One-pot organocatalyzed synthesis of tricyclic indolizines DOI Creative Commons
Lucas A. Zeoly, Laís V. Acconcia, Manoel T. Rodrigues

et al.

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(17), P. 3567 - 3581

Published: Jan. 1, 2023

Indolizines and their saturated derivatives are important structural motifs present in several biologically active compounds of both natural synthetic origin. We describe herein a one-pot approach for the synthesis tricyclic indolizines catalyzed by bicyclic imidazole-alcohol. The protocol is based on an aqueous Morita-Baylis-Hillman reaction between pyridine-2-carboxaldehydes six- or seven-membered cyclic enones, followed sequential intramolecular cyclization dehydration. So, single operational step two new bonds (C-C C-N) formed organocatalyzed process that takes place simple conditions (stirring water at 60 °C 12 h) with great atom economy (water as sole byproduct), affording purified yields ranging from 19 to 70%. facility strongly depends size cycloalkenone ring: while MBH adducts derived six-, seven- eight-membered cycloenones readily transformed into corresponding indolizines, cyclopentenone-derived do not cyclize. A competition experiment revealed cycloheptenone-derived cyclize faster than cyclohexenone-derived adducts. Model DFT calculations have been performed rationalize these reactivity trends.

Language: Английский

Recent Advances in Electrochemical Cascade Cyclization Reactions DOI
Cai Zhang, Yunyun Liu,

Demao Chen

et al.

Synthesis, Journal Year: 2023, Volume and Issue: 55(18), P. 2911 - 2925

Published: Feb. 20, 2023

Abstract This review highlights recent progress in electrochemical cascade cyclization reactions for the synthesis of carbon rings and heterocycles, such as pyridines, quinolines, phenanthridines, cinnolines, 1,4-dihydroquinolines, oxindoles, imidazo[1,5-α]pyridines, imidazoles, etc. The works included herein are introduced two major sections heterocycle construction carbocycle reactions, covering reported from 2012 to 2022. 1 Introduction 2 Electrochemical Cascade Cyclization Synthesis Heterocycles 2.1 Pyridines, Quinolines, Phenanthridines, Cinnolines 2.2 1,4-Dihydroquinolines, Hexacyclic Sulfonamides, Thiazines 2.3 Hydroisoquinolinones Hydroquinolinones 2.4 Quinazolin-4(3H)-ones 2.5 4H-3,1-Benzoxazines 2.6 Oxindoles 2.7 Indolines Indoles 2.8 Imidazo[1,5-α]pyridines Imidazoles 2.9 Imidazolones, Imidazolidinones, Oxazolones, Oxazolidinones 2.10 Benzoxazoles, Oxazolines, Isoxazolines 2.11 Furans Dihydrofurans 2.12 Indolizines, Pyrazoles, Triazolium Inner Salts 2.13 Sulfonated Benzothiophenes, Thiazoles, Dihydrothiazoles, 1,3,4-Thiadiazoles 2.14 Lactones 3 Construction Carbocycles 3.1 Carbon Polycycles Spiroindenes 3.2 Difluoroacyl (Hetero)arenes Indenones 4 Conclusion

Language: Английский

Citations

23
Base-Promoted Regioselective Annulation of Pyridinium Ylides and Bromoalkynes for the Chemodivergent Synthesis of Indolizines DOI

Xiang Wang,

Huayou Hu,

Qiuyun Li

et al.

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 5, 2025

A base-promoted regioselective formal [3 + 2] annulation of pyridinium ylides with bromoalkynes is reported, producing a series substituent-diverse indolizines in generally good yields. mild K2CO3-promoted three-component cyclization and at 2:1 molar ratio delivered C2-acylmethylated indolizines, whereas C2-brominated were generated starting from bearing strong electron-withdrawing groups the unit by using 2,2,6,6-tetramethyl-1-piperidinyloxy as dehydrogenating reagent. The current synthetic methodology offers controllable modular approach to access different substitution patterns, featuring wide substrate scope, functional group compatibility, complete regioselectivity without demand any transition-metal catalysts.

Language: Английский

Citations

1
B2pin2-Mediated Cascade Cyclization/Aromatization Reaction: Facial Access to Functionalized Indolizines DOI
Xiaoning Li,

Zunsheng Chen,

Weiming Chen

et al.

Organic Letters, Journal Year: 2022, Volume and Issue: 24(40), P. 7372 - 7377

Published: Sept. 29, 2022

Herein, a B2pin2-mediated radical cascade cyclization/aromatization reaction of enaminone with pyridine is described. This strategy provides practical way for the construction valuable functionalized indolizines under metal-, external oxidant-, and base-free conditions, which could be compatible various kinds functional groups, such as halogen, π-system, heterocycle, ferrocenyl, etc. A preliminary mechanism investigation indicated that pyridine-boryl formed in situ triggered to occur.

Language: Английский

Citations

31
Recent Advances in Visible‐Light‐Driven C−S Bond Formation DOI Creative Commons
Jiaxu Feng, Ying Zhang,

XiangDi Wang

et al.

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(20), P. 3413 - 3431

Published: Sept. 12, 2023

Abstract Due their multifaced applications, the access to organosulfur derivatives in an efficient and economical way is a challenge organic synthesis. In this context photochemistry photocatalysis play crucial role development of innovative (and selective) Carbon‐Sulphur bond formation processes. The present review aims collect most recent strategies achieve target under visible light driven conditions.

Language: Английский

Citations

22
Regioselective electrochemical cascade C–H sulfonylation–bromination of indolizines to access difunctionalized indolizines DOI
Wenxuan Jiang, Xiang Liu, Chuanying Zhu

et al.

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(8), P. 2306 - 2312

Published: Jan. 1, 2024

Regioselective electrochemical C–H sulfonylation–bromination between indolizines, sodium sulfinates, and KBr has been established in an undivided cell, which serves as both the brominating agent electrolyte.

Language: Английский

Citations

7
Thermodynamic Controlled Regioselective C1-Functionalization of Indolizines with 3-Hydroxyisoindolinones via Brønsted Acid Catalyzed aza-Friedel–Crafts Reaction DOI
Zhiming Zhu,

Qianling Wu,

Xiaoxiao Song

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(4), P. 2794 - 2799

Published: Jan. 31, 2024

A Brønsted acid catalyzed aza-Friedel–Crafts reaction of indolizines with 3-hydroxyisoindolinones has been established, which constructs isoindolinone derivatives bearing a tetrasubstituted stereocenter in good to high yields and enantioselectivities. Notably, this strategy provides new access C1-functionalization excellent regioselectivities. Moreover, intriguing C1-regioselective transformation was induced under thermodynamic control.

Language: Английский

Citations

6
Synthesis of Indolizines via Tf2O-Mediated Cascade Reaction of Pyridyl-enaminones with Thiophenols/Thioalcohols DOI
Changyuan Zhang, Wei Wang,

Xuncheng Zhu

et al.

Organic Letters, Journal Year: 2023, Volume and Issue: 25(7), P. 1192 - 1197

Published: Feb. 13, 2023

A cost-effective, highly regioselective and metal-free version for the synthesis of indolizine derivatives by means Tf2O-mediated cascade reaction pyridyl-enaminones thiophenols/thioalcohols under mild conditions has been reported. Diverse electron-rich could be obtained in up to 94% yield via selective 1,4-addition vinyl iminium triflate tandem cyclization/aromatization, which allowed simultaneous construction C–N C–S/and one example C–Se bonds.

Language: Английский

Citations

15
Switchable Synthesis of Spirodihydroindolizines and Indolizines from Aurones and Pyridin-2-yl Active Methylene Compounds DOI
Quan Liu, Feng Wang,

Zeng‐Yang He

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(3), P. 1753 - 1761

Published: Jan. 22, 2024

A novel and flexible domino reaction of aurones with pyridin-2-yl active methylene compounds promoted by I2/BF3 has been developed to afford spirodihydroindolizines indolizines in a controllable manner. When the was performed 1,2-dichloroethane at 80 °C, variety were obtained, whereas it almost exclusively provided series when mixed solvent N,N-dimethylformamide relatively higher temperature 100 °C. Being metal-free, excellent product selectivity, high atom economy, good functional group tolerance, feasibility for large-scale synthesis are salient features methodology.

Language: Английский

Citations

5
Controlled and Site-Selective C–H/N–H Alkenylation, Dialkenylation, and Dehydrogenative β-Alkenylation of Various N-Heterocycles DOI
Yan Jin,

Suijie Zhong,

Chen Xu

et al.

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(7), P. 4840 - 4850

Published: March 19, 2024

Here, we report controlled and site-selective C–H alkenylation dialkenylation of indolizines pyrrolo[1,2-a]quinolines with β-alkoxyvinyl trifluoromethylketones under simple practical conditions. Moreover, this direct strategy can also be extended to imidazo[1,2-a]pyridines. Notably, without a transition metal external oxidant, efficient dehydrogenative β-alkenylation tertiary amines is presented.

Language: Английский

Citations

5
Transition metal-free annulative vinylene transfer via the 1,3-dipolar reaction of N-ylides: access to benzo-fused indolizines DOI

Limin Zhao,

Wen Li, Jiali Liu

et al.

Organic & Biomolecular Chemistry, Journal Year: 2022, Volume and Issue: 20(48), P. 9604 - 9608

Published: Jan. 1, 2022

An efficient metal-free annulative vinylene transfer protocol for the synthesis of benzo-fused indolizines via 1,3-dipolar cycloadditions N-ylides with carbonate has been developed. Vinylene serves as an acetylene surrogate without any external oxidant involved. This transformation leads to direct construction versatile indolizine derivatives in moderate good yields.

Language: Английский

Citations

19