Sustainable Resource Recovery from Dairy Waste: A Case Study of Hydrothermal Co-liquefaction of Acid Whey and Anaerobic Digestate Mixture

Energy & Fuels, Journal Year: 2023, Volume and Issue: 37(4), P. 2897 - 2911

Published: Jan. 27, 2023

Uncontrolled emission of carbon and nutrients due to mismanagement dairy waste leads global warming, eutrophication water bodies, aerosol pollution, acidification ecosystems. We studied hydrothermal liquefaction (HTL) sustainably recover resources by converting the wastes into carbon-dense biocrude oil a nutrient-rich aqueous-phase coproduct. evaluated acid whey as an alternative source catalyst, replacing acetic acid, for HTL anaerobically digested cattle manure (manure digestate). Using well-designed experiments, we investigated effects several factors on product formation fate elements well underlying chemistry. The included reaction temperature (280–360 °C), time (10–50 min), mixing ratio digestate (AW/MD 0–2), amount additional required, that is, specified based final feedstock pH between 3.5 5.5. experimental results suggested following optimal conditions enhanced maximal nutrient yield in coproduct: AW/MD 1.21, mixture 4.5, 354 °C 21 min, respectively. Under such conditions, was 40–50% (equivalent 60–80% energy recovery) via cyclic acetalization, hydroxymethylation, isomerization, Piancatelli rearrangement, oxidation, condensation with heteroatom removal deoxygenation denitrogenation mechanisms. Moreover, these provided adequate solubilize Mg-carbonate Ca-phosphate minerals catalyzed deamination N-heterocyclics other nitrogenous compounds, producing higher recoverable Mg, NH3-N, P, K coproduct, 60–70, 30–40, ∼40, >95%, This study demonstrated potential using coprocessing measurably valorize biomass key component achieving circular bioeconomy industry.

Language: Английский

---

An Approach to Functionally Embellished o-Alkynylbenzoates or Furan-3(2H)-ones from Diynones and DMAD: Controlled Divergence and Product Selectivity

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(6), P. 3945 - 3953

Published: March 2, 2023

The discovery of reaction regime controlled product diversification in a one-pot between diynones and dimethyl-1,3-acetonedicarboxylate (DMAD) to selectively furnish either functionally unique pentasubstituted o-alkynylbenzoates or fully substituted furan-3(2H)-ones is delineated. potential these two versatile platforms enter new utilitarian chemical space has also been explored.

Language: Английский

---

Cyclization Reactions of In Situ-Generated Acyl Ketene with Ynones to Form Oxacycles

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(7), P. 4496 - 4502

Published: March 20, 2024

Acyl ketenes react with polar unsaturated functional groups to give unique heterocyclic rings, yet reactions unpolarized have not been reported. Herein, we describe two effective ring-forming between acetyl ketene and electron-deficient alkynes. The first reaction involves in situ tethering nucleophile-containing 1,3-diynones, which promotes sequential intramolecular 1,6/1,4-additions generate 2-methylene-2H-pyrans various yields (24–91%). other a zwitterionic intermediate generated from DABCO, undergoes Michael addition terminal alkynyl ketones 3-acyl-4-pyrones (11–79%).

Language: Английский

---

Metal Nanoparticle‐Catalyzed Alkyne Cyclization for the Synthesis of Heterocycles

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(14), P. 3085 - 3104

Published: May 22, 2024

Abstract Heterocycles are important compounds existed in diverse advanced chemicals, functional materials, bioactive molecules and natural products. Different strategies through transition metal‐catalyzed alkyne cyclization have been developed to synthesize various heterocycles. The merger of metal nanoparticle catalysis has emerged as an approach By using different kinds catalysts, such gold, silver, copper palladium nanoparticles, a number heterocycles prepared with high yield selectivity green, sustainable highly efficient manner. This review summarizes discusses recent achievements nanoparticle‐catalyzed for the synthesis

Language: Английский

---

The Construction of Polycyclic Pyridones via Ring-Opening Transformations of 3-hydroxy-3,4-dihydropyrido[2,1-c][1,4]oxazine-1,8-diones

Molecules, Journal Year: 2023, Volume and Issue: 28(3), P. 1285 - 1285

Published: Jan. 28, 2023

This work describes the synthesis of 3-hydroxy-3,4-dihydropyrido[2,1-c][1,4]oxazine-1,8-diones, their tautomerism, and reactivity towards binucleophiles. These molecules are novel convenient building-blocks for direct construction biologically important polycyclic pyridones via an oxazinone ring-opening transformation promoted with ammonium acetate or acetic acid. In case o-phenylenediamine, partial aromatization obtained heterocycles proceeded to form benzimidazole-fused (33-91%).

Language: Английский

---

Electronic Conductance and Thermopower of Cross-Conjugated and Skipped-Conjugated Molecules in Single-Molecule Junctions

The Journal of Physical Chemistry C, Journal Year: 2023, Volume and Issue: 127(28), P. 13751 - 13758

Published: July 6, 2023

We report a combined experimental and theoretical study of series thiomethyl (SMe) anchored cross-conjugated molecules featuring an acyclic central bridging ketone their analogous skipped-conjugated alcohol derivatives. Studies these in gold|single-molecule|gold junction using scanning tunneling microscopy-break techniques reveal similar conductance (G) value for both the partners. Theoretical studies based on density functional theory optimum geometries reason this similarity conductance, as predicted compounds varies more with tilt angle. Thermopower measurements higher Seebeck coefficient (S) relative to derivatives, particularly high S biphenyl derivative 3a (-15.6 μV/K), increase threefold compared its analog. The behavior quantum interference (QI) is found be constructive, though appearance destructive QI feature due degeneracy HOMO orbital may explain enhancement molecule.

Language: Английский

---

Regioselective Synthesis of 2‐Trimethylsilyl‐4H‐pyran‐4‐ones from 1‐Ethoxy(hydroxy)‐5‐(trimethylsilyl)pentenynones

European Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 26(34)

Published: Aug. 3, 2023

Abstract Exclusive formation of 5‐aryl‐2‐trimethylsilyl‐4 H ‐pyran‐4‐ones is accomplished by a regioselective cyclization 2‐aryl‐1‐ethoxy(hydroxy)‐5‐(trimethylsilyl)pent‐1‐en‐4‐yn‐3‐ones. This occurs in 6‐endo‐dig mode through addition to the β‐atom TMS substituted triple bond. The reaction was found be general for range ethoxyenynones upon heating glacial acetic acid and analogous hydroxyenynones diphenyl ether. Plausible mechanistic explanation possible post‐modifications resulting pyranones are offered.

Language: Английский

---

Lewis acid-catalyzed chemo- and stereoselective addition of pyrroles to skipped diynones: en route to novel pyrrole-based ketocyanine dyes and alkyne-tethered enones

Dyes and Pigments, Journal Year: 2024, Volume and Issue: 229, P. 112293 - 112293

Published: June 18, 2024

Language: Английский

---

Synthesis of Nitrogen- and Oxygen-Containing Heterocycles Catalysed by Metal Nanoparticles Reported in 2022

Synlett, Journal Year: 2024, Volume and Issue: 35(14), P. 1669 - 1697

Published: Jan. 3, 2024

Abstract The versatility of aza- and oxa-heterocyclic compounds has garnered significant attention in recent times. A large number currently approved pharmaceutical products include nitrogen- oxygen-containing heterocycles. Recent nanotechnological developments have propelled an upsurge the applications nanocatalysis for heterocyclic synthesis. Metal nanoparticles (MNPs) emerged as promising catalysts synthesis oxa-heterocycles owing to their unique physicochemical properties. Various MNPs including gold, silver, nickel palladium been evaluated catalytic activities different reaction types, cyclisation, coupling, hydrogenation oxidative transformations. exhibited remarkable efficiency when utilised under optimal conditions. These showcased high reusability recyclability, yielding satisfactory amounts desired compound. present work provides a detailed overview advances area MNP-assisted synthetic construction oxa-heterocycles, published during previous calendar year, 2022. review serves valuable resource also paves way future investigations development novel strategies heterocycle 1 Introduction 2 Nanocatalysis 3 Aza- Oxa-Heterocycle Synthesis Catalysed by 3.1 AuNPs 3.2 CuNPs 3.3 CoNPs 3.4 FeNPs 3.5 NiNPs 3.6 PdNPs 3.7 PtNPs 3.8 SiNPs 3.9 ZnNPs 3.10 Bimetallic NPs 3.11 Other 4 Summary Outlook

Language: Английский

---

Synergistic Rh(II)- and Zn(II)-Catalyzed [3 + 3] Annulation of Diazoenals and α-Hydroxy Ketones for the Direct Synthesis of 2H-Pyrans, A Gateway Toward γ-Pyrones

Organic Letters, Journal Year: 2024, Volume and Issue: 26(43), P. 9227 - 9232

Published: Oct. 21, 2024

A new synergistic Rh(II)/Zn(II)-catalyzed [3 + 3] annulation has been developed between diazoenals and α-hydroxy ketones enabling the direct synthesis of 4-formyl-2H-pyrans. The reaction involves formation protic oxonium ylides from highly electrophilic Rh-enalcarbenoids followed by Zn-templated regioselective intramolecular aldol condensation. Subsequent investigations demonstrated that 4-formyl-2H-pyrans are unique precursors γ-pyrones. γ-pyrones were obtained via Et3N-mediated oxidative deformylation. Further, triflic-acid-promoted double Schmidt provides synthetically important carboxamide-substituted 4-cyano 2H-pyrans.

Language: Английский

---