Category: esters-buliding-blocks

Electrochemical reduction of oxygen: an alternative method to prepare active CoN₄ catalysts was written by Bouwkamp-Wijnoltz, A. L.;Visscher, W.;Van Veen, J. A. R.;Tang, S. C.. And the article was included in Electrochimica Acta in 1999.SDS of cas: 2199-49-7 This article mentions the following:

An alternative method for preparing active catalysts for oxygen reduction with a similar performance as heat treated cobalt porphyrin on carbon is presented. The catalysts were prepared from cobalt acetate, carbon black and a nitrogen donor. Several nitrogen donors were studied. The best results were obtained with 2,5-dimethylpyrrole. In this case the activity of the heat treated cobalt porphyrin could be matched. EXAFS indicated that similar active sites were found on both types of catalyst, although in the alternative catalyst some metallic cobalt is also present. In the experiment, the researchers used many compounds, for example, Ethyl 4-methyl-1H-pyrrole-3-carboxylate (cas: 2199-49-7SDS of cas: 2199-49-7).

Ethyl 4-methyl-1H-pyrrole-3-carboxylate (cas: 2199-49-7) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Cyclic esters are called lactones, regardless of whether they are derived from an organic or inorganic acid. One example of an organic lactone is γ-valerolactone.SDS of cas: 2199-49-7

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

Steady-State Based Model of Airborne Particle/Gas and Settled Dust/Gas Partitioning for Semivolatile Organic Compounds in the Indoor Environment was written by Li, Hai-Ling;Yang, Pu-Fei;Liu, Li-Yan;Gong, Bei-Bei;Zhang, Zi-Feng;Ma, Wan-Li;Macdonald, Robie W.;Nikolaev, Anatoly N.;Li, Yi-Fan. And the article was included in Environmental Science & Technology in 2022.Name: Dicyclohexyl phthalate This article mentions the following:

Indoor semivolatile organic compounds (SVOCs), present in the air, airborne particles, settled dust, and other indoor surfaces, can enter the human body through several pathways. Knowing the partitioning between gaseous and particulate phases is important in identifying specific pathway contributions and thereby accurately assessing human exposure. Numerous studies have developed equilibrium equations to predict airborne particle/gas (P/G) partitioning in air (K_P) and dust/gas (D/G) partitioning in settled dust (K_D). The assumption that P/G and D/G equilibrium are instantaneous for airborne and settled dust phases, commonly adopted by current indoor fate models, is not likely valid for compounds with high octanol-air partition coefficients (K_OA). Here, we develop steady-state based equations to predict K_P and K_D in the indoor environment. Results show that these equations perform well and are verified by worldwide monitoring data. It is suggested that instantaneous steady state could work for P/G and D/G partitioning of SVOCs in indoor environments, and the equilibrium is just a special case of the steady state when log K_OA < 11.38 for P/G partitioning and log K_OA < 10.38 for D/G partitioning. These newly developed equations and methods provide a tool for more accurate assessment for human exposure to SVOCs in the indoor environment. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Name: Dicyclohexyl phthalate).

Dicyclohexyl phthalate (cas: 84-61-7) belongs to esters. Esters are widespread in nature and are widely used in industry. In nature, fats are in general triesters derived from glycerol and fatty acids. Esters are responsible for the aroma of many fruits, including apples, durians, pears, bananas, pineapples, and strawberries. Esters contain a carbonyl center, which gives rise to 120° C–C–O and O–C–O angles. Unlike amides, esters are structurally flexible functional groups because rotation about the C–O–C bonds has a low barrier. Their flexibility and low polarity is manifested in their physical properties; they tend to be less rigid (lower melting point) and more volatile (lower boiling point) than the corresponding amides. Name: Dicyclohexyl phthalate

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

Contaminant occurrence, mobility and ecological risk assessment of phthalate esters in the sediment-water system of the Hangzhou Bay was written by Wang, Liu-Yong;Gu, Yan-Yu;Zhang, Ze-Ming;Sun, Ai-Li;Shi, Xi-Zhi;Chen, Jiong;Lu, Yin. And the article was included in Science of the Total Environment in 2021.Name: Dicyclohexyl phthalate This article mentions the following:

The pollution characteristics, spatiotemporal variation, sediment-water partitioning, and potential ecol. risk assessment of phthalate esters (PAEs) in the sediment-seawater system of the Hangzhou Bay (HZB) in summer and autumn were researched. The sum of the concentrations of the 10 PAEs in seawater ranges from 7305 ng/L to 22,861 ng/L in summer and from 8100 ng/L to 33,329 ng/L in autumn, with mean values of 15,567 ± 4390 and 17,884 ± 6850 ng/L, resp. The Σ16PAEs in the sediments are between 118 and 5888μg/kg and 145 and 4746μg/kg in summer and autumn, resp. The level of PAEs in seawater varies with the seasons, but it is relatively stable in the sediments. Di(2-ethylhexyl) phthalate (DEHP), di-Bu phthalate (DnBP), and diisobutyl phthalate (DiBP) are the predominant PAE congeners in the HZB. The DnBP and DiBP concentrations in seawater are greater than the DEHP concentration, which is the opposite in the sediments. The sediment-seawater equilibrium distribution study indicates that the PAEs with medium mol. weights, such as DiBP, Bu benzyl phthalate, and DnBP, are near dynamic equilibrium in the sediment-seawater system; PAEs with high mol. weights (e.g., di-n-octyl phthalate and DEHP) tend to transfer from water to the sediments; and PAEs with low mol. weights (e.g., di-Me phthalate, di-Et phthalate, and diamyl phthalate) tend to spread to seawater. The risk assessment results in seawater indicate that DEHP and DiBP might pose high potential risks to sensitive organisms, and DnBP might exhibit medium ecol. risks. In the sediment, DiBP might display a high potential risk to fish, and the potential risk of DEHP is high in several sites. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Name: Dicyclohexyl phthalate).

Dicyclohexyl phthalate (cas: 84-61-7) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Esters contain a carbonyl center, which gives rise to 120° C–C–O and O–C–O angles. Unlike amides, esters are structurally flexible functional groups because rotation about the C–O–C bonds has a low barrier. Their flexibility and low polarity is manifested in their physical properties; they tend to be less rigid (lower melting point) and more volatile (lower boiling point) than the corresponding amides. Name: Dicyclohexyl phthalate

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

Poly(N-isopropylacrylamide) capped plasmonic nanoparticles as resonance intensity-based temperature sensors with linear correlation was written by Liu, Yiyi;Dai, Xiaohui;Mallawaarachchi, Sudaraka;Hapuarachchi, Harini;Shi, Qianqian;Dong, Dashen;Thang, San H.;Premaratne, Malin;Cheng, Wenlong. And the article was included in Journal of Materials Chemistry C: Materials for Optical and Electronic Devices in 2017.Recommanded Product: 27249-90-7 This article mentions the following:

Thermosensitive polymer capped plasmonic nanoparticles are novel thermal nanofluids with potential sensing applications. Previous research efforts were focused only on monitoring plasmonic resonance peak shifts caused by aggregation as temperature varied. However, to date, no linear relation between the resonance peak shift and temperature was established. Here, the authors systematically study how plasmonic resonance peak intensity responds to solution temperature using poly(N-isopropylacrylamide)-capped Au nanorods (AuNRs) and nanobipyramids (AuNBPs) under aggregation-free conditions. Results clearly reveal the linear correlation between longitudinal resonance peak intensity and solution temperature for both types of particles. AuNBPs have sharper ends than AuNRs, resulting in greater thermo-sensitivity due to the presence of stronger hot spots. Further anal. and numerical studies demonstrate chem. interface damping effects by surface-capping ligand configurational changes and these theor. results agree well with exptl. observations. This damping-based sensing is reversible with excellent durability, indicating the possibility of potential real-world temperature sensing applications. In the experiment, the researchers used many compounds, for example, Benzyl benzodithioate (cas: 27249-90-7Recommanded Product: 27249-90-7).

Benzyl benzodithioate (cas: 27249-90-7) belongs to esters. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. Liquid esters of low volatility serve as softening agents for resins and plastics. Esters also include many industrially important polymers. Polymethyl methacrylate is a glass substitute sold under the names Lucite and Plexiglas; polyethylene terephthalate is used as a film (Mylar) and as textile fibres sold as Terylene, Fortrel, and Dacron.Recommanded Product: 27249-90-7

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

Quality assessment of environmental water by a simple and fast non-ionic hydrophobic natural deep eutectic solvent-based extraction procedure combined with liquid chromatography tandem mass spectrometry for the determination of plastic migrants was written by Santana-Mayor, Alvaro;Socas-Rodriguez, Barbara;Rodriguez-Ramos, Ruth;Herrera-Herrera, Antonio V.;Rodriguez-Delgado, Miguel Angel. And the article was included in Analytical and Bioanalytical Chemistry in 2021.Safety of Dicyclohexyl phthalate This article mentions the following:

A non-ionic hydrophobic natural deep eutectic solvent (HNADES) based on thymol and menthol was proposed for the liquid-liquid microextraction of fourteen phthalates and one adipate from environmental water samples. Separation, identification, and quantification were achieved by ultra-high-performance liquid chromatog. coupled to tandem mass spectrometry. The main factors affecting the extraction efficiency were thoroughly studied. Sample pH of 8 and 100 μL of thymol:menthol at molar ratio 2:1 were selected as the best conditions, while ionic strength and type of dispersant solvent were not relevant for the extraction of the target compounds The whole methodol. was validated for treated wastewater, runoff, and pond water matrixes, using di-Bu phthalate-3,4,5,6-d4 and dihexyl phthalate-3,4,5,6-d4 as surrogates. Recovery ranged from 70 to 127% with relative standard deviation values lower than 14%. Limits of quantification of the method were in the range 0.042-0.425 μg/L for treated wastewater, 0.015-0.386 μg/L for runoff, and 0.013-0.376 μg/L for pond water. The methodol. was applied for the anal. of real treated wastewater, runoff, and pond water samples from different places of Tenerife and Gran Canaria (Canary Islands) finding the presence of di-Et phthalate, diallyl phthalate, di-Pr phthalate, benzylbutyl phthalate, di-Bu phthalate, bis-(2-n-butoxyethyl) phthalate, di-n-pentyl phthalate, dicyclohexyl phthalate, and bis-(2-ethylhexyl) phthalate at concentrations between 105.2 and 3414 ng/L. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Safety of Dicyclohexyl phthalate).

Dicyclohexyl phthalate (cas: 84-61-7) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Because of their lack of hydrogen-bond-donating ability, esters do not self-associate. Consequently, esters are more volatile than carboxylic acids of similar molecular weight.Safety of Dicyclohexyl phthalate

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

Isosteric Substitution of 4H-1,2,4-Triazole by 1H-1,2,3-Triazole in Isophthalic Derivative Enabled Hydrogel Formation for Controlled Drug Delivery was written by Haering, Marleen;Rodriguez-Lopez, Julio;Grijalvo, Santiago;Tautz, Markus;Eritja, Ramon;Martin, Victor S.;Diaz Diaz, David. And the article was included in Molecular Pharmaceutics in 2018.Computed Properties of C12H10O4 This article mentions the following:

In this work, we demonstrated that the simple substitution of the 1,2,4-triazole moiety in 5-(4H-1,2,4-triazol-4-yl)isophthalic acid (5-TIA) by the 1H-1,2,3-triazol-5-yl unit enables the preparation of a hydrogelator (click-TIA). In sharp contrast to 5-TIA, its isostere click-TIA undergoes self-assembly in water upon sonication, leading to the formation of stable supramol. viscoelastic hydrogels with a critical gelation concentration of 6 g/L. Hydrogels made of click-TIA as well as hybrid hydrogels made of the mixture click-TIA + 5-TIA (molar ratio 1:0.2) were used to compare different properties of the materials (i.e., rheol. properties, thermal properties, mech. stability, morphol.). In terms of toxicity, neither click-TIA nor 5-TIA showed cytotoxic effects on cellular viability of HeLa cells up to 2.3 × 10^-3 g/L when compared to untreated cells incubated with DMSO. Furthermore, the hydrogels were used for the encapsulation and in vitro controlled release of oxytetracycline that followed first-order kinetics. For the hydrogel made of click-TIA, a maximum drug release of âˆ?0% was reached after âˆ? h within a pH range between 6.5 and 10. However, the release rate was reduced to approx. half of its value at pH values between 1.2 and 5.0, whereas the use of hybrid hydrogels made of click-TIA + 5-TIA allowed to reduce the original rate at pH â‰?6.5. In the experiment, the researchers used many compounds, for example, Dimethyl 5-ethynylisophthalate (cas: 313648-56-5Computed Properties of C12H10O4).

Dimethyl 5-ethynylisophthalate (cas: 313648-56-5) belongs to esters. Esters are widespread in nature and are widely used in industry. In nature, fats are in general triesters derived from glycerol and fatty acids. Esters are responsible for the aroma of many fruits, including apples, durians, pears, bananas, pineapples, and strawberries. Esters are more polar than ethers but less polar than alcohols. They participate in hydrogen bonds as hydrogen-bond acceptors, but cannot act as hydrogen-bond donors, unlike their parent alcohols. This ability to participate in hydrogen bonding confers some water-solubility.Computed Properties of C12H10O4

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

Comparative evaluation of the volatile profiles and taste properties of roasted coffee beans as affected by drying method and detected by electronic nose, electronic tongue, and HS-SPME-GC-MS was written by Dong, Wenjiang;Hu, Rongsuo;Long, Yuzhou;Li, Hehe;Zhang, Yanjun;Zhu, Kexue;Chu, Zhong. And the article was included in Food Chemistry in 2019.Reference of 118-61-6 This article mentions the following:

In this study, room-temperature drying, solar drying, heat pump drying (HPD), hot-air drying, and freeze drying were applied to investigate the volatile profiles and taste properties of roasted coffee beans by using electronic nose, electronic tongue, and headspace solid-phase microextraction gas chromatog.-mass spectrometry (HS-SPME-GC-MS). Results indicated that the drying process markedly affected pH, total titratable acidity, total solids, and total soluble solids. Significant differences existed among all samples based on drying method; and the HPD method was superior for preserving ketones, phenols, and esters. Principal component anal. (PCA) combined with E-nose and E-tongue radar charts as well as the fingerprint of HS-SPME-GC-MS could clearly discriminate samples from different drying methods, with results obtained from hierarchical cluster anal. (the Euclidean distance is 0.75) being in agreement with those of PCA. These findings may provide a theor. basis for the dehydration of coffee beans and other similar thermo-sensitive agricultural products. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxybenzoate (cas: 118-61-6Reference of 118-61-6).

Ethyl 2-hydroxybenzoate (cas: 118-61-6) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Acyl chlorides and acid anhydrides alcoholysis is another way to produce esters. Acyl chlorides and acid anhydrides react with alcohols to produce esters. Anydrous conditions are recommended since both acyl chlorides and acid anhydrides react with water.Reference of 118-61-6

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

Catalytic dynamic kinetic resolutions with N-heterocyclic carbenes: Asymmetric synthesis of highly substituted β-lactones was written by Cohen, Daniel T.;Eichman, Chad C.;Phillips, Eric M.;Zarefsky, Emily R.;Scheidt, Karl A.. And the article was included in Angewandte Chemie, International Edition in 2012.Safety of Ethyl 3-oxo-3-(m-tolyl)propanoate This article mentions the following:

A new NHC-catalyzed (N-heterocyclic carbenes) DKR (dynamic kinetic resolution) with β-keto esters to generate highly substituted β-lactones with excellent levels of stereoselectivity has been developed. This process takes advantage of the conditions necessary to generate the active NHC catalyst to simultaneously promote the epimerization of a β-ketoester substrate. The present study provides efficient access to highly enantioenriched β-lactones and cyclopentenes in good yield with good to excellent diastereoselectivity. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(m-tolyl)propanoate (cas: 33166-79-9Safety of Ethyl 3-oxo-3-(m-tolyl)propanoate).

Ethyl 3-oxo-3-(m-tolyl)propanoate (cas: 33166-79-9) belongs to esters. Esters are widespread in nature and are widely used in industry. In nature, fats are in general triesters derived from glycerol and fatty acids. Esters are responsible for the aroma of many fruits. Because of their lack of hydrogen-bond-donating ability, esters do not self-associate. Consequently, esters are more volatile than carboxylic acids of similar molecular weight.Safety of Ethyl 3-oxo-3-(m-tolyl)propanoate

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

Organocatalyzed Asymmetric Tandem Intramolecular oxa-Michael Addition/Electrophilic Thiocyanation: Synthesis of Chiral α-Thiocyanato Flavanones was written by Gao, Yong;Fu, Zhenda;Wu, Di;Yin, Hongquan;Chen, Fu-Xue. And the article was included in Asian Journal of Organic Chemistry in 2022.Synthetic Route of C9H10O3 This article mentions the following:

An efficient bifunctional cinchona alkaloids-catalyzed asym. tandem intramol. oxa-Michael addition/electrophilic thiocyanation of alkylidene β-ketoesters with N-thiocyanatosuccinimide (NTS) was developed. A series of chiral α-thiocyanato flavanones containing two vicinal stereocenters including an all-carbon quaternary center I [R¹ = H, 7-Me, 6-Cl; R² = Ph, 2-naphthyl, 2-thienyl, etc.; R³ = Me, Et, t-Bu] were prepared in good yields with excellent diastereo- and enantioselectivities (up to 97% ee) under mild conditions, and a successful scale up preparation of our protocol was also demonstrated. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxybenzoate (cas: 118-61-6Synthetic Route of C9H10O3).

Ethyl 2-hydroxybenzoate (cas: 118-61-6) belongs to esters. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. Many esters have the potential for conformational isomerism, but they tend to adopt an s-cis (or Z) conformation rather than the s-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.Synthetic Route of C9H10O3

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

Measurement of the Effect of Accelerated Aging on the Aromatic Compounds of Gewurztraminer and Teroldego Wines, Using a SPE-GC-MS/MS Protocol was written by Carlin, Silvia;Lotti, Cesare;Correggi, Ludovica;Mattivi, Fulvio;Arapitsas, Panagiotis;Vrhovsek, Urska. And the article was included in Metabolites in 2022.Product Details of 706-14-9 This article mentions the following:

Knowing in detail how the white and red wine aroma compounds behave under various storage conditions and especially at high temperature is important in order to understand the changes occurring to their sensorial character during the shelf life. The initial aim of this work was to develop and validate a fast, modern, robust, and comprehensive protocol for the quantification of 64 primary, secondary, and tertiary volatile compounds by using solid-phase extraction (SPE) cartridges in sample preparation and fast GC-MS/MS (gas chromatog.-tandem mass spectrometry assay) in anal. The protocol was applied to a study of the behavior of seven Gewurztraminer and seven Teroldego wines stored in anoxia at 50°C for 2.5 and 5 wk. The results demonstrated a sharp decrease of the main linear terpenes linalool, geraniol, and nerol and the consequent increase of the cyclic ones, such as α-terpineol and 1,8-cineole; the increase of the C13-norisoprenoids 1,1,6,-trimethyl-1,2-dihydronaphthalene (TDN), and β-damascenone and the C10 norisoprenoid safranal; the hydrolysis of acetates and linear esters; and the increase of some branched-chain esters. In red wines, a moderate increase was observed for some lactones. Some unwanted compounds, such as 2-aminoacetophenone (2-AAP), showed a notable increase in some Gewurztraminer wines, exceeding the olfactory threshold. In the experiment, the researchers used many compounds, for example, 5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9Product Details of 706-14-9).

5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Cyclic esters are called lactones, regardless of whether they are derived from an organic or inorganic acid. One example of an organic lactone is γ-valerolactone.Product Details of 706-14-9

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