A review on DBU-mediated organic transformations

Green Chemistry Letters and Reviews, Journal Year: 2022, Volume and Issue: 15(3), P. 765 - 795

Published: July 3, 2022

1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) has received a significant importance in organic synthesis during recent years because of its interesting ability to catalyze reaction sufficiently at mild conditions. DBU can work as catalyst under simple conditions inducing the operational simplicity experimental procedures by reducing side products and waste. The notable advantages these cases include less expensive which is commercially readily available, easy handle, most importantly recoverable. been explored for several practical methodologies highly useful wide variety materials. selectivity (chemo-, regio-, stereo-) reactions impressive applicable modern chemical transformations. possesses enhanced basic properties high mechanical well thermal stability. In years, large number transformations have carried out using catalyst. successfully employed conduct including usual modifications, cyclizations, eliminations, esterifications, condensation reactions, multicomponent etc. fact, last few decades, tremendous interest sparked various promoted publications appeared literature. Since catalyzed recently proven be important we review this article protocols

Language: Английский

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Base-Mediated Cascade Lactonization/1,3-Dipolar Cycloaddition Pathway for the One-Pot Assembly of Coumarin-Functionalized Pyrrolo[2,1-a]isoquinolines

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(12), P. 8420 - 8434

Published: June 5, 2024

An elegant and highly concise strategy for the construction of coumarin-functionalized pyrrolo[2,1-a]isoquinolines from available propargylamines isoquinolinium N-ylides has been disclosed. In this reaction, acted as a C2 synthon to form coumarin ring well 1,3-dipole construct pyrrole in single pot. This cascade process involves 1,4-conjugate addition/lactonization/1,3-dipolar cycloaddition four chemical bonds (one C–O bond three C–C bonds) two new heterocyclic skeletons. Additionally, most these compounds showed good fluorescence properties exhibited high molar extinction coefficient large Stokes shifts.

Language: Английский

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BF₃·OEt₂ Catalyzed Cascade [4 + 2] Benzannulation of Vinyloxiranes with Coumarins to Construct Benzocoumarin Derivatives

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(13), P. 9462 - 9472

Published: June 13, 2024

A BF

Language: Английский

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Base‐Mediated [4+1] Annulation Strategy for Modular Assembly of Alkynyl/Carboxylated Dihydrobenzofurans

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

Published: March 17, 2025

Abstract An efficient and operational [4+1] annulation strategy toward functional dihydrobenzofurans from 2‐bromomalonates in situ generated alkynyl o ‐quinone methides (from ‐hydroxyphenyl propargylamines) has been developed. Without the need for pre‐dried solvent inert atmosphere protection, a broad range of substituted propargylamines are well‐tolerated, producing expected alkynyl/carboxylated with good to high yields. Furthermore, gram‐scale synthesis valuable alkenyl/carboxylated construction were conducted provide great potential value medicinal chemistry other related disciplines.

Language: Английский

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An expeditious FeCl₃-catalyzed cascade 1,4-conjugate addition/annulation/1,5-H shift sequence for modular access of all-pyrano-moiety-substituted chromenes

Chemical Science, Journal Year: 2022, Volume and Issue: 13(45), P. 13617 - 13622

Published: Jan. 1, 2022

An operationally simple protocol is described for the facile, modular and regioselective access of all-pyrano-moiety-substituted iminochromenes, particularly under undried acetonitrile air atmosphere.

Language: Английский

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Copper-Catalyzed Cascade Annulation of o-Hydroxyphenyl Propargylamines with Pyrazolin-5-ones to Access Pyrano[2,3-c]pyrazoles

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(9), P. 5795 - 5803

Published: April 20, 2022

An efficient copper-catalyzed cascade annulation of o-hydroxyphenyl propargylamines and pyrazolin-5-ones is described. This methodology leads to the rapid assembly a series valuable pyrano[2,3-c]pyrazoles with good yields across wide range substrates in simple fashion. novel reaction involves formation alkynyl ortho-quinone methides, 1,4-conjugate addition, subsequent 6-endo cyclization process. The mechanistic elucidation well supported by control experiment literature precedents.

Language: Английский

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Cascade Annulation Strategy for Expeditious Assembly of Hydroxybenzo[c]chromen-6-ones and Their Photophysical Property Studies

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(23), P. 16609 - 16620

Published: Nov. 18, 2023

A 1,8-diazabicyclo[5.4.0]undec-7-ene-promoted cascade double-annulation of ortho-alkynyl quinone methide (in situ generated from modular propargylamine) for constructing 2-aryl-4-hydroxybenzo[c]chromen-6-ones is developed. This synthetic strategy offers remarkable operational simplicity as it allows the use benchtop-grade solvents without need predrying measures and inert atmosphere protection. Additionally, demonstrates good functional group compatibility. The photophysical properties these compounds were also examined, revealing bright fluorescence with high quantum yields.

Language: Английский

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Visible-Light-Induced Tandem Radical Brominative Addition/Cyclization of Activated Alkynes with CBr₄ for the Synthesis of 3-Bromocoumarins

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 88(1), P. 647 - 652

Published: Dec. 8, 2022

A visible-light-induced tandem radical brominative addition/spiro-cyclization/1,2-ester migration of activated alkynes with CBr4 is developed. This protocol features good functional group tolerance, operational simplicity, and mild reaction conditions without the use catalysts external additives, providing easy access to valuable 3-bromocoumarins in generally high yields.

Language: Английский

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Modular three-component synthesis of 6H-benzochromenone based blue luminogens under catalyst- and solvent-free conditions

New Journal of Chemistry, Journal Year: 2024, Volume and Issue: 48(5), P. 2175 - 2182

Published: Jan. 1, 2024

Highly efficient synthesis of benzochromenone based blue luminogens via a three-component reaction 2-hydroxychalcones, primary amines and β-ketoesters was demonstrated.

Language: Английский

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Oxidative [4+2] Annulation of Pyrrole‐2‐carbaldehyde Derivatives with o‐Hydroxyphenyl Propargylamines: Syntheses of 5,6,7‐Trisubstituted Indolizines

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(63)

Published: Aug. 23, 2024

Abstract A base promoted oxidative [4+2] annulation of pyrrole‐2‐carbaldehyde derivatives with o ‐hydroxyphenyl propargylamines for the synthesis highly substituted indolizines has been developed. Using DBN as base, a broad range 5,6,7‐trisubstituted have prepared in good to excellent yields under mild conditions, and many useful functional groups can be tolerated.

Language: Английский

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