Tag: M.W=100-150

Onkarappa, Sharath Bandibairanahalli published the artcileEfficient and Scalable Production of Alkyl Levulinates from Cellulose-Derived Levulinic Acid Using Heteropolyacid Catalysts, Related Products of esters-buliding-blocks, the main research area is levulinic acid heteropolyacid catalyst esterification alkyl levulinate preparation.

This work reports a straightforward and scalable synthesis of a series of alkyl levulinates from cellulose-derived levulinic acid and alkyl alcs. using com. available heteropolyacid catalysts under homegenous conditions. The reaction was optimized on parameters such as temperature, molar ratio of reagents, type and loading of catalyst. The solvent-free reactions afforded alkyl levulinates in high isolated yields (>85%) using only slight excess of alcs. and 10 wt% of catalyst at 120 °C in 6 h. Further, the catalysts were successfully recycled for three consecutive cycles without significant loss in activity.

ChemistrySelect published new progress about Aliphatic esters Role: IMF (Industrial Manufacture), PREP (Preparation). 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Related Products of esters-buliding-blocks.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Kurisingal, Jintu Francis published the artcileWater-Tolerant DUT-Series Metal-Organic Frameworks: A Theoretical-Experimental Study for the Chemical Fixation of CO2 and Catalytic Transfer Hydrogenation of Ethyl Levulinate to γ-Valerolactone, HPLC of Formula: 539-88-8, the main research area is zirconium hafnium naphthalenedicarboxylate Dresden University MOF preparation catalyst; water tolerant DUT MOF preparation fixation carbon dioxide catalysis; transfer hydrogenation MOF catalyzed ethyl levulinate gamma valerolactone preparation; cycloaddition carbon dioxide epoxide zirconium hafnium naphthalenedicarboxylate MOF catalyzed; CO2; DUT; biomass; cyclic carbonate; γ-valerolactone.

A series of highly thermally and hydrolytically stable porous solids with intriguing properties of zirconium- and hafnium-based metal-organic frameworks (MOFs) [Dresden University of Technol. (DUT) series] was synthesized. The DUT MOFs were effective catalysts for both epoxide-CO2 cycloaddition reactions and the catalytic transfer hydrogenation (CTH) of Et levulinate (EL). In particular, 12-connected DUT-52(Zr) showed higher catalytic activity than eight- and six-connected catalysts in the synthesis of cyclic carbonates as well as in the production of γ-valerolactone (GVL). The secondary building unit connectivity, coexistence of a moderate number of acidic and basic sites, Brunauer-Emmett-Teller surface area, and combined effects of the pores of the MOFs seem to influence the catalytic activity. The reaction mechanism for the DUT-52(Zr)-mediated cycloaddition reaction of CO2 and the CTH reactions were investigated in detail by using periodic d. functional theory calculations To the best of authors knowledge, this is the first detailed computational study for the formation of GVL from EL by using MOF as the catalyst. In addition, grand canonical Monte Carlo simulations predicted the strong interaction of CO2 mols. with the DUT-52(Zr) framework. Remarkably, the DUT-series catalysts possess extraordinary tolerance toward water. Further, DUT-52(Zr) is recyclable and is an efficient catalyst for cycloaddition and CTH reactions for at least five uses without obvious reductions in the activity or structural integrity.

ACS Applied Materials & Interfaces published new progress about Cyclic carbonates Role: SPN (Synthetic Preparation), PREP (Preparation). 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, HPLC of Formula: 539-88-8.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Jiang, Haiwei published the artcileHydrothermal liquefaction of Cd-enriched Amaranthus hypochondriacus L. in ethanol-water co-solvent: Focus on low-N bio-oil and heavy metal/metal-like distribution, HPLC of Formula: 623-50-7, the main research area is hydrothermal liquefaction cadmium amaranthus hypochondriacus; ethanol water nitrogen bio oil heavy metal.

The high nitrogen content in bio-oil from protein-rich biomass will cause the possible pollution problems by NOX emissions during combustion. In this study, Cd-enriched Amaranthus hypochondriacus L. (AHL) was treated by hydrothermal liquefaction (HTL) in ethanol-water co-solvent aiming to reduce the nitrogen content of the bio-oil. Besides, aqueous phase recycling (APR) was applied to achieve a higher bio-oil yield. HTL in ethanol-water co-solvent with APR three times resulted in the maximum bio-oil yield (47.26%) and greatly reduced the nitrogenous compounds content of bio-oil. During the APR process, the increase of total nitrogen (TN) content in the aqueous phase indicated that organic-N in the organic phase transformed into NH+4 to the aqueous phase. Acetic acid (13.87-22.37 mg/mL) was dominated in the aqueous phase, leading to a low pH value (6.27-5.29), which could serve as the possible catalyst for the HTL process during APR that can be the reason for the higher bio-oil yield. After the HTL process, Cr, Cu, Cd and Pb remained mostly in bio-char while As was present largely in the aqueous phase. Thus, this study demonstrated that the APR for HTL process in ethanol-water co-solvent can be a hopeful method to dispose the high-protein biomass for improved bio-oil yield and quality.

Fuel published new progress about Alcohols Role: TEM (Technical or Engineered Material Use), USES (Uses). 623-50-7 belongs to class esters-buliding-blocks, name is Ethyl 2-hydroxyacetate, and the molecular formula is C4H8O3, HPLC of Formula: 623-50-7.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Jiang, Haiwei published the artcileHydrothermal liquefaction of Cd-enriched Amaranthus hypochondriacus L. in ethanol-water co-solvent: Focus on low-N bio-oil and heavy metal/metal-like distribution, Product Details of C7H12O3, the main research area is hydrothermal liquefaction cadmium amaranthus hypochondriacus; ethanol water nitrogen bio oil heavy metal.

The high nitrogen content in bio-oil from protein-rich biomass will cause the possible pollution problems by NOX emissions during combustion. In this study, Cd-enriched Amaranthus hypochondriacus L. (AHL) was treated by hydrothermal liquefaction (HTL) in ethanol-water co-solvent aiming to reduce the nitrogen content of the bio-oil. Besides, aqueous phase recycling (APR) was applied to achieve a higher bio-oil yield. HTL in ethanol-water co-solvent with APR three times resulted in the maximum bio-oil yield (47.26%) and greatly reduced the nitrogenous compounds content of bio-oil. During the APR process, the increase of total nitrogen (TN) content in the aqueous phase indicated that organic-N in the organic phase transformed into NH+4 to the aqueous phase. Acetic acid (13.87-22.37 mg/mL) was dominated in the aqueous phase, leading to a low pH value (6.27-5.29), which could serve as the possible catalyst for the HTL process during APR that can be the reason for the higher bio-oil yield. After the HTL process, Cr, Cu, Cd and Pb remained mostly in bio-char while As was present largely in the aqueous phase. Thus, this study demonstrated that the APR for HTL process in ethanol-water co-solvent can be a hopeful method to dispose the high-protein biomass for improved bio-oil yield and quality.

Fuel published new progress about Alcohols Role: TEM (Technical or Engineered Material Use), USES (Uses). 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Product Details of C7H12O3.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Vilanculo, Castelo Bandane published the artcileH4SiW12O40-Catalyzed Levulinic Acid Esterification at Room Temperature for Production of Fuel Bioadditives, Application of Ethyl 4-oxopentanoate, the main research area is levulinic acid esterification silicotungstic acid catalyst fuel bioadditive.

In this work, a route to synthesize bioadditives through H4SiW12O40-catalyzed levulinic acid esterification reactions with alcs. of short chain at room temperature was assessed. Among the Bronsted acids assessed (i.e., sulfuric, p-toluenesulfonic, silicotungstic, phosphomolybdic and phosphotungstic acids), H4SiW12O40 was the most active and selective catalyst. High conversions (ca. 90%) and selectivity (90-97%) for alkyl levulinates with carbon chain size ranging from C6 to C10 were obtained. The effect of main reaction parameters was studied, with a special focus on the reaction temperature, stoichiometry of reactants, concentration and nature of the catalyst. Insights on reaction mechanism were done and the activity of heteropoly catalysts was discussed based on acid strength and softness of the heteropolyanions. The use of renewable raw material, the mild reaction conditions (i.e., room temperature), and a recyclable solid catalyst are the some of the pos. features of this process. The alkyl levulinates obtained are renewable origin bioadditives that can be blended either to gasoline or diesel.

Waste and Biomass Valorization published new progress about Bronsted acids Role: CAT (Catalyst Use), PRP (Properties), USES (Uses). 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Application of Ethyl 4-oxopentanoate.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Tang, Ke published the artcileChemical and sensory characterization of cabernet sauvignon wines from the Chinese loess plateau region, Name: Ethyl 3-hydroxybutanoate, the main research area is cabernet sauvignon wine chem sensory profile China; Cabernet Sauvignon; GC–O; Loess Plateau; aroma; sensory profile.

In this study, the aroma profiles of Cabernet Sauvignon wines from a new grape growing region, Loess Plateau, China, were established by gas chromatog.-olfactometry, gas chromatog.-mass spectrometry and sensory anal. The sensory profiles of wines form five different young vineyards in the Loess Plateau region were obtained by descriptive anal. Blackcurrant (p < 0.01), pear and dried plum (p < 0.05), mushroom, smoked and green pepper (p < 0.1) had significant differences on the five vineyards. A total of 76 odor-active aroma compounds were identified in the wines, and 45 volatile compounds were selected as those having the greatest impact on the aroma components and these were quantitated by five different methods. In addition, the correlation model of the Loess Plateau region's sensory characteristics and aroma compounds was established by partial least squares regression (PLSR) to determine the influence of various aroma active substances on aroma attributes. Molecules published new progress about Acids Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, Name: Ethyl 3-hydroxybutanoate.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Abouelenein, Doaa published the artcileInfluence of Freezing and Different Drying Methods on Volatile Profiles of Strawberry and Analysis of Volatile Compounds of Strawberry Commercial Jams, Formula: C6H12O3, the main research area is freezing drying volatile compound strawberry com jam; HS-SPME/GC-MS; aroma; commercial jams; drying methods; freezing; strawberry; volatile organic compounds.

Strawberry is the most consumed berry fruit worldwide due to its unique aroma and flavor. Drying fruits to produce a powder represents one of the possible conservation methods to extend their shelf-life. The aim of the present study was to compare the influence of freezing and different drying methods on the volatile profile of strawberry using the HS-SPME/GC-MS method, in addition to anal. of strawberry jam volatiles. A total of 165 compounds were identified, accounting for 85.03-96.88% of the total volatile compositions Results and PCA showed that freezing and each drying process affected the volatile profile in a different way, and the most remarkable representative differential volatiles were Et hexanoate, hexyl acetate, (E)-2-hexenyl acetate, mesifurane, (E)-nerolidol, γ-decalactone, 1-hexanol, and acetoin. Shade air-dried, frozen, freeze-dried, and oven-dried 45°C samples retained more of the fruity and sweet aromas of strawberry, representing more than 68% of the total aroma intensity according to the literature. In contrast, the microwave-drying method showed drastic loss of fruity esters. Strawberry jams demonstrated complete destruction of esters and alcs. in most jams, while terpenes were significantly increased. These findings help better understand the aroma of strawberry and provide a guide for the effects of drying, freezing, and jam processing.

Molecules published new progress about Acids Role: FFD (Food or Feed Use), BIOL (Biological Study), USES (Uses). 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, Formula: C6H12O3.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Vyviurska, Olga published the artcileEnhanced multi-stir bar sorptive extraction for wine analysis: Alteration in headspace mode, Related Products of esters-buliding-blocks, the main research area is wine multi stir bar sorptive extraction; Botrytized wines; Comprehensive two-dimensional gas chromatography; Multi-SBSE; Tokaj wine region.

Multi-stir bar sorptive extraction (multi-SBSE) represents a viable alternative for recent trends in sample preparation based on a combination of extraction techniques. In this case, increased amount of sorbent and its extended polarity range could advance quality of exptl. data obtained in foodomics or metabolomics investigations. With this in mind, it was developed multi-SBSE procedure suitable for authentication of botrytized wine produced in different countries of Tokaj wine region. A design of headspace mode of multi-SBSE was modified to provide addnl. agitation of a stir bar. An expanded profile of wine samples was obtained with the application of EG-Silicone and PDMS coated stir bars in headspace and direction immersion mode, resp. Multivariate optimization based on central composite design was selected to determine the influence of various exptl. parameters, including extraction temperature enhancing headspace extraction In our case, proper description of the optimization results required application of a third-order polynomial model, which highlighted dominant influence of salt addition for extraction in both modes. Due to a large number of extracted compounds, comprehensive two-dimensional gas chromatog. (GC x GC) was used for assessment of wine samples. Such approach allows reveleaing the presence of sulfur containing compounds, diols, ketone derivatives and methoxybenzenes linking a specific geog. origin. At the same time, the results obtained for compounds common for all the samples were processed with principal component anal. (PCA). Considerable progress for discrimination of the botrytized wines was mainly achieved with combined data from EG-Silicone and PDMS extraction

Food Research International published new progress about Acids Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 623-50-7 belongs to class esters-buliding-blocks, name is Ethyl 2-hydroxyacetate, and the molecular formula is C4H8O3, Related Products of esters-buliding-blocks.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Perestrelo, Rosa published the artcileUntargeted fingerprinting of cider volatiles from different geographical regions by HS-SPME/GC-MS, HPLC of Formula: 5405-41-4, the main research area is untargeted fingerprinting cider volatile headspace solid phase microextraction.

The volat. fingerprint of ciders produced in different geog. regions from Madeira Island was established using headspace solid phase microextraction combined with gas chromatog. mass spectrometry (HS-SPME/GC-MS) in order to explore the effects of geog. region on the volatile pattern ciders in addition to identify potential mol. geog. markers. A total of 107 volatile organic compounds (VOCs) belonging to different chem. families were identified from which 50 VOCs are common to all ciders analyzed. Significant differences in the relative content of VOCs from ciders of different geog. regions were observed The potential of the identified VOCs for ciders discrimination according to region was assessed through chemometric tools, such as principal components anal. (PCA) and partial least squares-discriminant anal. (PLS-DA). The PCA showed significant differences among ciders from different island geog. regions. Fifteen VOCs responsible for ciders discrimination were identified by PLS-DA. Fifteen VOCs, namely five terpenoids, four alcs., three acids and three esters, present variable importance in projection (VIP) values higher than one. Our findings provide relevant information related to volatile signature of ciders produced in Madeira Island, which may be a useful tool to cider-making process contributing to improve the quality of the final product. In addition, the geog. discrimination recognizes the unique and distinctive characteristics that will allow in the future to protect the quality and typicity of products originating in certain geog. regions.

Microchemical Journal published new progress about Acids Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, HPLC of Formula: 5405-41-4.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Simonato, Barbara published the artcileEffects of post-harvest fungal infection of apples on chemical characteristics of cider, Formula: C6H12O3, the main research area is fungal infection apple cider.

The impact of fungal post-harvest infection of apple on the chem. composition of cider was investigated through a comparative anal. of ciders obtained from apples (Gala variety) sep. infected by five fungal species (Alternaria alternata, Botrytis cinerea, Diplodia seriata, Monilinia fructigena, and Penicillium expansum) and cider from sound apples. The content of several flavor-active mols. belonging to different chem. groups, such as alcs., esters, acids, aldehydes, phenols, and lactones, significantly varied among ciders. Particularly, cider from sound apples had a higher concentration of Et ester acetate, fatty acid Et esters and fatty acids, mols. that contribute to fruity and sweet scent. Principal component anal. well discriminated ciders, evidencing species-specific fungal effect. Differences in precursor availability in juices and biosynthesis pathways in fungi could explain changes in aroma profile of ciders. This study provides information on the potential risk to produce cider from infected apples due to the possible quality depreciation.

LWT–Food Science and Technology published new progress about Acids Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, Formula: C6H12O3.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics