Bio-based Green Solvent Research Articles

Sustainable synthesis of imidazoles using a catalyst-free approach and ethyl lactate as a bio-based green solvent in the Debus-Japp-Radziszewski reaction

A highly substituted family of imidazoles is effectively obtained through the Debus-Japp-Radziszewski reaction. In this process, benzil, ammonium acetate, and various benzaldehydes react in a particularly notable solvent: ethyl lactate (EL). This bio-based solvent, derived from biomass fermentation, stands out not only for its sustainable origin but also for its remarkable properties. Ethyl lactate is biodegradable, health-risk-free, is easily recyclable, and is non-corrosive, categorizing it as an exemplary green solvent. The multicomponent reaction, carried out under these conditions, eliminates the need for a catalyst, resulting in products with good yields. The isolation of the products is very simple, requiring only filtration, as they are insoluble in the solvent. In this way, this methodology aligns with various principles of green chemistry, emphasizing the strategic choice of ethyl lactate. This choice has a positive impact on the synthesis of imidazoles, well-known for their pharmacological properties.

Hydrogel-assisted microfluidic wet spinning of poly(lactic acid) fibers from a green and pro-crystallization spinning dope

Poly(lactic acid) (PLA) fibers have found a broad range of applications in medical textiles. While traditional spinning methods usually involve harsh conditions, such as high temperatureor toxic organic solvents, the challenges in producing PLA fibers via a green route are yet to be overcome. Herein, we described a new strategy for PLA fiber production, which combines the controlled and benign spinning conditions enabled by microfluidics and a novel green spinning dope with bio-sourced CyreneTMas a non-toxic solvent for PLA. This strategy is enabled by the in-situ formation of ahydrogel shell around the focused PLA/Cyrene™spinning dope stream. This hydrogel shell stabilizes the core stream and facilitates the solidification of the PLA fiber. Our hydrogel-assisted microfluidic wet spinning (HA-MWS) strategy represents the first-ever method that allows for the continuous room-temperature production of highly porous PLA fibers (porosity > 80 %) without the need for petroleum-based chemicals. We characterized the solution properties of the PLA/CyreneTMspinning dope and discovered that CyreneTMcan induce PLA crystallization, with resultant crystals acting as cross-linking centers for the spinning dope gelation. We then explored the microfluidic wet spinning process, using the spinning dope as the core flow and the alginate aqueous solution as the shell flow to achieve controlled fiber production. The resulting PLA fibers underwent comprehensive morphological, structural, and mechanical characterization. Our process enables the green productionofPLA fibers under mild conditions.More importantly, a bio-based green and pro-crystallization solvent was for the first time used to develop PLA spinning dope, which gives rise to a range of promising fiber properties (e.g. high porosity), which can broaden potential biomedical applications of PLA fibers.

Bio-based green solvent for metal-free aerobic oxidation of 5-hydroxymethylfurfural to 2,5-diformylfural over nitric acid-modified starch

The non-toxic biologic material of expanded corn starch (ECS)-supported nitric acid (ECS-HNO3 and ECS-NH2-HNO3) has been prepared via simple procedures. Both the materials are used as heterogeneous catalysts for the selective aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF) with an up to 98% yield in γ-butyrolactone (GBL, a bio-based green solvent) containing as little as 10% (v/v) acetic acid (AcOH) after less than 5 h under ambient pressure of dioxygen at 50 oC. The ECS-NH2-HNO3 proved to be more stable than ECS-HNO3 and was repeatedly used five times with almost no change in its catalytic performance.

Revisit to the synthesis of 1,2,3,4-tetrasubstituted pyrrole derivatives in lactic acid media as a green solvent and catalyst.

In this study, for the first time, lactic acid was used as a bio-based green catalyst and reaction medium for the synthesis of 1,2,3,4-tetrasubstituted pyrrole derivatives from one-pot three-component reaction of commercially available primary amines, 1,3-dicarbonyl compounds, and trans-β-nitrostyrene at room temperature. Thirty-three corresponding pyrroles, of which eight are novel and have been reported for the first time, were synthesized in high to excellent yields in lactic acid media and characterized by spectroscopic analysis. In all examined cases, lactic acid represented many advantages, including shorter reaction time, ease of product isolation, higher yields, no by-products, no chromatographic process, and lower volatility in the reaction. This bio-based green solvent can also be recycled and reused three times without loss of its efficiency as a catalyst and solvent.

The Perspective of Cooperative Hydrotropy on the Solubility in Aqueous Solutions of Cyrene

Cyrene is an emerging bio-based green solvent that has been shown to have the ability to increase the solubility of hydrophobic substances in water. Even though the water-Cyrene system is an attrac...

Solubility Enhancement of Hydrophobic Substances in Water/Cyrene Mixtures: A Computational Study

Cyrene, a recently introduced bio-based green solvent, behaves as a hydrotrope, greatly increasing the aqueous solubility of hydrophobic substances in water. Moreover, water, when present in small ...

Process synthesis and analysis of green plastic monomer production from cellulose

As a renewable building block, 2,5-furandicarboxylic acid (FDCA) is a potentially viable alternative to petro-based terephthalic acid (TPA). For the commercialization of FDCA production, economically feasible process development is crucial. In this study, we design a new catalytic conversion process for the production of the green plastic monomer (FDCA) and evaluate the economic feasibility of the process. In the proposed process, the FDCA is produced from cellulose using a bio-based green solvent composed of gamma-valerolactone (GVL) and H2O via three-step conversion involving cellulose hydrolysis, glucose dehydration and 5-hydroxymethylfurfural (HMF) oxidation subsequently. For the efficient recovery of solvents and products, the separation subsystem is designed and integrated with the conversion process. Moreover, to improve energy efficiency, a heat exchanger network combined with a heat pump is designed. The new process increases the FDCA productivity by 17% and reduces the total capital investment by 52.6% after optimization. Furthermore, this proposed process leads to the minimum selling price (MSP) of $1366/t for FDCA, which suggests that the proposed process for bio-based FDCA production is a promising approach to substitute petro-based TPA ($1445/t). The sensitivity analysis identifies that the main cost drivers are a feedstock price, steam price and discount rate, which should be investigated for the further improvement of the economics of the process.

γ-valerolactone (GVL) as a bio-based green solvent and ligand for iron-mediated AGET ATRP

AbstractIn this paper, γ-valerolactone (GVL), a bio-based polar solvent, was applied as green solvent for iron(III)-catalyzed AGET ATRP without any external ligand. GVL is a fully degradable, non-toxic green solvent and has complex ability to iron halide complexes through –OCO- group. GVL as the solvent and the ligand for AGET ATRP of MMA in a controlled manner, as proved by kinetic study, the low PDI values and the increase in polymer molecular weight versus monomer conversion. Chain re-initiation experiments and 1HNMR characterization were conducted to further confirm the living feature.

Synthesis of T-shaped Oxazolonaphthoimidazo[1,2-a]pyridines using Lactic Acid as Bio-based Green Solvent: An Insight into Photophysical Studies

Synthesis of T-shaped Oxazolonaphthoimidazo[1,2-<i>a</i>]pyridines using Lactic Acid as Bio-based Green Solvent: An Insight into Photophysical Studies

Ionic liquid as a promising biobased green solvent in combination with microwave irradiation for direct biodiesel production

The wet biomass microalgae of Nannochloropsis sp. was converted to biodiesel using direct transesterification (DT) by microwave technique and ionic liquid (IL) as the green solvent. Three different ionic liquids; 1-butyl-3-metyhlimidazolium chloride ([BMIM][Cl], 1-ethyl-3-methylimmidazolium methyl sulphate [EMIM][MeSO4] and 1-butyl-3-methylimidazolium trifluoromethane sulfonate [BMIM][CF3SO3]) and organic solvents (hexane and methanol) were used as co-solvents under microwave irradiation and their performances in terms of percentage disruption, cell walls ruptured and biodiesel yields were compared at different reaction times (5, 10 and 15min). [EMIM][MeSO4] showed highest percentage cell disruption (99.73%) and biodiesel yield (36.79% per dried biomass) after 15min of simultaneous reaction. The results demonstrated that simultaneous extraction-transesterification using ILs and microwave irradiation is a potential alternative method for biodiesel production.

KIO3-Catalyzed Aerobic Cross-Coupling Reactions of Enaminones and Thiophenols: Synthesis of Polyfunctionalized Alkenes by Metal-Free C-H Sulfenylation.

The synthesis of polyfunctionalized aminothioalkenes has been realized via the direct C-H sulfenylation of enaminones and analogous enamines. These cross-coupling reactions have been achieved by simple KIO3 catalysis under aerobic conditions without employing any transition metal catalyst or additional oxidant. The employment of bio-based green solvent ethyl lactate as the reaction medium constitutes another sustainable feature of the present work.

Efficient and Environmentally Benign Diversity Oriented Synthesis of 2, 3- dihydroquinazolin-4(1H)-ones Using GAAS As a Bio-based Green Solvent

Efficient and Environmentally Benign Diversity Oriented Synthesis of 2, 3- dihydroquinazolin-4(1H)-ones Using GAAS As a Bio-based Green Solvent

Lactic acid as an invaluable green solvent for ultrasound-assisted scalable synthesis of pyrrole derivatives

Lactic acid has been used as a bio-based green solvent to study the ultrasound-assisted scale-up synthesis. We report here, for the first time, on the novel and scalable process for synthesis of pyrrole derivatives in lactic acid solvent under ultrasonic radiation. Eighteen pyrrole derivatives have been synthesized in lactic acid solvent under ultrasonic radiation and characterized by 1H NMR, IR, ESI MS. The results show, under ultrasonic radiation, lactic acid solvent can overcome the scale-up challenges and exhibited many advantages, such as bio-based origin, shorter reaction time, lower volatility, higher yields, and ease of isolating the products.

Bio-based green solvent for the catalyst free oxidation of arylboronic acids into phenols

A bio-based green solvent, lactic acid is found to be an efficient reaction medium for the catalyst free oxidation of aryl boronic acids into phenols with aqueous hydrogen peroxide.

Synthesis of 5-Ethoxymethylfurfural from Fructose and Inulin Catalyzed by a Magnetically Recoverable Acid Catalyst.

A magnetically recoverable catalyst was conveniently synthesized by the immobilization of sulfonic acid on the surface of silica-encapsulated Fe3 O4 nanoparticles, and it was used to catalyze the conversion of fructose-based carbohydrates into 5-ethoxymethylfurfural (EMF). A high EMF yield of 89.3 % was obtained from the etherification of 5-hydroxymethylfurfural at 100 °C for 10 h. The one-pot conversion of fructose could produce EMF with a yield of 72.5 %. More importantly, EMF was also obtained in a satisfactory yield of 63.3 % when the polysaccharide inulin was used as the starting material. The excellent EMF yield showed that the catalyst had strong and sufficient acidic sites, which were responsible for the good catalytic performance. After the reaction, the catalyst could be readily removed from the reaction mixture by means of an external magnetic field, and the catalyst could be reused several times without significant loss in its catalytic activity. Incidentally, the product EMF was easily obtained through the evaporation of the solvent, ethanol, under reduced pressure at low temperature (ca. 40 °C), and the ethanol could also be reused. The integrated utilization of a biorenewable feedstock, magnetically recoverable catalyst, and bio-based green solvent is a typical example of an ideal green chemical process to produce potential liquid fuels.

Bio-based green solvent mediated disulfide synthesis via thiol couplings free of catalyst and additive

The bio-based green solvent ethyl lactate has been found to be a particularly efficient medium for oxidative coupling reactions of thiols yielding a broad array of disulfides. As a green solvent, ethyl lactate has shown an interesting promotion effect on the transformation by mediating corresponding reactions with high efficiency without using any catalyst or additive.

Lactic acid as an invaluable bio-based solvent for organic reactions

Lactic acid was used, for the first time, as a bio-based green solvent to promote some organic reactions, such as three-component reactions of styrenes, formaldehyde and an active phenolic compound or N,N-dialkylacetoacetamides, three-component reactions of diethyl acetylenedicarboxylate, anilines and aromatic aldehydes, aniline-catalyzed condensations between salicylaldehydes and diethyl acetylenedicarboxylate, and the synthesis of substituted quinolines through Friedlander annulation between 2′-aminoacetophenone and 1,3-dicarbonyl compounds. In these reactions, lactic acid solvent exhibited many advantages including bio-based origin, superior synthetic efficiency, ease of isolating the product and good recyclability of the reaction medium. The concept of using lactic acid as a green solvent not only enriches the diversity and versatility of bio-based green solvents, but also offers us an effective means for designing environmentally benign synthetic systems.