Rapid and practical access to diverse quindolines by catalyst-free and regioselectivity-reversed Povarov reaction

Cell Reports Physical Science, Journal Year: 2021, Volume and Issue: 2(6), P. 100448 - 100448

Published: June 1, 2021

The Povarov reaction, a formal [4 + 2] cycloaddition between N-aryl imines and electron-rich dienophiles, has been defined as an efficient method to approach tetrahydroquinolines well established in the past decades. In general, heterosubstituted alkenes have served most popular dienophiles achieve exclusive regioselectivity. However, use of Lewis acids Brønsted catalysts is required these transformations, and, our knowledge, reaction alkynes not reported. Here, we disclose catalyst-free formyl-ynamides with anilines for rapid practical synthesis diverse range valuable quindolines, which only represents first ynamides best knowledge but also constitutes very rare example ynamide cyclization reaction. This [1 2 3] annulation shows reversed regioselectivity compared previous protocols.

Language: Английский

---

The Intramolecular Povarov Tool in the Construction of Fused Nitrogen-Containing Heterocycles

Topics in Current Chemistry, Journal Year: 2023, Volume and Issue: 381(4)

Published: May 30, 2023

Abstract Nitrogen heterocycles are part of the structure natural products and agents with important biological activity, such as antiviral, antibiotic, antitumor drugs. For this reason, heterocyclic compounds one today’s most desirable synthetic targets Povarov reaction is a powerful tool for construction highly functionalized systems. This process involves an aromatic amine, carbonyl compound, olefin or acetylene to give rise formation nitrogen-containing heterocycle. review illustrates advances in aspects intramolecular intricate polyheterocyclic compounds. original presents research done field, references works by internationally relevant groups on current topic, covering literature from 1992 2022. The reactions described here according key processes involved, using different combinations heteroaromatic amines, aliphatic, aromatic, aldehydes. Some catalytic promoted transition metals detailed, well oxidative some asymmetric processes.

Language: Английский

---

FeCl₃/KI‐Catalyzed Tandem Oxidative Cyclization for Switchable Total Synthesis of Luotonin A, B and Derivatives

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(6), P. 1348 - 1355

Published: Jan. 13, 2024

Abstract A total synthesis strategy was developed for the of luotonin A, B and their analogues using synergistic FeCl 3 /KI‐catalyzed oxidative cyclization. This protocol utilizes cheap widely available N ‐propargyl 2‐methyl‐quinazolinones arylamines under mild conditions, it has a wide substrate scope high atom economy. Different natural products (luotonin derivatives) can be synthesized via unique switchable approach. Further transformations from to E structural modification demonstrate potential applications this method. Moreover, camptothecin also modified with reported afford hydroxyl‐substituted product.

Language: Английский

---

The Chemistry of Aldehydes and Ketones in the Synthesis of Heterocycles - Historical Reactions with a New and Green Perspective

Current Organic Chemistry, Journal Year: 2024, Volume and Issue: 28(13), P. 1023 - 1045

Published: March 19, 2024

Abstract: The reactivity of aldehydes and ketones carries great potential for multicomponent heterocyclizations. These reactions are convergent highly versatile in the development synthetic methodologies compound families, displaying variations substituents their structures. Therefore, they have been regarded as an important tool field Green Chemistry. Furthermore, prove to be very useful studies biological activity, where small structural modifications can result significant differences. Many heterocyclizations date back mid-19th early 20th centuries. In this review, we aim demonstrate, through some these reactions, continuously growing improvements concerning development. Additionally, present original reported, enabling us appreciate evolution chemical representations over years until reaching standardization today.

Language: Английский

---

Regio- and Stereoselective Hydrochlorination/Cyclization of 1,n-Enynes by FeCl₃ Catalysis

Organic Letters, Journal Year: 2023, Volume and Issue: 25(23), P. 4359 - 4365

Published: June 7, 2023

A highly regio- and stereoselective hydrochlorination/cyclization of enynes has been reported by FeCl3 catalysis. variety undergo this cyclization transformation with acetic chloride as the chlorine source H2O providing protons via a cationic pathway. This protocol provides cheap, simple, stereospecific, effective to afford heterocyclic alkenyl compounds Z isomers high yields (≤98%) regioselectivity.

Language: Английский

---

Environmentally benign synthesis of 2,4-diarylquinolines under metal- & solvent-free conditions

Tetrahedron Letters, Journal Year: 2023, Volume and Issue: 120, P. 154433 - 154433

Published: March 8, 2023

Language: Английский

---

Iron-catalyzed divergent approach to naphthyridinones and quinolinones: leveraging Povarov and carbonyl-alkyne metathesis reactions of electron deficient alkynes

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(21), P. 5505 - 5511

Published: Jan. 1, 2023

We have successfully developed a novel synthetic route for the synthesis of naphthyridinones.

Language: Английский

---

π-Expanded azaullazines: synthesis of quinolino-azaullazines by Povarov reaction and cycloisomerisation

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(10), P. 2027 - 2042

Published: Jan. 1, 2024

Quinolino-azaullazines were prepared by combination of Pd catalyzed cross-coupling with Povarov and cycloisomerisation reactions. They show intramolecular charge transfer properties that can be tuned the substitution pattern.

Language: Английский

---

Iron-catalyzed alkyne–carbonyl metathesis for the synthesis of 6,7-dihydro-5H-dibenzo[c,e]azonines

Organic & Biomolecular Chemistry, Journal Year: 2021, Volume and Issue: 19(48), P. 10549 - 10553

Published: Jan. 1, 2021

The synthesis of nine-membered rings via alkyne-carbonyl metathesis is reported. alkyne and acetal units contained in a biaryl substrate undergo the intramolecular reaction under FeCl3-catalysis to furnish unexplored 6,7-dihydro-5H-dibenzo[c,e]azonines. method provides an alternative existing routes with cheap, non-toxic iron catalysts milder conditions.

Language: Английский

---

Bischler–Napieralski Synthesis of Polycyclic N-Heteroaromatics Based on Tf₂O-Promoted Electrophilic Activation of N-Aryl-2-Propynamides

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(6), P. 4124 - 4133

Published: March 7, 2022

2-Propynamides have been never used as substrates in classic and Tf2O-promoted Bischler-Napieralski reactions. In this article, a novel tandem synthesis of benzo[a]acridines is developed from N-aryl-2-propynamides alkynes consisting intermolecular reaction TfOH-promoted intramolecular Friedel-Crafts reaction.

Language: Английский

---