A Rare Earth Metal Catalyzed Aerobic Dehydrogenation of N-Heterocycles DOI
Ting Zhang,

Yongheng Lv,

Zhenguo Zhang

et al.

Organic Letters, Journal Year: 2023, Volume and Issue: 25(24), P. 4468 - 4472

Published: June 9, 2023

Rare earth metals exhibit high catalytic activity and selectivity in various organic reactions due to their unique electronic properties. Among them, praseodymium has shown under mild reaction conditions compared with transitional metals. Here, we report a strategy of Pr-catalyzed aerobic dehydrogenative aromatization saturated N-heterocycles produce 7 classes products broad substrate scope.

Language: Английский

Red-Light Mediated Formylation of Indoles Using Helical Carbenium Ion as Photoredox Catalyst DOI

Nand Lal,

Deepshikha Deepshikha,

P. R. SINGH

et al.

Chemical Communications, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

A red-light ( λ = 640 nm)-mediated C-3 formylation of indoles utilizing a helical carbenium ion as photocatalyst and 2,2-dimethoxy- N , -dimethylethanamine formylating source is presented.

Language: Английский

Citations

1
Transition‐Metal‐Catalyzed C−H Bond Functionalization of Arenes/Heteroarenes via Tandem C−H Activation and Subsequent Carbene Migratory Insertion Strategy DOI
Neha Jha, Nandkishor Prakash Khot, Manmohan Kapur

et al.

The Chemical Record, Journal Year: 2021, Volume and Issue: 21(12), P. 4088 - 4122

Published: Oct. 14, 2021

Abstract The past decade has witnessed tremendous developments in transition‐metal‐catalyzed C−H bond activation and subsequent carbene migratory insertion reactions, thus assisting the construction of diverse arene/heteroarene scaffolds. Various transition‐metal catalysts serve this purpose provide efficient pathways for an easy access to substituted heterocycles. A brief introduction metal‐carbenes been provided along with key mechanistic underlying coupling reactions. review is a concise knowledge about directing group‐assisted varied arenes/heteroarenes acceptor‐acceptor/donor‐acceptor diazo compounds. also highlights synthesis various carbocycles fused heterocycles through pathways, via C−C, C−N C−O forming mechanism usually involves process, followed by leading coupling.

Language: Английский

Citations

45
Ynones in dearomative spirocyclisation processes; a review DOI Creative Commons
Richard J. K. Taylor, William P. Unsworth

Tetrahedron Chem, Journal Year: 2024, Volume and Issue: 9, P. 100055 - 100055

Published: Jan. 14, 2024

This review concentrates on our research into the discovery of novel ynone-based dearomative spirocyclisation processes, whilst placing new chemistry context existing knowledge. The genesis programme, development efficient synthetic routes to prepare natural products spirobacillene A (1) and B (2), utilised indole ynones. stimulated a much wider study explore reactivity ynones in processes more generally. Routes generate wide range spirocycles were subsequently developed, with reactions tethered indoles, benzofurans, benzisoxazoles, pyrroles, pyridines, isoquinolines, pyrazines, cyclic ketimines, anisoles all discussed herein, these initiated by catalytic Ag(I), Cu(II), Pd(0), photolysis many other reagents. Asymmetric variants some are also discussed, as is further elaboration spirocyclic give carbazoles, quinolones, polycycles useful building blocks. Finally, applications methodology product synthesis (e.g. A, lasubine II indolizidine 209D) described.

Language: Английский

Citations

7
Iodine-mediated oxidative triple functionalization of indolines with azoles and diazonium salts DOI
Yifeng Liu,

Xiaoting Gu,

Xiaoxiang Zhang

et al.

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(34), P. 4613 - 4616

Published: Jan. 1, 2024

We report an innovative synthetic strategy for the generation of polysubstituted indoles from indolines, aryldiazonium salts, and azoles. The methodology encompasses electrophilic substitution reaction affording C5-indoline intermediates which undergo iodine-mediated oxidative transformation coupled with C-H functionalization to yield indole derivatives.

Language: Английский

Citations

6
Recent Progress in Gold‐Catalyzed Reactions of Alkynes for the Construction of Indole Frameworks DOI
Suven Das

Asian Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 12(8)

Published: June 21, 2023

Abstract Indole heterocycles hold an important position in chemical landscape because of their prominence natural products and pharmaceuticals. Consequently, development new efficient strategies to access indole scaffold are continuous interest. For the past few years, gold‐catalyzed activation alkyne has emerged as a powerful strategy for constructing heterocyclic skeleton. The present review highlights recent advances (2018–2023) toward synthesis skeletons via annulations alkynes. A variety alkynes, such as, ynamides, azido ortho ‐alkynyl anilines, propargylic alcohols, phenylimines, miscellaneous alkynes employed affording various architectures under gold catalysis. Moreover, mechanisms included most cases better understanding reaction pathway.

Language: Английский

Citations

15
Weak‐Chelation Assisted Regioselective Indole C(4)‐Alkynylation via Six‐Membered Cobaltacycle Intermediate DOI

Sofaya Joshi,

Riya Dutta, Shyam Kumar Banjare

et al.

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(6), P. 1341 - 1347

Published: Jan. 13, 2024

Abstract Herein a regioselective indole C4‐alkynylation has been uncovered utilizing an earth‐abundant cobalt(III)‐catalyst. For this process, (bromoethynyl)benzene was used as alkynylating agent. Also, after screening various amide‐protected chelating groups we found dimethyl‐amide is optimal for the in‐situ generation of cobaltacycle intermediate. The six‐membered intermediate detected through high‐resolution mass spectrometry HRMS, which key conversion. Further, mechanistic studies were performed such KIE experiments, and reactions with radical scavengers, based on results plausible mechanism proposed. Moreover, to show application methodology, product oxidized diketone, monoketone, alkene, alkane further derivatized tricycle derivative, core structure many natural products.

Language: Английский

Citations

5
Tunable C–H functionalization and dearomatization enabled by an organic photocatalyst DOI Creative Commons

Bohang An,

Hao Cui, Chao Zheng

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: 15(11), P. 4114 - 4120

Published: Jan. 1, 2024

Starting from the same substrates, tunable C–H functionalization and dearomatization have been achieved under catalysis of a new organic photocatalyst – isoazatruxene ITN-2.

Language: Английский

Citations

5
Three-component dicarbofunctionalization of allylamines via nucleopalladation pathway: unlocking vicinal and geminal selectivity DOI Creative Commons

Nityananda Ballav,

Shib Nath Saha,

Shailesh Yadav

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: 15(13), P. 4890 - 4896

Published: Jan. 1, 2024

A palladium( ii )-catalyzed vicinal and geminal selective dicarbofunctionalization of allylamine embedded in a removable picolinamide auxiliary is developed by exploiting nucleopalladation-triggered intermolecular three-component coupling reaction.

Language: Английский

Citations

5
Pd(II)-Catalyzed Transient Directing Group-Assisted Regioselective Diverse C4–H Functionalizations of Indoles DOI
Anurag Singh, Arnab Dey, Kuntal Pal

et al.

Organic Letters, Journal Year: 2022, Volume and Issue: 24(10), P. 1941 - 1946

Published: March 9, 2022

The development of a rational strategy for achieving site-selective C4–H halogenation indoles is an appealing yet challenging task. Herein, we disclose Pd(II)-catalyzed transient directing group (TDG)-assisted methodology realizing C4 chlorination/bromination employing glycine as the TDG and NFSI bystanding oxidant. use inexpensive commercially available CuX2 halide source key highlight this protocol. Furthermore, was also extended to accessing acetoxylated acetic acid acetate 1-fluoro-2,4,6-trimethylpyridinium triflate

Language: Английский

Citations

21
Catalyst-Controlled Chemodivergent Reactivity of Vinyl Cyclopropanes: A Selective Approach toward Indoles and Aniline Derivatives DOI
Santosh Kumar Keshri, Suchithra Madhavan, Manmohan Kapur

et al.

Organic Letters, Journal Year: 2022, Volume and Issue: 24(49), P. 9043 - 9048

Published: Dec. 5, 2022

Herein, we disclose a catalyst-controlled chemodivergent approach to access C2-substituted indoles and diverse aniline derivatives with good chemo- stereoselectivity by employing vinylcyclopropanes (VCPs) as coupling partners via tandem C-H/C-C activation/annulation strategy. The key feature of this work is the divergent reactivity profile showcased VCPs, going beyond allylation under high-valent Rh-/MPAA catalyst system.

Language: Английский

Citations

20