Month: February 2023

Reaction of silyl enol ethers with arenediazonium salts. Part 2. α-Amination of esters was written by Sakakura Toshiyasu;Hara, Masayasu;Tanaka, Masato. And the article was included in Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999) in 1994.HPLC of Formula: 19432-68-9 This article mentions the following:

Diazonium salts efficiently serve as electrophilic aminating reagents of esters. The reaction of arenediazonium tetrafluoroborates with ketene silyl ketals yielded α-azo or α-hydrazono esters in good to excellent yields under very mild conditions. Hydrogenation of those esters gave α-amino esters quant. In the experiment, the researchers used many compounds, for example, Methyl 2-thienylacetate (cas: 19432-68-9HPLC of Formula: 19432-68-9).

Methyl 2-thienylacetate (cas: 19432-68-9) 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. 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.HPLC of Formula: 19432-68-9

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

Formation and rearrangement of esters. LXXII. 2-Aryl (or aralkyl or alkyl)aminotetrahydro-4H-1,3-thiazines or 2-aryl (or aralkyl or alkyl) amino-5,6-dihydro-4H-1,3-thiazines and their derivatives was written by Cherbuliez, Emile;Baehler, Bruno;Espejo, O.;Jindra, H.;Willhalm, B.;Rabinowitz, Joseph. And the article was included in Helvetica Chimica Acta in 1967.Application of 2740-88-7 This article mentions the following:

Aryl (or aralkyl) isothiocyanates, RNCS, were treated with 3-aminopropanol (I) to give thioureas, RNHCSNH(CH2)3OH, which are either 2-(R-substituted-imino)tetrahydro-4H-1,3-thiazines or 2-(R-substituted-amino)-5,6-dihydro-4H-1,4-thiazines. The structures of the hydrothiazines prepared from I and p-fluorophenyl isothiocyanate, p-bromophenyl isothiocyanate, p-fluorobenzyl isothiocyanate, ethyl isothiocyanate, or butyl isothiocyanate were established by comparing their N.M.R. spectra with those of 2-methyl-5,6-dihydro-4H-1,3-thiazine, in which the C:N bond is endo-cyclic, and of 3-methyl-2-phenyliminotetrahydro-4H-1,3-thiazine, in which the C:N bond is exo-cyclic. When R is an aryl group, the C:N bond is exo-cyclic, apparently due to resonance stabilization, while when R is aralkyl or alkyl, the C:N bond is endo-cyclic. Treatment of 2-aryliminotetrahydro-4H-1,3-thiazines with an RNCO gives the corresponding carbamoyl derivatives 3-Benzoyl-2-phenyliminotetrahydro-4H-1,3-thiazine was prepared by treating BzCl with 2-phenyliminotetrahydro-4H-1,3-thiazine in the presence of a tertiary base. In the experiment, the researchers used many compounds, for example, 4-Fluorobenzylisothiocyanate (cas: 2740-88-7Application of 2740-88-7).

4-Fluorobenzylisothiocyanate (cas: 2740-88-7) 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. 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.Application of 2740-88-7

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

Asymmetric synthesis of 1H-pyrrol-3(2H)-ones from 2,3-diketoesters by combination of aldol condensation with benzilic acid rearrangement was written by Sha, Qiang;Arman, Hadi;Doyle, Michael P.. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2016.Recommanded Product: 13669-10-8 This article mentions the following:

An efficient two-step protocol for the asym. synthesis of 1H-pyrrol-3(2H)-one derivatives in 99% ee from conveniently accessed 2,3-diketoesters was developed. E.g., aldol reaction of benzyl2,2-dihydroxy-3-oxobutanoate hydrate 1a and cyclohexanone 2a in the presence of L-proline as organocatalyst in DCM gave a 68% yield of (R)-benzyl 2-hydroxy-3-oxo-2-[(S)-2-oxocyclohexyl]butanoate (3a) and a 24% yield of (S)-benzyl 2-hydroxy-3-oxo-2-[(S)-2-oxocyclohexyl]butanoate (4a). Subsequent benzilic acid rearrangement reaction of 3a in the presence of aniline and 20 mol% CF₃CO₂H/DCM at 65° gave (R)-benzyl 2-methyl-3-oxo-1-phenyl-2,3,4,5,6,7-hexahydro-1H-indole-2-carboxylate in 87% yield. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8Recommanded Product: 13669-10-8).

Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8) 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. 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.Recommanded Product: 13669-10-8

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

Stereochemistry and tautomerism of amino acid antagonists: α,γ-diketo acids and esters and their cyclization products was written by Sheldrick, W. S.;Trowitzsch, W.. And the article was included in Zeitschrift fuer Naturforschung, Teil B: Anorganische Chemie, Organische Chemie in 1983.Application of 39163-39-8 This article mentions the following:

X-ray structural analyses of amino acid antagonists MeCOCH₂COCO₂Me (I), II, and III have shown them all to be present in the solid state in the α,β-unsaturated γ-keto enolic form. The structures of I and II are stabilized by intramol. H bonds involving the enol proton. In the case of III an intramol. H bond between the γ-keto O and the acid proton is observed The bond lengths and angles in I indicate a significant contribution from the mesomeric β,γ-unsaturated enol form. The structures of γ-enol Me ether of I and of the cyclization products IV and V are also reported. In the experiment, the researchers used many compounds, for example, Ethyl 2-oxo-2-(2-oxocyclopentyl)acetate (cas: 39163-39-8Application of 39163-39-8).

Ethyl 2-oxo-2-(2-oxocyclopentyl)acetate (cas: 39163-39-8) 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. 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.Application of 39163-39-8

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

C-H Activation-Based Traceless Synthesis via Electrophilic Removal of a Directing Group. Rhodium(III)-Catalyzed Entry into Indoles from N-Nitroso and α-Diazo-β-keto Compounds was written by Wang, Jie;Wang, Mingyang;Chen, Kehao;Zha, Shanke;Song, Chao;Zhu, Jin. And the article was included in Organic Letters in 2016.Recommanded Product: Ethyl 3-oxo-3-(m-tolyl)propanoate This article mentions the following:

A distinct C-H activation-based traceless synthetic protocol via electrophilic removal of a directing group is reported, complementing the currently exclusively used nucleophilic strategy. Rh(III)-catalyzed, N-nitroso-directed C-H activation allows the development of a traceless, atom- and step-economic, cascade approach for the synthesis of indole skeletons, starting from readily available N-nitroso and α-diazo-β-keto compounds Importantly, the cyclization/denitrosation reaction represents a hitherto unobserved reactivity pattern for the N-nitroso group. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(m-tolyl)propanoate (cas: 33166-79-9Recommanded Product: 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. 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.Recommanded Product: Ethyl 3-oxo-3-(m-tolyl)propanoate

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

Total Synthesis of Nucleoside Antibiotics Plicacetin and Streptcytosine A was written by Fu, Jiqiang;Laval, Stephane;Yu, Biao. And the article was included in Journal of Organic Chemistry in 2018.Synthetic Route of C16H22O11 This article mentions the following:

Disaccharide nucleoside antibiotics plicacetin and streptcytosine A (also named rocheicoside A) were effectively synthesized through the common precursor cytosamine. The amosamine and amicetose moieties were efficiently assembled through an α-selective O-glycosylation, and the cytosine nucleus was subsequently introduced through a β-selective gold(I)-catalyzed N-glycosylation. Further microwave-assisted amidation reactions completed the modular syntheses. In the experiment, the researchers used many compounds, for example, (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate (cas: 4163-60-4Synthetic Route of C16H22O11).

(2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate (cas: 4163-60-4) 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. 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. Synthetic Route of C16H22O11

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

Stereodivergent Synthesis of Tertiary Fluoride-Tethered Allenes via Copper and Palladium Dual Catalysis was written by Yang, Shao-Qian;Wang, Yi-Fan;Zhao, Wei-Cheng;Lin, Guo-Qiang;He, Zhi-Tao. And the article was included in Journal of the American Chemical Society in 2021.Formula: C13H15NO2 This article mentions the following:

Herein we describe a protocol for the unprecedented stereodivergent synthesis of tertiary fluoride-tethered allenes bearing a stereogenic center and stereogenic axis via Cu/Pd synergistic catalysis. A broad scope of conjugated enynes are coupled with various α-fluoroesters in high yields with high diastereoselectivities and generally >99% ee. In addition, the four stereoisomers of the allene products ensure precise access to the corresponding four stereoisomers of the fluorinated hydrofurans via a novel stereodivergent axial-to-central chirality transfer process. In the experiment, the researchers used many compounds, for example, tert-Butyl (3-ethynylphenyl)carbamate (cas: 185619-66-3Formula: C13H15NO2).

tert-Butyl (3-ethynylphenyl)carbamate (cas: 185619-66-3) 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. 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.Formula: C13H15NO2

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

A new hypercrosslinked supermicroporous polymer, with scope for sulfonation, and its catalytic potential for the efficient synthesis of biodiesel at room temperature was written by Bhunia, Subhajit;Banerjee, Biplab;Bhaumik, Asim. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2015.Application of 106-79-6 This article mentions the following:

A new hypercrosslinked supermicroporous polymer (HMP-1) was designed with a BET surface area of 913 m² g^-1 by FeCl₃ via a catalyzed Friedel-Crafts alkylation reaction between carbazole and α,α’-dibromo-p-xylene. Upon sulfonation HMP-1 yielded a very efficient solid acid catalyst for the production of biodiesels via esterification/transesterification of free fatty acids (FFA)/esters at room temperature In the experiment, the researchers used many compounds, for example, Dimethyl decanedioate (cas: 106-79-6Application of 106-79-6).

Dimethyl decanedioate (cas: 106-79-6) 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. Application of 106-79-6

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

Effects of ultrasound and ultra-high pressure pretreatments on volatile and taste compounds of vacuum-freeze dried strawberry slice was written by Wang, Chao;Zhang, Lihui;Qiao, Yu;Liao, Li;Shi, Defang;Wang, Jun;Shi, Liu. And the article was included in LWT–Food Science and Technology in 2022.Category: esters-buliding-blocks This article mentions the following:

The influences of ultra-high pressure (UHP), ultrasound (US) and their combination (UHP-US) assisted vacuum-freeze drying on volatile and taste compounds of strawberry slices were analyzed by GC-MS, HS-GC-IMS, HPLC, E-tongue as well as sensory anal. Three pretreatments of vacuum-freeze dried strawberry slices could increase the concentrations of characteristic volatile compounds (hexanoates and 2,5-dimethyl-4-methoxy-3(2H)-furanone), especially UHP-US (P < 0.05) sample, the increase of compounds associated with floral, fruity and sweet notes. Meanwhile, these pretreatments would ameliorate the taste of dried strawberry slices, individual sugars (glucose and fructose) increased, while the organic acids (malic acid and citric acid) contents decreased, which was consistent with the result of E-tongue. On the other hand, the taste of US sample was better than other samples, the glucose and fructose content (sweetness) of US sample increased by 19.42%, 23.51%, resp., whereas the malic acid content (sourness) was decreased for 5.03%. All in all, US pretreatment would help to better improve the critical flavors for vacuum-freeze dried strawberry slices. In the experiment, the researchers used many compounds, for example, 5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9Category: esters-buliding-blocks).

5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9) 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. 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.Category: esters-buliding-blocks

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

Mechanical Properties, Melting and Crystallization Behaviors, and Morphology of Carbon Nanotubes/Continuous Carbon Fiber Reinforced Polyethylene Terephthalate Composites was written by Qiao, Liang;Yan, Xu;Tan, Hongsheng;Dong, Shuhua;Ju, Guannan;Shen, Hongwang;Ren, Zhaoying. And the article was included in Polymers (Basel, Switzerland) in 2022.HPLC of Formula: 6683-19-8 This article mentions the following:

Carbon nanotube/continuous carbon fiber reinforced poly(ethylene terephthalate) (CNT/CCF/PET) composites are prepared by melt impregnating. The effects of CF and CNT content on the mech. properties, melt and crystallization behaviors, and submicroscopic morphol. of CNT/CCF/PET composites are studied. The tensile test results show that the increase of CF and the addition of appropriate amount of CNT improved the tensile strength and tensile modulus of the composites. The results of dynamic mech. anal. (DMA) show that the storage modulus of the composites increased with the increase of CF and CNT content. In particular, the addition of CNT greatly reduced the loss modulus of the composites. In addition, there are polymer coated CNT protrusions on the surface of the fiber was observed The results of differential scanning calorimetry (DSC) show that the melting temperature and crystallization temperature of the composites increased with the increase of CF content. The addition of CNT had little effect on the melting temperature of the composites, but it further improved the crystallization temperature of the composites. The effect of CNT content on the crystallization kinetics of the composites is studied. The non-isothermal crystallization kinetics of the composites is described by Jeziorny’s improved Avrami equation. The results show that CNT has a great influence on the crystallization type of the composites. As a nucleating agent, CNT has obvious heterogeneous nucleation effect in the composites, which improves the crystallization rate of PET. In the experiment, the researchers used many compounds, for example, 2,2-Bis(((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoyl)oxy)methyl)propane-1,3-diyl bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate) (cas: 6683-19-8HPLC of Formula: 6683-19-8).

2,2-Bis(((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoyl)oxy)methyl)propane-1,3-diyl bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate) (cas: 6683-19-8) 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. 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.HPLC of Formula: 6683-19-8

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