Category: esters-buliding-blocks

Recovery of wolframite from tungsten mine tailings by the combination of shaking table and flotation with a novel ”crab” structure sebacoyl hydroxamic acid was written by Huang, Zhiqiang;Zhang, Shiyong;Wang, Hongling;Liu, Rukuan;Cheng, Chen;Shuai, Shuyi;Hu, Yajing;Zeng, Yuhui;Yu, Xinyang;He, Guichun;Fu, Weng;Burov, Vladimir E.;Poilov, Vladimir Z.. And the article was included in Journal of Environmental Management in 2022.Recommanded Product: 106-79-6 This article mentions the following:

Tailings ponds for gangue mineral storage are widely recognized as a dangerous source of toxic minerals and heavy metal-bearing solution Therefore, recovering valuable minerals and critical elements from tailings is an important means to protect the environment in an economic way. Wolframite tailings usually contain a considerable amount of tungsten resources, but the presence of high content of kaolinite sludge makes it very difficult to recycle wolframite. Herein, a novel sebacoyl hydroxamic acid (SHA) was synthesized and introduced as a novel wolframite collector to effectively utilize wolframite tailings, and its collection performance was compared with that of benzohydroxamic acid (BHA). Micro-flotation tests showed that SHA could still obtain 80% wolframite recovery in the presence of kaolinite slimes. Bench-scale flotation tests indicated that SHA can effectively recover wolframite concentrate with 55.64% WO₃ grade and 75.28% WO₃ recovery from wolframite tailings by the combined shaking table-flotation process. Polarized light microscope observations showed that SHA could promote the formation of hydrophobic agglomerates of wolframite particles. These results show that SHA can be used as an efficient collector for disposing of wolframite tailings, and provide an important reference for the development of efficient and comprehensive utilization of tailings. In the experiment, the researchers used many compounds, for example, Dimethyl decanedioate (cas: 106-79-6Recommanded Product: 106-79-6).

Dimethyl decanedioate (cas: 106-79-6) belongs to esters. Volatile esters with characteristic odours are used in synthetic flavours, perfumes, and cosmetics. Certain volatile esters are used as solvents for lacquers, paints, and varnishes. 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.Recommanded Product: 106-79-6

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

An approach to classifying occupational exposures to endocrine disrupting chemicals by sex hormone function using an expert judgment process was written by Prichystalova, R.;Caron-Beaudoin, E.;Richardson, L.;Dirkx, E.;Amadou, A.;Zavodna, T.;Cihak, R.;Cogliano, V.;Hynes, J.;Pelland-St-Pierre, L.;Verner, M. A.;van Tongeren, M.;Ho, V.. And the article was included in Journal of Exposure Science & Environmental Epidemiology in 2021.Reference of 84-61-7 This article mentions the following:

Endocrine disrupting chems. (EDCs) are exogenous substances that interfere with the endocrine system and cause adverse effects. We aimed to classify the effects of 24 known EDCs, prevalent in certain occupations, according to four modes of action (estrogenic, antiestrogenic, androgenic, and/or antiandrogenic). The state of the evidence of each EDC on sex hormone function was summarized and reviewed by an expert panel. For each mode of action, the experts evaluated the likelihood of endocrine disruption in five categories: “No”, “Unlikely”, “Possibly”, “Probably”, and “Yes”. Seven agents were categorized as “Yes,” or having strong evidence for their effects on sex hormone function (antiandrogenic: lead, arsenic, butylbenzyl phthalate, di-Bu phthalate, dicyclohexyl phthalate; estrogenic: nonylphenol, bisphenol A). Nine agents were categorized as “Probable,” or having probable evidence (antiandrogenic: bis(2-ethylhexyl)phthalate, nonylphenol, toluene, bisphenol A, diisononyl phthalate; androgenic: cadmium; estrogenic: copper, cadmium and; anti-estrogenic: lead). Two agents (arsenic, polychlorinated biphenyls) had opposing conclusions supporting both “probably” estrogenic and antiestrogenic effects. This synthesis will allow researchers to evaluate the health effects of selected EDCs with an added level of precision related to the mode of action. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Reference of 84-61-7).

Dicyclohexyl phthalate (cas: 84-61-7) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. 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.Reference of 84-61-7

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

Transmission of polar effects through aromatic systems. III. Hammett σ-constants was written by Norman, R. O. C.;Radda, G. K.;Brimacombe, D. A.;Ralph, P. D.;Smith, E. M.. And the article was included in Journal of the Chemical Society in 1961.Synthetic Route of C10H11FO2 This article mentions the following:

Hydrolysis of Et phenylacetate (I) and nine monosubstituted derivatives in aqueous Me₂CO at 25° were measured. The results supported the theory of van Bekkum, Verkade, and Wepster (CA 54, 16407g) that mesomeric p-interaction between substituent and functional center may affect the σ-value of a substituent. Variations in σ-values arising from the polar effect of the substituent on the resonance interaction of the functional center with the aromatic nucleus were noted. An improved method of obtaining σ-values was proposed in which use was made only of those reaction series where resonance interaction between the functional center and the aromatic ring was precluded. Substituted phenylacetic acids were prepared by known methods and converted into their Et esters. Liquid esters were purified by fractional distillation and the solid esters recrystallized from ligroine. The following phenylacetic acids and their Et esters were obtained (substituent, m.p. of acid, m.p. of Et ester, b.p./mm. of Et ester given): H, -, -, 227°/758; m-Me, 62°, -, 122-3°/18; m-NO₂, 118-20°, 11.5-12.5°, 127-35°/0.25; p-Me, 94°, -, 134-5°/25; p-OMe, 85-6°, -, 143-4°/11; p-F, 84.5°, 34°, 128-30°/31; p-Cl, -, 33-3.5°, -; p-Br, -, 31.0-1.5°, -; p-COMe, -, 62-3°, -; p-NO₂, -, 63°, -. The procedure for rate measurements was that described by Tommila and Hinshelwood (CA 33, 1199⁶). Atm. CO₂ was excluded by alkali solutions and these were restandardized frequently. Initial concentrations of alkali and ester were equal and the extent of hydrolysis was studied from 10-80% completion. Each reaction obeyed 2nd order kinetics. The following rate constants (l. mole^-1sec.^-1) for the alk. hydrolysis of Et phenylacetates at 25° were obtained (substituent, and 10²k given): II, 4.40; m-Me, 3.58; p-Me, 3.18; p-OMe, 3.93; p-F, 6.96; p-Cl, 9.71; p-Br, 10.10; p-COMe, 13.0; m-NO₂, 18.4; p-NO₂, 26.2. The following σⁿ and σ_G values were obtained (substituent, σⁿ, and σ_G given): p-Me, -0.129, -0.129; m-Me, -0.069, -0.105; p-OMe, -0.111, -0.097; p-F, 0.168, 0.143; p-Cl, 0.238, 0.256; p-Br, 0.265, 0.281; m-Cl, 0.373, 0.334; m-NO₂, 0.710, 0.576; p-NO₂, 0.778, 0.708. The σ_G and ρ values were obtained from the following reactions (reaction, solvent, temperature, ρ, s, r, n given): ArCH₂CO₂Et + OH^–, 60% Me₂CO, 25°, 1.069, 0.029, 0.996, 8; ArCH₂CO₂Et + OH^–, 85.4% alc., 24.8, 1.168, 0.021, 0.998, 5; ArCH₂CO₂H (pK_a), H₂O, 25°, 0.612, 0.027, 0.989, 8; ArCH₂OHc + OH^-1, 56% Me₂CO, 25°, 0.894, 0.019, 0.998, 8; ArCH₂NHAc + Cl₂, 40% AcOH, 18, -1.256, 0.049, 0.987, 5. In the experiment, the researchers used many compounds, for example, Ethyl 2-(4-fluorophenyl)acetate (cas: 587-88-2Synthetic Route of C10H11FO2).

Ethyl 2-(4-fluorophenyl)acetate (cas: 587-88-2) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. 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.Synthetic Route of C10H11FO2

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

Analysis of aromatic compounds in sauce-flavor Moutai lees by GC-MS was written by Zhang, Shixian;Jin, Qian;Zeng, Qihua;Gao, Zhixi. And the article was included in Zhongguo Niangzao in 2012.SDS of cas: 15399-05-0 This article mentions the following:

Aromatic compounds of Moutai lees were extracted by steam distillation and isolated by gas chromatog.-mass spectrometry. Thirty-two kinds of ingredients were identified, including furfural, Et linoleate, Et palmitate, Et oleate, 5-methyl-2-furfural, phenethyl alc., 2-formylpyrrole, benzaldehyde, hyacinthin, 2-acetylfuran, furfuralc., 2,3,5,6-tetra-Me pyrazine, Et 9-hexadecanoate, ethyl-2-hydroxy-3-phenylpropanoate, Et stearate, 3-acetylpyrrole and phytane, etc. They were main components of the sauce-flavor Moutai lees, counted for up to 93.9%. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxy-3-phenylpropanoate (cas: 15399-05-0SDS of cas: 15399-05-0).

Ethyl 2-hydroxy-3-phenylpropanoate (cas: 15399-05-0) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. 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. SDS of cas: 15399-05-0

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

Highly efficient asymmetric michael addition reaction of malonates to α,β-unsaturated ketones promoted by a chiral thiourea/PPY dual-catalyst system was written by Moritaka, Maya;Miyamae, Naomu;Nakano, Keiji;Ichikawa, Yoshiyasu;Kotsuki, Hiyoshizo. And the article was included in Synlett in 2012.Formula: C10H14O4 This article mentions the following:

The enantioselective Michael addition reaction of malonates to α,β-unsaturated ketones is efficiently promoted by a combined dual-catalyst system composed of chiral thiourea and 4-pyrrolidinopyridine (PPY) in toluene. The expected Michael adducts with cyclic and acyclic enones are obtained in excellent yields and with excellent enantioselectivities. In the experiment, the researchers used many compounds, for example, Diethyl 2-(prop-2-yn-1-yl)malonate (cas: 17920-23-9Formula: C10H14O4).

Diethyl 2-(prop-2-yn-1-yl)malonate (cas: 17920-23-9) 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. 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.Formula: C10H14O4

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

Rhodium(III)-catalyzed sulfonamide directed ortho C-H carbenoid functionalization via metal carbene migratory insertion was written by Dong, Yi;Chen, Jiajing;Xu, Heng. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2019.Application In Synthesis of Methyl 2-(methylsulfonyl)acetate This article mentions the following:

A rhodium(III)-catalyzed sulfonamide directed ortho C-H carbenoid functionalization was developed with good yields. This method was attractive due to its broad substrate scope and enabled derivation of diverse biol. active sulfonamide structures and late-stage modification of sulfa drugs. In the experiment, the researchers used many compounds, for example, Methyl 2-(methylsulfonyl)acetate (cas: 62020-09-1Application In Synthesis of Methyl 2-(methylsulfonyl)acetate).

Methyl 2-(methylsulfonyl)acetate (cas: 62020-09-1) 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.Application In Synthesis of Methyl 2-(methylsulfonyl)acetate

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

Enantioselective Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones through Organocatalytic Transfer Hydrogenation of 2-Hydroxypyrimidines was written by Meng, Fan-Jie;Shi, Lei;Feng, Guang-Shou;Sun, Lei;Zhou, Yong-Gui. And the article was included in Journal of Organic Chemistry in 2019.Quality Control of Ethyl 3-oxo-3-(m-tolyl)propanoate This article mentions the following:

Chiral phosphoric acid-catalyzed transfer hydrogenation of 2-hydroxypyrimidines has been successfully realized using Hantzsch ester or dihydrophenanthridine as the hydrogen source, furnishing the chiral 3,4-dihydropyrimidin-2(1H)-ones (DHPMs) with excellent yields and enantioselectivities of �9%. Notably, a novel kind of chiral DHPMs with an alkyl stereogenic center can be prepared through highly chemoselective transfer hydrogenation. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(m-tolyl)propanoate (cas: 33166-79-9Quality Control of Ethyl 3-oxo-3-(m-tolyl)propanoate).

Ethyl 3-oxo-3-(m-tolyl)propanoate (cas: 33166-79-9) belongs to esters. Esters are also usually derived from carboxylic acids. It may also be obtained by reaction of acid anhydride or acid halides with alcohols or by the reaction of salts of carboxylic acids with alkyl halides. 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.Quality Control of Ethyl 3-oxo-3-(m-tolyl)propanoate

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

Regioregularity and Electron Deficiency Control of Unsymmetric Diketopyrrolopyrrole Copolymers for Organic Photovoltaics was written by Aoshima, Kenta;Nomura, Mayuka;Saeki, Akinori. And the article was included in ACS Omega in 2019.Safety of Ethyl 3-oxo-3-(thiophen-2-yl)propanoate This article mentions the following:

Manipulating the electron deficiency and controlling the regioregularity of π-conjugated polymers are important for the fine-tuning of their electronic and electrochem. properties to make them suitable for an organic solar cell. Here, we report such a mol. design of unsym. diketopyrrolopyrrole (DPP) based copolymers with different aromatic side units of either thiophene (Th), pyridine (Py), or fluorobenzene (FBz). The unsym. electron acceptors of Th-DPP-Py and Th-DPP-FBz were polymerized with the electron donor of two-dimensional benzobisthiophene (BDT-Th), affording two regiorandom DPP copolymers. They exhibited contrasting MO levels and bulk heterojunction morphol. in methanofullerene-blended films, leading to power conversion efficiencies of 3.75 and 0.18%, resp. We further synthesized a regioregular DPP copolymer via sandwiching the centrosym. BDT-Th unit by two Th-DPP-Py units in an axisym. manner. The extensive characterization through morphol. observation, X-ray diffraction, and space-charge-limited current mobilities highlight the case-dependent pos./neg. effects of regioregularity and electron deficiency control. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8Safety of Ethyl 3-oxo-3-(thiophen-2-yl)propanoate).

Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8) belongs to esters. Esters are also usually derived from carboxylic acids. It may also be obtained by reaction of acid anhydride or acid halides with alcohols or by the reaction of salts of carboxylic acids with alkyl halides. 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-(thiophen-2-yl)propanoate

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

Phenylhydrazide as an enzyme-labile protecting group in peptide synthesis was written by Voelkert, Martin;Koul, Surrinder;Mueller, Gernot H.;Lehnig, Manfred;Waldmann, Herbert. And the article was included in Journal of Organic Chemistry in 2002.Quality Control of Ethyl 2-hydroxy-3-phenylpropanoate This article mentions the following:

The enzymic cleavage of amino acid phenylhydrazides with the enzyme tyrosinase (EC 1.14.18.1) offers a new, mild, and selective method for C-terminal deprotection of peptides. The advantages of the described methodol. are the very mild oxidative removal of the protecting group at room temperature and pH 7, a high chemo- and regioselectivity, and the availability of the biocatalyst. Even in oxygen-saturated solution, the oxidation of sensitive methionine residues was not observed These features make the methodol. suitable for the synthesis of sensitive peptide conjugates. Mechanistic data suggest that the hydrolysis of the oxidized adducts proceeds by a free-radical mechanism. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxy-3-phenylpropanoate (cas: 15399-05-0Quality Control of Ethyl 2-hydroxy-3-phenylpropanoate).

Ethyl 2-hydroxy-3-phenylpropanoate (cas: 15399-05-0) 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.Quality Control of Ethyl 2-hydroxy-3-phenylpropanoate

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

Aroma composition of fruit wines. II. Bilberry wine was written by Schreier, P.;Drawert, F.. And the article was included in Chemie, Mikrobiologie, Technologie der Lebensmittel in 1982.COA of Formula: C11H14O3 This article mentions the following:

The volatile components of 2 laboratory-made and 4 com. bilberry wines were separated by liquid-liquid extraction and investigated by column chromatog. on silica gel, gas chromatog. and combined gas chromatog.-mass spectrometry. Of the aroma components, 43 compounds were identified, including, among them furfural  [98-01-1], 5-methylfurfural  [620-02-0], and Et 4-oxopentanoate  [539-88-8], in some com. samples made from juice concentrates The occurrence of 3-methylbutanoate  [503-74-2] and Et 2- [7452-79-1] and 3-methylbutanoates [108-64-5] in a com. sample, together with a large amount of benzyl alc.  [100-51-6] suggests unlawful addition of flavorings during processing. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxy-3-phenylpropanoate (cas: 15399-05-0COA of Formula: C11H14O3).

Ethyl 2-hydroxy-3-phenylpropanoate (cas: 15399-05-0) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Esterification is the general name for a chemical reaction in which two reactants (typically an alcohol and an acid) form an ester as the reaction product. Esters are common in organic chemistry and biological materials.COA of Formula: C11H14O3

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