scholarly journals Effective Degradation of Cellulose by Microwave Irradiation in Alkaline Solution

2021 ◽  
Author(s):  
Lama Jabareen ◽  
Moorthy Maruthapandi ◽  
Arumugam Saravanan ◽  
Aharon Gedanken
Keyword(s):  
Lignocellulosic Biomass ◽  
Crystalline Cellulose ◽  
Reaction Products ◽  
Reaction Conditions ◽  
One Pot ◽  
Platform Chemicals ◽  
Subsequent Step ◽  
Novel Method ◽  
Main Component ◽  
C Nmr

Abstract The utilization of lignocellulosic biomass is effective to produce chemicals and fuels, which are of importance for the establishment of a sustainable society. The conversion of cellulose, which is the main component of the lignocellulosic biomass, into significant chemicals that can be further converted to different chemicals or fuels in the subsequent step, under gentle conditions is a promising route. Organic acids such as acetic acid, glycolic acid and formic acid are significant chemicals are examples of such products. A novel method to producing important platform chemicals from Micro-crystalline cellulose was developed. Micro-crystalline cellulose was degraded as a result of an oxidation with potassium chlorate by microwave radiation, in a one-pot procedure, efficient reaction conditions such as short reaction time and full conversion of the cellulose were identified. The reaction products have been analyzed by 1H, 13C NMR, XPS, TGA and XRD.

scholarly journals Heterogeneous acidic catalysts for the tetrahydropyranylation of alcohols and phenols in green ethereal solvents

2018 ◽  
Vol 14 ◽  
pp. 1655-1659 ◽  
Author(s):  
Ugo Azzena ◽  
Massimo Carraro ◽  
Gloria Modugno ◽  
Luisa Pisano ◽  
Luigi Urtis
Keyword(s):  
Organic Chemistry ◽  
Heterogeneous Catalysis ◽  
Important Class ◽  
Green Solvents ◽  
Reaction Products ◽  
Reaction Conditions ◽  
One Pot ◽  
Acidic Catalysts ◽  
Set Up ◽  
Work Up

The application of heterogeneous catalysis and green solvents to the set up of widely employed reactions is a challenge in contemporary organic chemistry. We applied such an approach to the synthesis and further conversion of tetrahydropyranyl ethers, an important class of compounds widely employed in multistep syntheses. Several alcohols and phenols were almost quantitatively converted into the corresponding tetrahydropyranyl ethers in cyclopentyl methyl ether or 2-methyltetrahydrofuran employing NH4HSO4 supported on SiO2 as a recyclable acidic catalyst. Easy work up of the reaction mixtures and the versatility of the solvents allowed further conversion of the reaction products under one-pot reaction conditions.

Synthesis and Characterization of Substituted μ-oxo-bis[tetra-phenylporphyrinatoiron] Compounds

2015 ◽  
Vol 748 ◽  
pp. 183-186
Author(s):  
Zhi Cheng Sun ◽  
Shu Ying Chen ◽  
Zhi Peng Guo ◽  
Mei Juan Cao ◽  
Lu Hai Li
Keyword(s):  
Infrared Spectra ◽  
Elemental Analysis ◽  
Aromatic Aldehydes ◽  
Synthesis And Characterization ◽  
Visible Spectroscopy ◽  
Reaction Conditions ◽  
One Pot ◽  
Optimum Reaction ◽  
Novel Method

A novel one-pot method for the synthesis of substituted μ-oxo-bis [tetraphenyl porphyrinatoiron] compounds ([TRPPFe]2O) from pyrrole and aromatic aldehydes was proposed and investigated in this paper. Four kinds of [TRPPFe]2O were designed and synthesized by one-pot reaction and characterized by elemental analysis, infrared spectra and ultraviolet-visible spectroscopy. Moreover, the [TRPPFe]2O yields of 18.7~22.4% could be obtained with this novel method under the optimum reaction conditions.

scholarly journals Microwave Assisted Three Component Reaction Conditions to Obtain New Thiazolidinones with Different Heterocyclic Skeletons

Proceedings ◽  
2019 ◽  
Vol 41 (1) ◽  
pp. 38
Author(s):  
Fernando J. Lorenzo ◽  
Romina A. Ocampo ◽  
Sandra D. Mandolesi
Keyword(s):  
Microwave Irradiation ◽  
Thioglycolic Acid ◽  
Aldehyde Group ◽  
Green Solvent ◽  
Reaction Products ◽  
Reaction Conditions ◽  
One Pot ◽  
Microwave Assisted ◽  
Three Component Reaction ◽  
The One

We present here a new proposal for the “one pot” generation of new 4-thiazolidinones (9a–e) through a multicomponent reaction under microwave irradiation conditions, using aromatic and heteroaromatic amines (8a–e), absolute ethanol as a “green” solvent and modifying the aldehyde group in the glycosidic residue, synthesized from D-mannitol. The study is focused in the variation of the irradiation times and the concentration of thioglycolic acid in order to study the possibility of controlling the structure and/or stereochemistry of the products formed in the reaction. Thiazolidinones 9a–d were obtained with a 69–82% The generation of the corresponding reaction products were monitored by TLC and CG-MS, taking reaction aliquots. The conditions reaction proved to be chemoselective depending on the excess of acid and irradiation times.

Oxidation of triamantane by sulphuric acid

1983 ◽  
Vol 48 (4) ◽  
pp. 1074-1076 ◽  
Author(s):  
Zdeněk Kafka ◽  
Luděk Vodička ◽  
Milan Hájek
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Sulphuric Acid ◽  
Functional Groups ◽  
Reaction Products ◽  
Reaction Conditions ◽  
Nmr Spectrometry ◽  
C Nmr

The oxidation of triamantane by sulphuric acid was studied in various reaction conditions. 8-Triamantanone, 8,16-triamantanedione, and 15-hydroxy-8-triamantanone were isolated and identified as reaction products. The reaction was monitored and the purity of the compounds prepared was checked by gas chromatography and mass spectrometry, the position of the functional groups was determined by 13C NMR spectrometry.

scholarly journals A Facile and Catalyst-free Synthesis of Hexahydroacridine-1,8(2H,5H )-dione and Octahydroacridin-10(1H )-yl)thiourea Derivatives: Inter- and Intramolecular Aza-Michael addition

2020 ◽  
Vol 26 (1) ◽  
pp. 26-32 ◽  
Author(s):  
Nader Noroozi Pesyan ◽  
Narmin Akhteh ◽  
Hana Batmani ◽  
Barış Anıl ◽  
Ertan Şahin
Keyword(s):  
Hydroxylamine Hydrochloride ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
One Pot ◽  
Thiourea Derivatives ◽  
H Nmr ◽  
Nmr Spectrometry ◽  
The One ◽  
Convenient Technique ◽  
C Nmr

AbstractAn easy and convenient technique for the one-pot synthesis of novel compounds of hexahydroacridine-1,8(2H,5H)-dione and octahydroacridin-10(1H)-yl) thiourea derivatives has been developed by the reaction of the octahydro-1H-xanthenes with hydroxylamine hydrochloride and thiosemicarbazide in ethylene glycol, which is a green solvent, under mild reaction conditions. IR, 1H NMR, 13C NMR spectrometry, and X-ray diffraction analysis were used to identify the structures of these compounds.

scholarly journals Analysis of bilirubin and bilirubin mono- and di-conjugates. Determination of their relative amounts in biological samples

1980 ◽  
Vol 185 (1) ◽  
pp. 115-128 ◽  
Author(s):  
N Blanckaert
Keyword(s):  
Biological Samples ◽  
Methyl Esters ◽  
Dimethyl Ester ◽  
Crystalline Form ◽  
Reaction Products ◽  
Reaction Conditions ◽  
Normal Rat ◽  
Novel Method ◽  
Rat Bile

1. A novel method for determination of the relative amounts of unconjugated bilirubin and sugar mono- and di-conjugates of bilirubin in biological samples, including serum, is described and illustrated by its application to the analysis of bilinoids in rat bile. 2. The method is based on specific conversion of the carbohydrate conjugates of bilirubin into the corresponding mono- or di-methyl esters by base-catalysed transesterification in methanol. Under the selected reaction conditions, unconjugated biliru-in remains intact and no dipyrrole exchange in the bilinoids is detectable; transesterification of bilirubin mono- or di-glucuronide is virtually complete (approx. 99%), and sponification is negligible (less than 1%); recovery of the pigments is approx. 95%. 3. The reaction products bilirubin and its methyl esters are separated by t.l.c. and determined spectrophotometrically; the two isomeric bilirubin-IX alpha monomethyl esters are separated and therefore can be determined individually. 4. Reference bilirubin mono- and di-methyl esters have been synthesized and characterized, and the two isomers of bilirubin-IX alpha monomethyl ester and bilirubin dimethyl ester were obtained individually, in crystalline form. 5. With this new method, virtually all bilinoids (over 99%) in normal rat bile have been found to be conjugated, with diconjugates (71%) predominating. A significantly increased proportion of monoconjugates is present in bile collected from heterozygous Gunn rats or from normal rats that were refused with large amounts of bilirubin.

One-Pot Synthesis of Functionalised 4-Spiro-1,4-Dihydropyridines Via [1+2+1+2]-Cyclisation

2017 ◽  
Vol 41 (9) ◽  
pp. 513-516 ◽  
Author(s):  
Pan Zhou ◽  
Biao Hu ◽  
Lingling Lu ◽  
Rong Huang ◽  
Fuchao Yu
Keyword(s):  
Acetic Acid ◽  
Ammonium Acetate ◽  
Water Solution ◽  
Reaction Conditions ◽  
One Pot ◽  
Efficient Approach ◽  
H Nmr ◽  
Three Component Reaction ◽  
C Nmr ◽  
Operational Simplicity

A simple and efficient approach for the synthesis of 4-spiro-1,4-DHP derivatives has been developed, involving one-pot three-component reaction of isatins, N,N-dimethylenaminones with ammonium acetate in EtOH–water solution promoted by acetic acid. Compared with the previous [1+2+3]-cyclisation method, this [1+2+1+2]-cyclisation procedure has advantages as it is more environmentally friendly, has easier operational simplicity, and requires milder reaction conditions. Moreover, these novel compounds have been obtained in moderate to good yields and their structures have been confirmed by 1H NMR, 13C NMR and IR and HRMS spectroscopy.

scholarly journals Para toluenesulfonic acid-catalyzed one-pot, three-component synthesis of benzo[5,6]chromeno[3,2-c]quinoline compounds in aqueous medium

2021 ◽  
Vol 27 (1) ◽  
pp. 90-99
Author(s):  
Naser Sadeghpour Orang ◽  
Hadi Soltani ◽  
Mehdi Ghiamirad ◽  
Mehdi Ahmadi Sabegh
Keyword(s):  
Thermal Conditions ◽  
Reaction Conditions ◽  
One Pot ◽  
Mass Spectral ◽  
H Nmr ◽  
Toluenesulfonic Acid ◽  
Ft Ir ◽  
High Yields ◽  
Arylglyoxal Monohydrates ◽  
C Nmr

Abstract A new series of benzo[5,6]chromeno[3,2-c]quinoline derivatives were successfully synthesized using various arylglyoxal monohydrates, quinoline-2,4-dione, and β-naphthol in H2O:EtOH (2:1) as a green solvent in the presence of catalytic amounts p-toluenesulfonic acid as a mild catalyst under reflux conditions with high yields (83–92%). The reaction conditions were optimized in different solvents at variable thermal conditions, and the optimized reaction condition for this synthesis has been reported. The structures of all new products were defined by 1H-NMR, 13C-NMR, FT-IR, mass spectral data, and HRMS.

scholarly journals Chemocatalytic Conversion of Cellulose into Key Platform Chemicals

2018 ◽  
Vol 2018 ◽  
pp. 1-21 ◽  
Author(s):  
Guangbi Li ◽  
Wei Liu ◽  
Chenliang Ye ◽  
Xiaoyun Li ◽  
Chuan-Ling Si
Keyword(s):  
Heterogeneous Catalysis ◽  
Lignocellulosic Biomass ◽  
Heterogeneous Catalysts ◽  
Value Added ◽  
Direct Conversion ◽  
Reaction Conditions ◽  
Platform Chemicals ◽  
Stable Chemical ◽  
Wide Range ◽  
Sustainable Societies

Chemocatalytic transformation of lignocellulosic biomass to value-added chemicals has attracted global interest in order to build up sustainable societies. Cellulose, the first most abundant constituent of lignocellulosic biomass, has received extensive attention for its comprehensive utilization of resource, such as its catalytic conversion into high value-added chemicals and fuels (e.g., HMF, DMF, and isosorbide). However, the low reactivity of cellulose has prevented its use in chemical industry due to stable chemical structure and poor solubility in common solvents over the cellulose. Recently, homogeneous or heterogeneous catalysis for the conversion of cellulose has been expected to overcome this issue, because various types of pretreatment and homogeneous or heterogeneous catalysts can be designed and applied in a wide range of reaction conditions. In this review, we show the present situation and perspective of homogeneous or heterogeneous catalysis for the direct conversion of cellulose into useful platform chemicals.

Michael-Michael Aldol Reaction of Chalcones with Cyanoacetylurea and Cyanoacetylpiperidine

1995 ◽  
Vol 60 (4) ◽  
pp. 594-604 ◽  
Author(s):  
Hani D. Tabba ◽  
Nidal M. Yousef ◽  
Mohammad M. Al-Arab
Keyword(s):  
Room Temperature ◽  
Reaction Products ◽  
One Pot ◽  
X Ray ◽  
X Ray Crystallography ◽  
Anhydrous Alcohol ◽  
One Pot Condensation ◽  
The One ◽  
Sodium Alkoxide ◽  
C Nmr

Several highly substituted cyclohexane derivatives were synthesized by the one-pot condensation of chalcones and cyanoacetylurea (2 : 1) using sodium alkoxide in anhydrous alcohol at room temperature. The structure of the reaction products was established by infrared, 1H and 13C NMR spectroscopy as well as by their elemental analysis. Single crystal X-ray crystallography shows the presence of the cyclohexane moiety.

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