One-pot Conversion Research Articles

One-pot catalytic conversion of cellulose biomass to bioethanol at low pressure and temperature conditions: H2O as a self-hydrolytic agent

One-pot catalytic conversion of cellulose biomass to bioethanol at low pressure and temperature conditions: H2O as a self-hydrolytic agent

Chemoselective Pd-Based Dyotropic Rearrangement: Fluorocyclization and Regioselective Wacker Reaction of Homoallylic Amides.

Fluorocyclization of alkenes tethered with a pronucleophile is an efficient transformation that converts easily accessible starting materials to fluorinated heterocycles in a single step. We report herein an unprecedented Pd(II)-catalyzed oxidative domino process that transforms homoallylic amides to 5,6-dihydro-4H-1,3-oxazines through a domino oxypalladation/PdII-oxidation/dyotropic rearrangement/reductive elimination sequence. Three chemical bonds are created under these operationally simple conditions. Taking advantage of the facile hydrolysis of the α-fluoro tertiary alkyl ether under acidic conditions, a one-pot conversion of homoallylic amides to homologated ketones is subsequently developed, which represents a rare example of regioselective Wacker oxidation reaction of 1,1-disubstituted alkenes.

Bis(2-butoxyethyl) Ether-Promoted O2-Mediated Oxidation of Alkyl Aromatics to Ketones under Clean Conditions.

Conventional oxidation processes for alkyl aromatics to ketones employ oxidants that tend to generate harmful byproducts and cause severe equipment corrosion, ultimately creating critical environmental problems. Thus, in this study, a practical, efficient, and green method was developed for the synthesis of aromatic ketones by applying a bis(2-butoxyethyl) ether/O2 system under external catalyst-, additive-, and base-free conditions. This O2-mediated oxidation system can tolerate various functional groups and is suitable for large-scale synthesis. Diverse target ketones were prepared under clean conditions in moderate-to-high yields. The late-stage functionalization of drug derivatives with the corresponding ketones and one-pot sequential chemical conversions to ketone downstream products further broaden the application prospects of this approach.

Facile One-Pot Conversion of (poly)phenols to Diverse (hetero)aryl Compounds by Suzuki Coupling Reaction: A Modified Approach for the Synthesis of Coumarin- and Equol-Based Compounds as Potential Antioxidants.

A series of 16 (hetero)aryl compounds based on coumarin and equol has been efficiently synthesized by exploring the palladium-catalyzed Suzuki cross-coupling reactions. Polyphenol based on coumarin (4-methyl-7-hydroxy coumarin) was initially converted to corresponding coumarin imidazylate and then subjected to Suzuki coupling reaction with 4-methoxyphenylboronic acid to obtain the coupled product. This modified approach was later developed into a one-pot methodology by directly reacting the polyphenol with 1,1-sulfonyldiimidazole (SDI) and boronic acid in situ to obtain the Suzuki coupled product in one step. Moreover, an array of (poly)phenols based on coumarin and equol were later converted to diverse (hetero)aryl compounds by this optimized step-economic protocol. The synthesized compounds were then subjected to the screening of their potential antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. In our investigation, the compounds 4ah, 4eh, 4gh and 4hh exhibited promising antioxidant potential when compared to the reference standard, butylated hydroxytoluene (BHT). Structure activity relationship (SAR) studies revealed the importance of the presence of electron-donating substituents in enhancing the antioxidant activity of the synthesized compounds.

Modular alkene synthesis from carboxylic acids, alcohols and alkanes via integrated photocatalysis.

Alkenes serve as versatile building blocks in diverse organic transformations. Despite notable advancements in olefination methods, a general strategy for the direct conversion of carboxylic acids, alcohols and alkanes into alkenes remains a formidable challenge owing to their inherent reactivity disparities. Here we demonstrate an integrated photochemical strategy that facilitates a one-pot conversion of these fundamental building blocks into alkenes through a sequential C(sp3)-C(sp3) bond formation-fragmentation process, utilizing an easily accessible and recyclable phenyl vinyl ketone as the 'olefination reagent'. This practical method not only offers an unparalleled paradigm for accessing value-added alkenes from abundant and inexpensive starting materials but also showcases its versatility through various complex scenarios, including late-stage on-demand olefination of multifunctional molecules, chain homologation of acids and concise syntheses of bioactive molecules. Moreover, initiating from carboxylic acids, alcohols and alkanes, this protocol presents a complementary approach to traditional olefination methods, making it a highly valuable addition to the research toolkit for alkene synthesis.

One-pot, Solvent Free Synthesis of2,5-Furandicarboxylic Acid from Deep Eutectic Mixtures of Sugars as Mediated by Bifunctional Catalyst.

Currently one-pot conversion of sugars to 2,5-furandicarboxylic acid (FDCA) is of significant interest due to the attainability of sugars as a feedstock and the enormous potential of FDCA as a bioplastic monomer. However, it remains challenging to construct efficient catalysts for this process. In this study, Co3O4species were anchored to a sulfonated covalent organic framework thus affording a bifunctional catalyst (Co3O4@COF-SO3H). The sulfonic acid sites dehydrate sugars to 5-hydroxymethylfurfural (HMF), which is next oxidized to FDCA as catalyzed by the Co3O4species. Such a process was applied in the conversion of various binary and ternary deep eutectic mixtures involving choline chloride and sugars without additional solvent. The maximum FDCA yield of 84% was obtained using glucose-fructose eutectic mixture as the substrates. Moreover, the catalyst was recyclable and stable under the applied reaction conditions. Our process eliminates the employment of organic solvents and expensive noble metal catalysts, resulting in green and economic biomass conversions.

One-pot cascade conversion of furfural to isopropyl levulinate catalyzed by sulfonic acid-functionalized UiO-66

A porous sulfonic acid-functionalized zirconium-based metal–organic framework possessing both Lewis acid and Brønsted acid sites (UiO-66-SO3H) was synthesized and tested for the selective conversion of furfural (FUR) to isopropyl levulinate (IPL) through one-pot cascade reaction. UiO-66-SO3H exhibited excellent catalytic performance, and the conversion of FUR as well as the yield and selectivity of IPL reached 96.4 %, 86.0 %, and 89.2 %, respectively. UiO-66-SO3H could be simply recovered and reused, but the catalytic performance was significantly decreased. The FUR conversion and IPL yield dropped to 73.8 % and 65.1 %, respectively, after 1 cycle, and the reason for the decrease in the catalyst activity were also investigated. It was found that the decrease was mainly caused by the loss of some −SO3H groups, and the cyclic performance of UiO-66-SO3H could be restored by supplementing a small amount of BDC-SO3Na. A plausible mechanism for the selective synthesis of IPL from FUR was proposed, wherein both Lewis acid and Brønsted acid sites played important roles. This work provides guidance for the selective conversion of FUR into IPL, and the high-valued utilization of biomass and its derivatives.

One-pot enantioselective synthesis of chiral phenyllactic acids by combining stereocomplementary d- and l-lactate dehydrogenases with multi-enzyme expression fine-tuning

Chiral phenyllactic acid (PLA) is a new type of antiseptic agent and a valuable precursor for active ingredients in pharmaceuticals and agrochemicals. In this study, we designed a multi-enzyme cascade that combined stereocomplementary d- and l-lactate dehydrogenases with threonine aldolase, phenylserine dehydratase, and formate dehydrogenase for the one-pot conversion of achiral glycine and benzaldehyde to synthesize d-PLA and l-PLA. To overcome the imbalance of multi-enzymes in a single cell, two enzyme modules, overexpressing four enzymes, were assembled in Escherichia coli cells to construct whole-cell catalysis systems (WCCSs). Furthermore, by optimizing reaction conditions and components, recombinant E. coli (WCCS 26) was able to produce 100 mM d-PLA with >99 % ee using a fed-batch strategy, while E. coli (WCCS 60) produced 47.2 mM l-PLA with >99 % ee. This study presents a sustainable and efficient method for synthesizing chiral PLAs from food-grade achiral starting materials.

One-Pot Biocatalytic Conversion of Chemically Inert Hydrocarbons into Chiral Amino Acids through Internal Cofactor and H2O2 Recycling.

Chemically inert hydrocarbons are the primary feedstocks used in the petrochemical industry and can be converted into more intricate and valuable chemicals. However, two major challenges impede this conversion process: selective activation of C-H bonds in hydrocarbons and systematic functionalization required to synthesize complex structures. To address these issues, we developed a multi-enzyme cascade conversion system based on internal cofactor and H2O2 recycling to achieve the one-pot deep conversion from heptane to chiral (S)-2-aminoheptanoic acid under mild conditions. First, a hydrogen-borrowing-cycle-based NADH regeneration method and H2O2in situ generation and consumption strategy were applied to realize selective C-H bond oxyfunctionalization, converting heptane into 2-hydroxyheptanoic acid. Integrating subsequent reductive amination driven by the second hydrogen-borrowing cycle, (S)-2-aminoheptanoic acid was finally accumulated at 4.57 mM with eep > 99%. Hexane, octane, 2-methylheptane, and butylbenzene were also successfully converted into the corresponding chiral amino acids with eep > 99%. Overall, the conversion system employed internal cofactor and H2O2 recycling, with O2 as the oxidant and ammonium as the amination reagent to fulfill the enzymatic conversion from chemically inert hydrocarbons into chiral amino acids under environmentally friendly conditions, which is a highly challenging transformation in traditional organic synthesis.

Characterization of a novel cellobiose phosphorylase with broad optimal pH range from a tailings pond macrogenomic library

Glucose-1-phosphate, a crucial pharmaceutical intermediate, can be generated through the synergistic transformation of lignocellulose using cellulase and cellobiose phosphorylase (CBP), thus holding promise for a profitable biorefinery process. However, the reported optimal pH range of CBPs (6.0–7.5) does not align with that of cellulase (4.8), resulting in suboptimal efficiency in the one-pot conversion of cellulose to glucose-1-phosphate. In this study, we identified a novel cellobiose phosphorylase, CBP1942, comprising 811 amino acid residues (92.5 kDa), in tailing pond macrogenomes, exhibiting identity of 60% to 75% with reported CBPs. CBP1942 was efficiently expressed in E. coli BL21 and purified with His tagging. It maintains over 90% enzyme activity across pH 4–9. Compared to the benchmark CtCBP (GenBank ID: AAL67138.1), CBP1942 displays a 1.2-fold increase in specific enzyme activity at the optimal cellulase temperature (50 °C), indicating its superior suitability for cellulase compounding. CBP1942 exhibits Km and kcat values of 6.69 mM and 8.83 s−1, respectively, with a kcat/Km ratio 6.6 times higher than CtCBP, suggesting superior catalytic efficiency. Notably, CBP1942 shows remarkable thermal stability, retaining 94.67% enzyme activity after 3 h at 50 °C, while CtCBP retains only 78.33%. Additionally, CBP1942 complexed with cellulase enhances the conversion of corn stover, resulting in a 6.2-fold increase in glucose-1-phosphate yield compared to CtCBP. These findings indicate CBP1942’s potential as an industrial enzyme for corn stover conversion to glucose-1-phosphate.

Zirconium Phosphate-Pillared Zeolite MCM-36 for Green Production of γ-Valerolactone from Levulinic Acid via Catalytic Transfer Hydrogenation.

γ-valerolactone (GVL), derived from biomass, is a crucial platform compound for biofuel synthesis and various industrial applications. Current methods for synthesizing GVL involve expensive catalysts and high-pressure hydrogen, prompting the search for greener alternatives. This study focuses on a novel zirconium phosphate (ZrP)-pillared zeolite MCM-36 derivative catalyst for converting levulinic acid (LA) to GVL using alcohol as a hydrogen source. The incorporation of ZrP significantly contributes to mesoporosity and greatly enhances the acidity of the catalysts. Additionally, we employed 31P MAS NMR to comprehensively investigate the influence of phosphorus species on both the acidity and the catalytic conversion of LA to GVL. By adjusting the Zr-to-P ratios, we synthesized catalysts with enhanced acidity, achieving high conversion of LA and selectivity for GVL. The catalyst exhibited high recyclability, showing only minor deactivation over the course of five cycles. Furthermore, the catalyst was successfully applied to the one-pot conversion of furfural to GVL, showcasing its versatility in biomass conversion. This study highlights the potential of the MCM-ZrP1 catalyst for sustainable biomass conversion and offers insights for future research in renewable energy technologies.

One-pot conversion of xylose to 1,2-pentanediol catalyzed by an organic acid-assisted Pt/NC in aqueous phase.

The direct synthesis of 1,2-pentanediol (1,2-PeD) from renewable xylose and its derivatives derived from hemicellulose is appealing yet challenging due to its low selectivity for the target product. In this study, one-pot catalytic conversion of xylose to 1,2-PeD was performed by using nitrogen-doped carbon (NC) supported Pt catalysts with the assistance of organic acids. A remarkable yield of 49.3% for 1,2-PeD was achieved by reacting 0.1869 g xylose in 30 mL water at 200 °C under a hydrogen pressure of 3 MPa for 8 h in the presence of 0.1 g of 2.5Pt/NC600 catalyst and 0.1869 g propanoic acid co-catalyst. The presence of vicinal Pt-acid pair sites on the surface of the 2.5Pt/NC600 catalyst exhibited a synergistic effect in promoting the hydrogenation of furfural to furfuryl alcohol intermediate and subsequent hydrogenation and ring-opening reactions leading to the formation of 1,2-PeD. The addition of organic acids, may serve as both acid catalyst for dehydration of xylose and hydrogen donor for hydrogenation of furfural and furfuryl alcohol, thereby promoting the one-pot conversion of xylose to 1,2-PeD. Remarkably, the 2.5Pt/NC600 catalyst demonstrated outstanding catalytic performance and good reusability over five consecutive cycles without significant deactivation.

Conversion of sugars into methyl lactate over poly (ionic liquid)s functionalized Sn/beta zeolites

Methyl lactate (MLA) is a versatile high value platform chemical prepared from biomass carbohydrates, with widely application in the pharmaceutical, food, pesticide, and cosmetics. The current study presented a one-pot catalytic conversion of sugars to MLA over poly (ionic liquid)s functionalized Sn/Beta zeolites under mild conditions. The Sn/Beta zeolites were prepared by an impregnation method, followed by modification with poly (vinyl imidazole) ([PVIM]) via an in-situ free radical polymerization method. Dosages of polymer and Sn, calcination temperature, reaction temperature, catalyst amount, substrate concentration, and reaction times were optimized. Results showed that an MLA yield of 61.4 % was obtained over 3[PVIM]-Sn/Beta with complete conversion of fructose at 140 °C for 8 h. The physicochemical properties were characterized by XRD, BET, FTIR, CO-DRIFTS, NH3-TPD and pyridine-FTIR analysis, indicating the coexistence of Lewis and Brønsted acid sites. Finally, a possible reaction mechanism was proposed that the weak Lewis acidity of imidazole rings of [PVIM] effectively regulated the local microenvironment of active sites, thus promoting the interaction of the active sites with electronegative oxygens of sugars. This study can provide as a reference for the development of solid acid catalysts for the catalytic conversion of biomass to platform chemicals.

One-Pot Conversion of Starch into 5-Chloromethylfurfural and 5-Hydroxymethylfurfural in a Low-Transition Temperature Mixture

One-Pot Conversion of Starch into 5-Chloromethylfurfural and 5-Hydroxymethylfurfural in a Low-Transition Temperature Mixture

Manipulating Activity and Chemoselectivity of a Benzaldehyde Lyase for Efficient Synthesis of α-Hydroxymethyl Ketones and One-Pot Enantio-Complementary Conversion to 1,2-Diols

Manipulating Activity and Chemoselectivity of a Benzaldehyde Lyase for Efficient Synthesis of α-Hydroxymethyl Ketones and One-Pot Enantio-Complementary Conversion to 1,2-Diols

One-pot direct conversion of raw straw to furan chemicals simultaneously in a choline chloride-lactic acid/methyl isobutyl ketone biphasic system

One-pot direct conversion of raw straw to furan chemicals simultaneously in a choline chloride-lactic acid/methyl isobutyl ketone biphasic system

Sustainable production of biodiesel enabled by acid-base bifunctional ZnF2 via one-pot transformation of Koelreuteria integrifoliola oil: Process optimization, kinetics study and cost analysis

Against the backdrop of energy crisis and quest for carbon neutrality, efficient utilization of heterogeneous catalysts to facilitate one-pot conversion of low-quality nonedible oils into biodiesel, shows enormous promise for the reduction of carbon footprints and environmental pollution. In this study, an effective heterogeneous catalyst, acid-base bifunctional mesoporous ZnF2 (MP-ZnF2) was successfully fabricated for biodiesel synthesis from Koelreuteria integrifoliola oil (KIO, acid values of 8.26 mg KOH/g) via facile one-pot process. Meanwhile, systematic characterization showed the large specific surface area (62.9 m2/g), abundant mesoporous (12.15 nm), outstanding thermal stability, and plentiful stable acid-base sites (1.22 and 0.56 mmol/g) of MP-ZnF2. Consequently, MP-ZnF2 achieved a high biodiesel yield of 97.15% under moderate conditions (103 °C, 6.2 h, 10.2 wt% catalyst dosages, 29:1 MeOH/KIO molar ratio) optimized by response surface methodology (RSM). More importantly, through the kinetic investigation, a low activation energy of 49.24 kJ/mol explained the reason for its high activity, and the possible reaction mechanism of (trans)esterification was also proposed. In addition, MP-ZnF2 demonstrated satisfactory reusability (6th cycle, >90%), water resistance (8 wt% water content, 89.25%), and versatility (all yields >90%). According to cost analysis, the price of biodiesel in this work was about 0.64 $/kg. Notably, the as-prepared biodiesel conformed to ASTM D6751 and EN 14,214 standards, indicating great application prospects. It was demonstrated that one-pot transformation of KIO into biodiesel using acid-base bifunctional MP-ZnF2 contributes to the sustainable development of clean energy.

Aluminum-catalyzed direct conversion of lactones to selenolactones in the presence of elemental selenium and its application in the indium-catalyzed syntheses of dibenzyl selenides from benzyl acetates

Se-containing compounds exhibit novel chemical properties and unique pharmacological effects. Although various methods of preparing selenoesters have been reported, the synthetic focus on the related cyclic selenoesters remains insufficient. The conventional methods of synthesizing selenolactones generally involve multistep processes. In this study, an AlBr3/PhSiH3 (Ph = Phenyl) reducing system selectively catalyzed the one-pot conversion of γ-aryl-γ-lactones and elemental Se to γ-aryl-γ-selenolactones in good yields. This reducing system strongly activates elemental Se rather than elemental S. Additionally, an In(OAc)3/PhSiH3 (OAc = acetate) reducing system effectively catalyzed the direct conversion of linear benzyl acetates, which constitute substructures of lactones, and elemental Se to dibenzyl selenide derivatives.

One-pot catalytic conversion of sugars to methyl lactate over acid-base bifunctional Sn/MgO catalysts

Alkyl lactates represent such green added-value chemicals that commonly used as biodegradable green solvents, detergents, pharmaceutical intermediates et al. Catalytic conversion of carbohydrates to methyl lactate (MLA) is a representative way for high-value utilization of biomass and the key lies in the development of highly efficient catalysts. In methanol, strong acid or alkaline catalysts are usually used under high temperature and high pressure, suffering from problems such as low selectivity, high cost or contamination of environment. This study aims to develop an acid-base bifunctional heterogeneous catalyst for the one-pot conversion of sugars to MLA under mild conditions. Sn/Mg composite oxides was synthesized by a coprecipitation method and further modified by poly (vinyl imidazole) ([PVIM]) to tune the hydrophilicity. Effect of polymer and Sn amount, calcination temperature, reaction temperature, catalyst dosage, and substrate concentration were investigated. The acid-base properties were characterized by NH3-TPD, pyridine-FTIR and CO2-TPD analysis. It was found that the presence of medium acid sites and medium base sites played an important role to the cascade reactions of carbohydrates to MLA. An optimum MLA yield of 55.4% was achieved over 10[PVIM]-5Sn/MgO (0.05 g) with complete conversion of glucose (28 mM) at 140 ℃, 2 MPa N2 for 10 h. The reaction conditions are mild and no strong acid or strong base catalyst is required. Furthermore, a possible reaction mechanism was proposed that the introduction of [PVIM] effectively regulated the local microenvironment of active sites and the acid base synergism greatly promoted the retro-aldol condensation, dehydration and hydrogen transfer reactions during the conversion of glucose to MLA.

One-pot synthesis of zeolite NaX from agricultural waste for toluene removal application

One-pot conversion of rice-husk ash, which is a huge agriculture solid waste in Vietnam, to a valuable nanoporous material (zeolite FAU type X) is reported. Combined zeolite-TiO2 can be used as Adsorbent-Photocatalyst hybrid (APH) material for treatment of gaseous polluted VOCs. The combination of adsorption and photocatalyst methods in toluene treatment was investigated using TiO2-containing composites on zeolite X support which was successfully generated from one-pot synthesis method with rice husk ash from agricultural waste. The structural properties of the zeolite and the APH were examined by X-ray diffraction analysis, SEM and TGA, while the effect of hydrothermal time and temperature to the one-pot process of zeolite X synthesis was investigated. The ability to handle the toluene of this composite was also studied under humid and dry conditions at a concentration about 1000 ppmv. The results indicate the accomplishment of one-pot synthesis method in creating zeolite X materials with FAU structure and high crystallinity, along with the toluene treatment efficiency of APH materials when combined with TiO2 photocatalyst. This achievement encourages the implementation of one-pot synthesis process to create other VOCs treatment materials.