Regiochemical control in the addition of aryl N-sulphinylamines to juglone and juglone derivatives

961-96

Acidic Ionic Liquids

Ionic liquid with acidic properties is an important branch in the wide ionic liquid field and the aim of this article is to cover all aspects of these acidic ionic liquids, especially focusing on the developments in the last four years. The structural diversity and synthesis of acidic ionic liquids are discussed in the introduction sections of this review. In addition, an unambiguous classification system for various types of acidic ionic liquids is presented in the introduction. The physical properties including acidity, thermo-physical properties, ionic conductivity, spectroscopy, and computational studies on acidic ionic liquids are covered in the next sections. The final section provides a comprehensive review on applications of acidic ionic liquids in a wide array of fields including catalysis, CO2 fixation, ionogel, electrolyte, fuel-cell, membrane, biomass processing, biodiesel synthesis, desulfurization of gasoline/diesel, metal processing, and metal electrodeposition

Ionic Liquids in Biomass Processing

The ionic liquids have emerged as new solvents and catalysts for processing biomass to value added chemicals and fuels. This review will present the recent developments in applications of ionic liquids in lignocellulosic biomass pretreatments, depolymerization, biodiesel synthesis, dehydration of carbohydrates to renewable feedstock chemicals as well as further transformations of biomass derived feedstocks such as furfural, 5-hydroxymethylfurfural and levulinic acid to value added chemicals. In addition, the recycling of ionic liquids used in biomass processing is also discussed in the review

5-Hydroxymethylfurfural Based Polymers

5-Hydroxymethylfurfural (HMF) is a renewable resource based potentialplatform chemical useful in the synthesis of polymers. This versatilesix carbon furan system with primary alcohol and aldehyde groups canbe prepared from the triple dehydration of hexoses, which are producedfrom depolymerization of the major cellulosic fraction of abundant lignocellulosicbiomass. A verity of monomers suitable for polymer synthesiscan be prepared from HMF by adjusting the oxidation states of the functionalgroups and simple derivatization methods. Some of the well studiedderivatives of HMF includes; 2/5-bis(formyl)furan/ 2,5-furandicarboxylicacid, 2,5-furandicarboxylicacid dichloride, 2,5-bis(hydroxymethyl)furan,2,5-bis(aminomethyl)furan, furanic diesters and furanic diisocyanates.Recent progress in the synthesis, characterization, and physical propertiesstudies of the poly-Schiff-base, polyester, polyamide, polyurethane, polybenzoimidazole,and polyoxadiazole type furanic polymers from theseHMF derived monomers will be discussed in this chapter.© 2012 Scrivener Publishing LLC

Nitrosation of β′-hydroxylamino-α,β-unsaturated oximes: Synthesis of 1,7-dioxa-2,6-diaza-spiro[4,4]nona-2,8-diene ring system

Nitrosation of bis arylidene acetone oximes with nitrous acid in glacial acetic acid gives 3-vinyl pyrazolone-N,N′-dioxides in 32-37% yield. Similar reactions of 2-arylidene-6-(hydroxylamino-aryl-methyl)-cyclohexanone oximes give tricyclic compounds with dioxa-2,6-diaza-spiro[4,4]nona-2,8-diene ring systems in 77-84% yield. © 2005 Elsevier Ltd. All rights reserved

A new synthesis of quinoline-5,8-quinone

Sensitised photo-oxidations of 8-hydroxy quinoline (1) or 5-hydroxy quinoline (2) gives quinoline-5,8-quinone (3) in 64-70% yield

Handbook of Cellulosic Ethanol

Comprehensive coverage on the growing science and technology of producing ethanol from the world\u27s abundant cellulosic biomass. The inevitable decline in petroleum reserves and its impact on gasoline prices, combined with climate change concerns, have contributed to current interest in renewable fuels. Bioethanol is the most successful renewable transport fuel-with corn and sugarcane ethanol currently in wide use as blend-in fuels in the United States, Brazil, and a few other countries. However, there are a number of major drawbacks in these first-generation biofuels, such as their effect on food prices, net energy balance, and poor greenhouse gas mitigation. Alternatively, cellulosic ethanol can be produced from abundant lignocellulosic biomass forms such as agricultural or municipal wastes, forest residues, fast growing trees, or grasses grown in marginal lands, and should be producible in substantial amounts to meet growing global energy demand. The Handbook of Cellulosic Ethanol covers all aspects of this new and vital alternative fuel source, providing readers with the background, scientific theory, and recent research progress in producing cellulosic ethanol via different biochemical routes, as well as future directions. The seventeen chapters include information on: Advantages of cellulosic ethanol over first-generation ethanol as a transportation fuel; Various biomass feedstocks that can be used to make cellulosic ethanol; Details of the aqueous phase or cellulolysis route, pretreatment, enzyme or acid saccharification, fermentation, simultaneous saccharification fermentation, consolidated bioprocessing, genetically modified microorganisms, and yeasts; Details of the syngas fermentation or thermochemical route, gasifiers, syngas cleaning, microorganisms for syngas fermentation, and chemical catalysts for syngas-to-ethanol conversion; Distillation and dehydration to fuel-grade ethanol; Techno-economical aspects and the future of cellulosic ethanol; Readership: Chemical engineers, chemists, and technicians working on renewable energy and fuels in industry, research institutions, and universities. The Handbook can also be used by students interested in biofuels and renewable energy issues

Acidic Ionic Liquid Catalyzed One-Pot Conversion of Cellulose to Ethyl Levulinate and Levulinic Acid in Ethanol-Water Solvent System

Cellulose can be converted to a mixture of ethyl levulinate and levulinic acid by heating with a Brönsted acidic ionic liquid catalyst in aqueous ethanol medium in a one-pot operation under mild conditions. The highest ethyl levulinate yield of 19.0 % was obtained for a reaction carried out at 170 °C for 12 h in water-ethanol medium containing 38.5 % water and using 1-(1-propylsulfonic)-3-methylimidazolium chloride as the catalyst. The levulinic acid yields continue to increase with increasing water content up to about 54 % water in aqueous ethanol for reactions carried out at 150 °C for 48 h, and the highest levulinic acid yield was 23.7 %. The acidic, ionic liquid catalyst used can be efficiently recovered (96 %) from the water phase with negligible contamination, and the stability of the catalyst was confirmed by comparison of the 1H NMR spectrum of the recovered catalyst with fresh catalyst

Synthesis of a silica-immobilized Brönsted acidic ionic liquid catalyst and hydrolysis of cellulose in water under mild conditions

A silica immobilized imidazolium-type acidic ionic liquid catalyst was shown to be a better catalyst than n-propylsulfonic acid silica (PrSO 3H-SiO2) and sulfonic acid silica (SO3H- SiO2) for the hydrolysis of untreated Sigmacell Cellulose (DP ~ 450) in water. For example, new catalyst produced the highest TRS yield of 48.1% after 3 h at 190 C, whereas cellulose samples heated with PrSO 3H-SiO2 and SO3H-SiO2 catalysts produced only 19.9% and 13.2% TRS yields, respectively, under identical conditions. The new catalyst could be recycled up to four cycles with a small loss in catalytic activity. © 2014 Elsevier B.V

Studies of planar poly(3,4-disubstituted-thiophenes)

Ab initio calculations on bithiophenes, confirmed by X-ray analysis, show how to design polythiophenes with C=O groups in both the 3- and 4-positions which are completely planar. Planarity results from coulombic attraction between a carbonyl O and a nearby S. A model bithiophene and two polythiophene imides which are potentially completely planar have been prepared and studied. © 2003 Elsevier Science B.V. All rights reserved