexes were identified as key intermediates of C−H/O−H activations by weak O ‐coordination. Thus, the annulations sulfoxonium ylides benzoic acids provided expedient access to diversely‐decorated isocoumarins with ample scope. Detailed experimental and computational studies strong support for a facile BIES‐C−H activation, along cyclometalated ruthenium(IV) within versatile ruthenium(II/IV) catalysis regime (BIES=base‐assisted internal electrophilic substitution).

Language: Английский

---

Palladium-Catalyzed Oxidative Allylation of Sulfoxonium Ylides: Regioselective Synthesis of Conjugated Dienones

Organic Letters, Journal Year: 2019, Volume and Issue: 21(4), P. 872 - 875

Published: Feb. 6, 2019

The first examples of palladium-catalyzed allylic C–H oxidative allylation sulfoxonium ylides to afford the corresponding conjugated dienones with moderate good yields have been established. features this novel conversion include mild reaction conditions, wide substrate scope, and excellent regioselectivity.

Language: Английский

---