Green Metrics and Sustainability in Photocatalysis

ChemCatChem, Journal Year: 2024, Volume and Issue: 16(14)

Published: Jan. 5, 2024

Abstract In the past century, significant advancements in synthetic chemistry undeniably contributed to wellness of mankind, from development new drugs design materials for energy production and storage. However, this technological progress has also brought forth challenges, emphasizing urgent need rethink more environmentally friendly approaches. Review a critical comprehensive analysis sustainability preparation commonly used photocatalysts is performed, by employing mass‐based metrics. Additionally, comparative evaluation made between some selected photocatalytic protocols traditional reactions not relying on light. The objective quantitatively evaluate claims greenness associated with photocatalysis, exploring real impact procedures waste generation. This quantitative approach provides insights into broader concept sustainable processes, challenging assumptions encouraging rigorous green catalysis. Furthermore, toxicity involved species availability required chemical elements commented provide global perspective analyzed transformations. results shed light true environmental footprint photocatalysis reveal that notion can sometimes be overstated.

Language: Английский

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Palladium-Catalyzed [3 + 2] Cycloaddition of 4-Vinyl-4-butyrolactones with Ketenes Generated in Situ from Acyl Chlorides: A Method for the Synthesis of Dihydrofurans

Organic Letters, Journal Year: 2024, Volume and Issue: 26(10), P. 2057 - 2061

Published: March 1, 2024

In this paper, palladium-catalyzed [3 + 2] cycloaddition of 4-vinyl-4-butyrolactones with ketenes generated from easily available acyl chlorides was achieved. With Pd2(dba)3·CHCl3/XantPhos as the catalyst, reaction proceeded smoothly under mild conditions, affording a series 2,3-dihydrofurans in moderate to high yields. The scale-up and further transformations products are demonstrated, plausible mechanism is proposed well.

Language: Английский

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α‐Halocarbonyls as a Valuable Functionalized Tertiary Alkyl Source

ChemistryOpen, Journal Year: 2024, Volume and Issue: unknown

Published: July 11, 2024

Abstract This review introduces the synthetic organic chemical value of α‐bromocarbonyl compounds with tertiary carbons. compound a carbon has been used primarily only as radical initiator in atom transfer polymerization (ATRP) reactions. However, recent development photo‐radical reactions (around 2010), research on use alkyl precursors became popular 2012). As more examples were reported, studied not radicals but also for their applications organometallic and ionic That is, act nucleophiles well electrophiles. The carbonyl group is attractive because it allows skeleton to be converted after reaction, being applied total synthesis. In our survey until 2022, can perform full range necessary synthesis, including multi‐component reactions, cross‐coupling, substitution, cyclization, rearrangement, stereospecific asymmetric α‐Bromocarbonyl have created new trend alkylation, which then had limited reaction patterns focuses how chemistry.

Language: Английский

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Highly diastereoselective synthesis of annulated 2‐acyl‐2,3‐dihydrofurans

Journal of the Chinese Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: March 24, 2025

Abstract A simple and convenient method to synthesize annulated 2‐acyl‐2,3‐dihydrofuran derivatives by Michael addition‐alkylation reaction of α‐bromochalcones 5,5‐dimethylcyclohexane‐1,3‐dione is described. This transformation was well compatible with various α‐bromochalcones, the corresponding 2‐acyl‐2,3‐dihydrofurans were obtained in yields up 98%.

Language: Английский

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Towards a More Sustainable Photocatalyzed α‐Arylation of Amines: Green Solvents, Catalyst Recycling and Low Loading

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(2), P. 252 - 262

Published: Jan. 7, 2023

Abstract A more sustainable and efficient protocol for the photocatalytic α‐amino arylation promoted by fac ‐Ir(ppy) 3 was developed. Three noteworthy results were achieved: i) replacement of toxic medium DMA with greener solvents NBP NHP, concurrent improvement process efficiency lowering both amine base amount; ii) development a recycling solvent NHP commercially available costly photocatalyst , achieving environmental economic benefits. This approach to recovery avoids very demanding catalyst structural modifications; iii) in green proved be scalable up 10 mmol limiting reagent, maintaining excellent performance also loading down 0.05 mol%. is first example α‐arylation amines such low amount catalyst. Lastly, versatility this demonstrated extending use another photoredox process. magnified image

Language: Английский

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Asymmetric synthesis of binaphthyls through photocatalytic cross-coupling and organocatalytic kinetic resolution

Science China Chemistry, Journal Year: 2022, Volume and Issue: 65(6), P. 1142 - 1148

Published: May 18, 2022

Language: Английский

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Selective Hydrofunctionalization of N-Allenyl Derivatives with Heteronucleophiles Catalyzed by Brønsted Acids

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(4), P. 2320 - 2342

Published: Feb. 1, 2024

In this study, we present a novel and environmentally sustainable protocol for the γ-hydrofunctionalization of N-allenyl compounds using various heteronucleophiles catalyzed solely by simple Brønsted acids. The method displays remarkable attributes, highlighting its sustainability, efficiency, regio- stereoselectivity, as well versatile applicability to diverse heteroatom-containing enamides. Notably, our approach eliminates need metal catalysts toxic solvents, representing significant advancement in greener chemistry practices. We demonstrate broad scope successfully scaling up reactions gram-scale syntheses, underscoring robustness potential industrial implementation. resulting γ-heterosubstituted enamides offer new possibilities further synthetic transformations, yielding highly functionalized with applications. Mechanistic investigations reveal pivotal role CSA catalyst, enabling alcohol addition via covalent activation mode.

Language: Английский

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Allenamides Playing Domino: A Redox‐Neutral Photocatalytic Synthesis of Functionalized 2‐Aminofurans

Advanced Synthesis & Catalysis, Journal Year: 2021, Volume and Issue: 364(2), P. 362 - 371

Published: Oct. 7, 2021

Abstract A photoredox catalytic synthesis of functionalized 2‐aminofurans is proposed starting from α‐halo carbonyl substrates and N ‐allenamides. The protocol proves to be efficient sustainable thanks to: i ) the use visible light as green energy source, ii redox‐neutral nature transformation, allowing avoid additives strong oxidants, iii mild reaction conditions functional groups tolerance, iv low photocatalyst loading absence excess reagents, v one‐pot formation three new bonds in a domino sequence. According our mechanistic hypothesis, transformation configured double radical‐polar crossover reaction, which excited, oxidized reduced twice for each molecule 2‐aminofuran produced. novelty designed synthetic approach also lies ‐allenamides substrates, which, after addition first electrophilic radical, preserve further reactive π‐system, making possible second α‐keto radical enabling installation keto functionality at remote position. good yields, broad scope, possibility synthetically elaborate obtained furans make this particularly promising construction useful products. magnified image

Language: Английский

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Reductive Denitrogenation of Six‐membered Cyclic Nitronates to Densely Substituted Dihydrofurans with Raney® Nickel/AcOH System

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(17), P. 2850 - 2857

Published: July 18, 2023

Abstract A protocol for the synthesis of 2,3‐dihydrofurans by reductive denitrogenation/ring contraction 6‐membered cyclic nitronates was developed. The process utilizes cheap Raney® nickel both as catalyst and stoichiometric agent without need high‐pressure equipment. products are formed in high purity column chromatography is often not required. Studies on substrate scope, functional group tolerance, mechanism were performed. developed approach provides a straightforward two‐step access to densely substituted from nitrostyrenes alkenes.

Language: Английский

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The Chameleonic Nature of the Nitro Group Applied to a Base-Promoted Cascade Reaction To Afford Indane-Fused Dihydrofurans

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(13), P. 8150 - 8162

Published: June 21, 2023

We disclose a Michael/Conia-ene/SN2 cascade reaction for the synthesis of Indane-fused dihydrofurans from 1,3-dicarbonyl compounds and 2-alkynylnitrostyrenes promoted by potassium carbonate in DMSO at room temperature. In this reaction, nitro group has chameleonic role, first as an electron-withdrawing Michael addition, then nitronate behaves nucleophile, finally, allylic acts leaving group. The product is obtained single diastereomer, affording up to 82% with 1,3-keto esters 58% 1,3-diketones. Furthermore, DFT calculations mechanism explained chemoselective addition over enolate unactivated triple bond, being highly endothermic.

Language: Английский

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