A5042152864- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Lignin and Wood Chemistry
- Oxidative Organic Chemistry Reactions
- Catalysis for Biomass Conversion
- Fluorine in Organic Chemistry
- Radical Photochemical Reactions
- Mesoporous Materials and Catalysis
- Phytochemicals and Antioxidant Activities
- Chemical Synthesis and Analysis
- Nanocomposite Films for Food Packaging
- Catalytic Cross-Coupling Reactions
- Synthetic Organic Chemistry Methods
- DNA and Nucleic Acid Chemistry
- Antifungal resistance and susceptibility
- Carbohydrate Chemistry and Synthesis
- Chemical Reaction Mechanisms
- Pneumocystis jirovecii pneumonia detection and treatment
- Biofuel production and bioconversion
- Advanced Cellulose Research Studies
- Asymmetric Hydrogenation and Catalysis
- Sulfur-Based Synthesis Techniques
- Catalytic C–H Functionalization Methods
- Material Properties and Processing
- Catalysis and Hydrodesulfurization Studies
University of Helsinki
2010-2020
University of Amsterdam
2007-2011
We describe herein an efficient microwave-assisted aqueous biphasic dehydration of carbohydrates to 5-hydroxymethylfurfural (HMF).
Abstract The effect of salts and Brønsted acids on the Lewis acid (CrCl 3 ⋅ 6 H 2 O)‐catalyzed glucose dehydration to 5‐hydroxymethylfurfural (HMF) in aqueous media are described. We show that reaction with bromide place chlorides leads higher HMF yields. influence can be attributed anions solution, specifically enhancing fructose step. Additionally, we demonstrate kinetics governed strongly by acidity. Although step is accelerated addition acids, even a catalytic scale, significant...
Abstract Lignin, esterified with palmitic and lauric acid chloride, has been studied for the application as coating on fiber-based packaging material. The aim was to improve barrier properties against water vapor oxygen of paperboard. esterification followed by Fourier transform infrared spectroscopy, 31 P nuclear magnetic resonance gel permeation chromatography measurements. lignin esters were applied paperboard formed a continuous film. moisture property coated paperboards characterized...
Naturally occurring hydroxycinnamic acids, such as ferulic and sinapic are known to possess antioxidant activity. In this study, acid were covalently attached oat spelt arabinoxylan birch wood glucuronoxylan by esterification in a two-step feasible synthesis generate modified xylans with various degrees of substitution. The obtained derivatives fully analyzed FT-IR, NMR, HPSEC experiments confirm the degree antioxidative potential conjugates was evaluated using emulsion lipid oxidation test....
Abstract A method for aerobic alcohol oxidation catalysed by Fe(NO 3 ) /2,2’‐bipyridine/TEMPO has allowed highly selective conversion of primary alcohols into either aldehydes or carboxylic acids in one‐step. The proceeded selectively to aldehydes, as TEMPO was present the reaction. Nevertheless, were further oxidized reaction time extended. Detailed investigation suggested, that deoxygenation TMP enabled auto‐oxidation acids, which initially inhibited presence TEMPO. procedure also...
Abstract 5‐Hydroxymethylfurfural (HMF) is a pivotal chemical in the utilization of biomass as feedstock. For this approach vast majority methods require access to pure HMF from before its utilization, which incorporates one or more purification steps that obstruct industrial implementation. We describe an operationally simple and versatile method encompasses both dehydration several carbohydrate substrates into subsequently direct conversion various high value‐added furan derivatives one‐pot...
Abstract This report describes intramolecular [2+2] photocycloadditions of several butenolides with an allenylmethyl substituent at the 5‐position. These photosubstrates were prepared from 2‐(silyloxy)furans through silver‐mediated reactions bromides. Two cases studied where lactone was replaced by N ‐Boc‐lactam. Irradiations carried out 300 nm UV‐light in acetonitrile/acetone mixtures. Crossed cycloadducts produced good yields via cycloaddition heterocyclic double bond allene internal bond....
Abstract The [2+2] photocycloaddition of allenes 15 – 18 , 23 and 26 was studied. Irradiation a solution these substrates in acetonitrile at 300 nm resulted the clean conversion starting materials into mixture photoproducts. major product all cases bicyclic pyrrole or furan fused to an eight membered ring (43–70 % yield). formation products is thought be result heteroatom‐induced fragmentation straight adduct ( 7 ). This supported by irradiation carbon analogue 32 which allowed isolation 45...
N-aryl-oxazolidinones is a prominent family of antimicrobials used for treating infections caused by clinically prevalent Gram-positive bacteria. Recently, boron-containing compounds have displayed intriguing potential in the antibiotic discovery setting. Herein, we report unprecedented introduction moiety such as an aryl boronic acid external region oxazolidinone structure via chemoselective acyl coupling reaction. As result, accessed series analogues with distal pharmacophore on scaffold....
This report describes an efficient procedure for the generation and isolation of various thymine thymidine 5,6-epoxides from corresponding trans-5,6-bromohydrins by reaction with triethylamine. The quantitative epoxides, accomplished solvent precipitation triethylamine hydrobromide, enabled their regiospecific ring-opening at C6 position organometallic nucleophiles. was amenable to a broad range alkyl, aryl, alkenyl, alkynyl organomagnesium, -zinc, -aluminum, or -boron reagents, although...
C-6-substituted thymidines are biochemically important compounds. The thymidine (6–4) photoproduct [i.e., 5-hydroxy-6-(thymidine-4-yl) dihydrothymidine], in particular, is a DNA lesion that triggered by the UV irradiation of sunlight. Herein, we report metal-free cis-diastereoselective ring opening 5,6-epoxides using mildly nucleophilic organofluoroborates presence BF3·Et2O to provide facile access analogues. A broad range aryl and alkynylfluoroborates compatible with reaction conditions,...
The Crabbé homologation of polymer-supported propargylamine with paraformaldehyde, CuI, and dicyclohexylamine in 1,4-dioxane at 100 °C, followed by cleavage dilute trifluoroacetic acid, furnishes N-(buta-2,3-dien-1-yl)amides as isolable products. N-acyltriazene linker on Merrifield resin serves simultaneously a protecting group for the nucleophilic primary amine. product diversity is achieved altering acyl chloride acylation triazene linker. In addition to being new route nitrogen-containing...
Abstract The formation of thymine and thymidine 5,6‐epoxides from the corresponding trans‐5,6‐bromohydrins their in‐situ reaction with a broad range organometallic reagents is examined.