Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
12 results
Search Results
Item The hydrogen peroxide-mediated oxidation of biorenewable furfural to 2(5H)-furanone using heteropolyacids supported on ammonium y zeolite as the catalyst(Elsevier Ltd, 2020) Tiwari, R.; Bhat, N.S.; Mal, S.S.; Dutta, S.A series of heteropolyacid supported on ammonium Y zeolite (HPA-NH4YZ) catalysts were prepared and used for the catalytic oxidation of furfural to 2(5H)-furanone in aqueous hydrogen peroxide. The catalysts were characterized by PXRD, FTIR, TGA, and SEM analyses. The organic-solvent-free reaction was optimized on temperature, duration, loading of catalyst, and the equivalent of H2O2. The 20%PTA-NH4YZ catalyst showed the best catalytic activity giving 2(5H)-furanone in 40% isolated yield by solvent extraction under optimized conditions (20wt% cat., 100°C, 90min, 7.5eq. 30%H2O2). In addition, around 20% of succinic acid was recovered from the aqueous layer. © 2020 Elsevier Ltd. All rights reserved.Item Valorization of biomass-derived furfurals: reactivity patterns, synthetic strategies, and applications(Springer Science and Business Media Deutschland GmbH, 2023) Dutta, S.The expertise of synthetic organic chemistry accumulated over the past century has been instrumental in converting biomass to fuels, chemicals, and materials. Particular emphasis has been attributed to using eco-friendly reagents and reaction conditions by adhering to the principles of green chemistry. Catalysis remains at the heart of organic synthesis and has a ubiquitous presence in the organic chemistry literature. Not surprisingly, catalytic processes are increasingly used in the chemistry of renewables under commercially relevant and environmentally acceptable conditions. In this review, the synthesis of various biofuels and renewable chemicals from biomass-derived furfural and 5-(hydroxymethyl)furfural has been elaborated. Synthetic upgrading of furfurals has been shown in the light of chemical modifications of the reactive sites present in them. This review aims to provide a critical understanding of the influence of synthetic organic chemistry in biomass value addition via the furanic platform. This work will encourage the researchers to improve the existing synthetic pathways, develop new synthetic strategies, and broaden the scope of applications for biorenewable products. Graphical abstract: [Figure not available: see fulltext.]. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.Item A scalable and high-yielding synthesis of 2-(2-furyl)-1,3-dioxolane from biomass derived furfural and ethylene glycol using heteropoly acids as green catalyst(Chemical Publishing Co., 2019) Tiwari, R.; Mal, S.S.; Dutta, S.In present work, Keggin-type commercial heteropoly acids have been employed as efficient solid acid catalysts in the acetalization of biomass-derived furfural with ethylene glycol. The reaction was optimized on parameters such as the type and loading of catalyst, duration of reaction and the relative ratio of reagents. The reaction was scaled up and the cyclic acetal 2-(furan-2-yl)-1,3-dioxolane was isolated in 92 % yield within 4 h using only 2 wt % of phosphotungstic acid in refluxing benzene. © 2019 Chemical Publishing Co.. All rights reserved.Item Hydrochloric acid-catalyzed coproduction of furfural and 5-(chloromethyl)furfural assisted by a phase transfer catalyst(Elsevier Ltd, 2020) Bhat, N.S.; Vinod, N.; Onkarappa, S.B.; Dutta, S.Furfural has been produced in 53% isolated yield from D-xylose within an aqueous HCl-1,2-dichloroethane biphasic reaction mixture using benzyltributylammonium chloride (BTBAC) as a phase transfer catalyst. The use of BTBAC noticeably improved the yield of furfural compared to that in the control reaction. The reaction was optimized on the reaction temperature, duration, concentration of HCl, and the loading of BTBAC. Furfural and 5-(chloromethyl)furfural (CMF) have also been coproduced from a mixture of pentose and hexose sugars. Under optimized conditions (100 °C, 3 h, 20.2% HCl, 10 wt% BTBAC), CMF and furfural were isolated in 17% and 53% yield, respectively, from a mixture of glucose and xylose. In addition, levulinic acid was isolated from the aqueous layer in 31% yield. © 2020 Elsevier LtdItem Production of 5-(formyloxymethyl)furfural from biomass-derived sugars using mixed acid catalysts and upgrading into value-added chemicals(Elsevier Ltd, 2020) Dutta, S.In this work, 5-(formyloxymethyl)furfural (FMF) has been produced from biomass-derived hexose sugars within a biphasic reaction mixture consisting of aqueous formic acid (85%), a strong Brønsted acid catalyst, and 1,2-dichloroethane as an organic extractant. Using a combination of aqueous hydrobromic acid and formic acid, under optimized condition (80 °C, 8 h, 10 wt% substrate loading), 68% isolated yield of FMF was obtained from fructose. FMF has been demonstrated as a renewable chemical building block for the synthesis of renewable chemicals of commercial significance such as 5-methylfurfural, 2,5-diformylfuran, and 2,5-furandicarboxylic acid in good to excellent isolated yields. © 2020 Elsevier LtdItem Preparation of alkyl levulinates from biomass-derived 5-(halomethyl)furfural (X = Cl, Br), furfuryl alcohol, and angelica lactone using silica-supported perchloric acid as a heterogeneous acid catalyst(Springer Science and Business Media Deutschland GmbH, 2020) Onkarappa, S.B.; Bhat, N.S.; Dutta, S.This work reports the synthesis of a series of alkyl levulinates from biomass-derived 5-(halomethyl)furfural (X = Cl, Br), furfuryl alcohol, and angelica lactone using silica-supported perchloric acid (HClO4-SiO2) as a heterogeneous acid catalyst. The solvent-free, one-pot preparation afforded levulinate esters in excellent isolated yields (> 84%). The reactions were performed at 120 °C for 6 h in a batch-type glass pressure reactor using XMF and furfuryl alcohol in presence of excess of the alcohol reagent and 4 wt.% of the HClO4-SiO2 catalyst (0.028 mmol HClO4). Furthermore, the reaction protocol was extended for the synthesis of ALs starting with angelica lactone at 90 °C for 2 h in a round-bottomed flask by using excess alcohol and 4 wt.% of the HClO4-SiO2 catalyst. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.Item Efficient Synthesis of 5‑(Hydroxymethyl)furfural Esters from Polymeric Carbohydrates Using 5‑(Chloromethyl)furfural as a Reactive Intermediate(American Chemical Society, 2022) Bhat, N.S.; Hegde, S.L.; Dutta, S.; Sudarsanam, P.This work reports an efficient, gram-scale synthesis of 5-(hydroxymethyl)furfural (HMF) esters using biomass-derived 5-(chloromethyl)furfural (CMF) as a reactive intermediate. The HMF-esters have potential applications as chemical intermediates, fuel additives, and bioactive compounds. Initially, CMF was prepared in good yields directly from polymeric carbohydrates (starch, inulin, and cellulose) and cellulosic materials (cotton and filter paper) using a biphasic batch reaction system, consisting of aqueous hydrochloric acid and 1,2-dichloroethane. The use of ZnCl2 as an additive allowed the reaction to proceed under milder conditions while significantly improving the isolated yield of CMF. The effects of reaction temperature, reaction time, extracting solvent, and ZnCl2 loading on CMF yield were investigated. Microcrystalline cellulose was converted into CMF with a 72% isolated yield under optimized reaction conditions (80 °C, 2 h). After that, CMF was transformed into various novel esters of HMF in excellent isolated yields (>85%) by reacting with a slight excess amount of the triethylammonium salt of various alkyl/aryl carboxylic acids under solvent-free conditions. © 2022 American Chemical Society.Item Selective oxidation of biomass-derived furfural to 2(5H)-furanone using trifluoroacetic acid as the catalyst and hydrogen peroxide as a green oxidant(Springer Science and Business Media Deutschland GmbH, 2023) Bhat, N.S.; Kumar, R.; Jana, A.; Mal, S.S.; Dutta, S.In this work, biomass-derived furfural has been selectively oxidized to 2(5H)-furanone using aqueous hydrogen peroxide as the green oxidant. Among various homogeneous acid catalysts screened for the transformation, trifluoroacetic acid (TFA) was found to be the most suitable candidate that afforded up to 52% isolated yield of 2(5H)-furanone under mild conditions (RT, 1 h). In addition, succinic acid was recovered in nearly 20% yield from the aqueous layer. The organic solvent-free, gram-scale reaction was optimized on temperature, the molar ratio of H2O2 and furfural, and the amount of TFA used. [Figure not available: see fulltext.]. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.Item Renewable synthesis of novel acrylates from biomass-derived 5-substituted-2-furaldehydes by Morita-Baylis-Hillman reaction(John Wiley and Sons Inc, 2023) Anchan, H.N.; Dutta, S.Biomass-derived furfurals are becoming increasingly popular as renewable chemical building blocks for synthesizing specialty chemicals. Morita-Baylis-Hillman (MBH) reaction is a classic carbon-carbon bond-forming transformation between the α-position of an activated alkene and a carbon electrophile (e. g., aldehyde) using a nucleophilic catalyst, such as a tertiary amine or phosphine. The MBH reaction is highly atom economical, affords excellent yields of adducts under mild reaction conditions, introduces substantial molecular complexity, and enjoys broad substrate scope. In this work, several novel MBH adducts have been synthesized starting from biomass-derived 5-substituted-2-furaldehydes and acrylates using 1,4-diazabicyclo[2.2.2]octane (DABCO) as the organocatalyst. This work reports the first systematic study of the MBH reaction of 5-substituted-2-furaldehydes and acrylates. A general synthetic protocol for the high-yielding synthesis of MBH adducts has been developed. The reactions were performed at room temperature under solvent-free conditions, and the spectroscopically pure products were produced in good to excellent isolated yields. Moreover, DABCO was recovered from the reaction mixture and successfully recycled. © 2023 Wiley-VCH GmbH.Item Efficient preparation of hybrid biofuels from biomass-derived 5-(acetoxymethyl)furfural and petroleum-derived aromatic hydrocarbons(Royal Society of Chemistry, 2024) Yadav, A.K.; Bhat, N.S.; Kaushik, S.; Seikh, A.H.; Dutta, S.Fuel candidates containing both petroleum-derived and biomass-derived molecules in their structural motifs ensure both feedstocks are used optimally and coherently. This work reports a straightforward and efficient preparation of 5-(arylmethyl)furfurals (AMFFs), 2-(arylmethyl)furans (AMFs), and 2-(arylmethyl)-5-methylfurans (AMMFs) as hybrid biofuels (or fuel oxygenates) starting from carbohydrate-derived 5-(acetoxymethyl)furfural (AcMF) and petroleum-derived aromatic hydrocarbons. The AMFFs were prepared by Friedel-Crafts reaction between AcMF and aromatic hydrocarbons (e.g., BTX, mesitylene) by employing anhydrous ZnCl2 as the catalyst. AMFs were prepared by decarbonylation of AMFFs over the Pd(OAc)2 catalyst under solvent-free conditions. In contrast, AMMFs were produced by hydrogenating AMFFs in methanol using gaseous hydrogen and the 10% Pd/C catalyst. The catalytic transformations were optimized on various parameters, and all the biofuel candidates were obtained in good to excellent isolated yields (>80%) under moderate conditions. © 2024 The Royal Society of Chemistry.