Tag: 100-200

Highly efficient [2 + 2] intramolecular cyclizations of allenynes under microwave irradiation: construction of fused bicyclic compounds was written by Oh, Chang Ho;Gupta, Arun Kumar;Park, Dai In;Kim, Nakjoong. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2005.Quality Control of Diethyl 2-(prop-2-yn-1-yl)malonate This article mentions the following:

A palladium [2 + 2] cycloaddition of 1,6- and 1,7- allenyne carboxylates and microwave-mediated [2 + 2] cycloaddition of various 1,n-allenynes were developed and, particularly, the microwave irradiated [2 + 2] cycloaddition of allenynes can provide a simple, general and eco-friendly synthetic method to fused bicyclo[m,2,0]alkadienes. E.g., microwave irradiation of allenyne CH₂:C:CHCH₂N(Ts)CH₂CCCO₂Et gave 89% bicyclo[m,2,0]alkadiene I. In the experiment, the researchers used many compounds, for example, Diethyl 2-(prop-2-yn-1-yl)malonate (cas: 17920-23-9Quality Control of Diethyl 2-(prop-2-yn-1-yl)malonate).

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

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

Volatile components of Borassus aethiopum was written by Mahmout, Yaya;Mbaiguinam, Mbailao;Bessiere, Jean-Marie. And the article was included in Journal de la Societe Ouest-Africaine de Chimie in 2001.Recommanded Product: Ethyl 2-hydroxy-3-phenylpropanoate This article mentions the following:

The essential oil and the methylene chloride extract of the pulp of B. aethiopum of Chad were analyzed. The essential yield of the samples was 0.5-0.7%, while methylene chloride extracts gave 1.3% of the residue. The essential oil was characterized by (E)-Et cinnamate and geranylacetone (10.5%) with lesser amounts of 3-phenylpropanol (8.6%) and farnesylacetone (5%). The other main esters were Et 3-hydroxybutanoate (3.4%), Et 3-phenylpropanoate (2.7%), Et benzoate (1.7%), (E)-Me cinnamate (0.8%), Et 3-hydroxyisohexanoate (0.6%) and phenylethyl tiglate (0.6%). The richness of ester compounds may have contributed significantly to the pleasant odor of the ripe fruits of B. aethiopum. The presence of (E)-Et cinnamate in the oil of B. aethiopum was the most major difference noticed on comparison of the essential oil of samples from Sudan. Most of the identified components were not previously known to be present in the volatile extracts of B. aethiopum. These compositional differences may be chemotaxonomically significant. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxy-3-phenylpropanoate (cas: 15399-05-0Recommanded Product: Ethyl 2-hydroxy-3-phenylpropanoate).

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

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

Facile synthesis of δ-ketoesters via formal two-carbon insertion into β-ketoesters was written by Jiang, Yan;Xi, Song;Wang, Qi;Fu, Lin;He, Ling;Wang, Zhen;Zhang, Min. And the article was included in Tetrahedron Letters in 2022.Category: esters-buliding-blocks This article mentions the following:

A formal two-carbon insertion into β-ketoesters with vinylmetal has been developed for the rapid synthesis of δ-ketoesters. This method features high efficiency, simple operation, and mild conditions without the usage of bases and catalysts. The reaction is postulated to proceed via a tandem process in volving nucleophilic addition of vinylmetal to ketone, retro-aldol reaction to give an enolate anion and an enone, and finally Michael addition of these two intermediates. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8Category: esters-buliding-blocks).

Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8) 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. 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.Category: esters-buliding-blocks

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

The carboxyl group. Infrared absorption and ionization was written by Peltier, Daniel;Pichevin, Annick. And the article was included in Bulletin de la Societe Chimique de France in 1960.Application of 81245-24-1 This article mentions the following:

PK, ν_OH(monomeric), and ν_C:O (monomeric and dimeric) values of 17 substituted benzoic, 34 o-toluic, 17 m-toluic, and 12 p-toluic acids, as well as the ν_C:O values of 55 Me and Et esters were tabulated. For all the acids except the 6-substituted o-toluic acids (6-NO₂, I, Br, Cl, OH, NH₂), ν_OH (cm.^-1) = 3498 + 9pK. The ν_C:O (monomeric) of the o-OH and o-NH₂ acids were on the average 55 cm.^-1 lower and those of nonchelated, 6-substituted o-toluic acids were approx. 5 cm.^-1 higher than calculated from the appropriate equations (CA 53, 17954e). For acids free of chelation and steric effects, ν_OH = 5,028 – 0.857 ν_C:O (monomeric) (cm.^-1). For 3-, 4-, and 5-substituted o-toluic acids, ν_OH = 5053 – 0.874 ν_C:O. The carbonyl frequencies of the Et esters were approx. 5 cm.^-1 lower than those of the corresponding Me esters. These results are explained by electronic effects of H or alkyl group on the carbonyl group. 6-HO(or H₂N)-2-MeC₆H₃CO₂Me exhibited 2 carbonyl frequencies related to chelated and nonchelated forms. Similar data were presented for 2,3- (I), 2,4-, and 2,6-(MeO)MeC₆H₃CO₂H, and o-MeOC₆H₄CO₂H. The dimeric carbonyl absorptions were weak, the ν_OH were lower, and the ν_C:O were higher, based on the relations with pK, than expected for nonchelated acids. I was exceptional, as it gave a strong dimeric carbonyl absorption. In the experiment, the researchers used many compounds, for example, Methyl 2-methoxy-4-methylbenzoate (cas: 81245-24-1Application of 81245-24-1).

Methyl 2-methoxy-4-methylbenzoate (cas: 81245-24-1) 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. 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 81245-24-1

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

Photolactonization: a novel synthetic entry to macrolides was written by Quinkert, Gerhard;Billhardt, Uta Maria;Jakob, Harald;Fischer, Gerd;Glenneberg, Juergen;Nagler, Peter;Autze, Volker;Heim, Nana;Wacker, Manfred. And the article was included in Helvetica Chimica Acta in 1987.COA of Formula: C11H14O3 This article mentions the following:

o-Quinol acetates, hydroxyalkylated at C-6 (e.g., I), are easily accessible from simple phenols by Wessely acetoxylation (preferentially catalyzed by BF₃). On UV irradiation (in the presence of an appropriate tertiary amine), they are smoothly converted to macrocyclic lactones, e.g., II. Subtle conditions were elaborated to lead to high overall yields, and the scope of the conversion of phenols to macrolides was elucidated. In the experiment, the researchers used many compounds, for example, Methyl 4-(2-hydroxyphenyl)butanoate (cas: 93108-07-7COA of Formula: C11H14O3).

Methyl 4-(2-hydroxyphenyl)butanoate (cas: 93108-07-7) 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. 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.COA of Formula: C11H14O3

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

Volatile compositions of strawberry fruit during shelf life using pre and postharvest hexanal treatment was written by Oz, Ayse Tuelin;Kafkas, Ebru. And the article was included in Journal of Food Processing and Preservation in 2022.Product Details of 706-14-9 This article mentions the following:

Changes in volatile compositions were determined in Rubygem strawberry variety related to pre and postharvest hexanal application during shelf life. For this concern, Rubygem variety was treated with hexanal vapor and spray applications which were, doses (0%, 0.01%, 0.02%) pre and postharvest after hexanal applications strawberry fruits were stored at 2°C and RH 90% conditions. Effects of hexanal spray and vapor applications of strawberry fruit volatile profiles were analyzed with HS-SPME/GC-MS techniques. Differences among treatments were identified in volatile compositions at 3 days intervals during 15 days of shelf life. The results showed that, hexanal application type and concentration effected the percentage of volatile composition of esters, ketones, terpens, alcs., acids, aldehydes, and others during shelf life. The hexanal application form and concentration were effected the amount and composition of volatiles of Rubygem strawberry fruit. As a result, hexanal spray application has important effects on ester percentage, however, hexanal vapor treatment increased the alcs. percentage of strawberries at the end of shelf life. Practical applications : Application of organic substances of hexanal pre and postharvest season has been successfully used due to their environmentally friendly effects. Hexanal is volatile gases, organic aldehydes which are the source of plant extract and used as food additives. There are many research on hexanal application to prevent microbial growth after harvest. In the present study, hexanal spray and vapor applications were used to determined the volatiles profile strawberries fruit during shelf life. 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. 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. 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.Product Details of 706-14-9

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

GC-MS analysis of e-cigarette refill solutions: A comparison of flavoring composition between flavor categories was written by Krusemann, Erna J. Z.;Pennings, Jeroen L. A.;Cremers, Johannes W. J. M.;Bakker, Frank;Boesveldt, Sanne;Talhout, Reinskje. And the article was included in Journal of Pharmaceutical and Biomedical Analysis in 2020.Related Products of 659-70-1 This article mentions the following:

Electronic cigarette refill solutions (e-liquids) are available in various flavor descriptions that can be categorized as fruit, tobacco, and more. Flavors increase sensory appeal, thereby stimulating e-cigarette use, and flavoring ingredients can contribute to e-cigarette toxicity. We aim to inform toxicologists, sensory scientists, and regulators by determining flavoring compounds in e-liquids with various flavors, and compare results between flavor categories. Gas chromatog.-mass spectrometry (GC-MS) was used to identify 79 flavorings in 320 e-liquids, classified in 15 flavor categories. Ten flavorings highly prevalent in e-liquids according to information from manufacturers were quantified. Flavoring prevalence was defined as the number of e-liquids with the flavoring as percentage of the total number of e-liquids The method was validated in terms of specificity, linearity, repeatability, recovery, and sensitivity. The mean number of flavorings per e-liquid was 6 ± 4. Flavoring prevalence was highest for vanillin (creamy/vanilla flavor), Et butyrate (ethereal/fruity), and cis-3-hexenol (fresh/green). Based on similarities in flavoring prevalence, four clusters of categories were distinguished: (1) fruit, candy, alc., beverages; (2) dessert, coffee/tea, nuts, sweets; (3) menthol/mint; and (4) spices, tobacco, and unflavored. Categories from cluster 4 generally had less flavorings per e-liquid than fruit, candy, alc., beverages (cluster 1) and dessert (cluster 2) (p < 0.05). Flavoring concentrations varied between e-liquids within the categories. We evaluated flavoring compositions of 320 e-liquids using a simple GC-MS method. Flavoring prevalence was similar within four clusters of typically fresh/sweet, warm/sweet, fresh/cooling, and non-sweet flavor categories. To compare flavoring concentrations between individual flavor categories, addnl. research is needed. In the experiment, the researchers used many compounds, for example, Isopentyl 3-methylbutanoate (cas: 659-70-1Related Products of 659-70-1).

Isopentyl 3-methylbutanoate (cas: 659-70-1) 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.Related Products of 659-70-1

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

Decarboxylative Mannich Reactions with Substituted Malonic Acid Half-Oxyesters was written by Xavier, Tania;Condon, Sylvie;Pichon, Christophe;Le Gall, Erwan;Presset, Marc. And the article was included in Journal of Organic Chemistry in 2021.SDS of cas: 17920-23-9 This article mentions the following:

The decarboxylative Mannich reaction between imines and substituted malonic acids half-oxyesters (SMAHOs) has been developed using 1,4-diazabicyclo[2.2.2]octane (DABCO) as an organocatalyst. The reaction proceeds under simple reaction conditions and tolerates a broad range of substrates, affording general access to β²,³-aminoesters, the syn diastereomer being the major one. An alternative multicomponent protocol has also been developed to increase the overall eco-compatibility of the process. In the experiment, the researchers used many compounds, for example, Diethyl 2-(prop-2-yn-1-yl)malonate (cas: 17920-23-9SDS of cas: 17920-23-9).

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

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

Fast pyrolysis of fermentation residue derived from Saccharina japonica for a hybrid biological and thermal process was written by Choi, Jae Hyung;Kim, Seung-Soo;Kim, Jinsoo;Woo, Hee Chul. And the article was included in Energy (Oxford, United Kingdom) in 2019.Safety of Methyl2-methylbutyrate This article mentions the following:

Pyrolysis characteristics of Saccharina japonica fermentation residue (SJFR) were systematically investigated using a thermogravimetric analyzer and a bubbling fluidized-bed reactor. Thermogravimetric (TG) characteristics of the SJFRs with increasing fermentation time (1-6 day) showed a decrease of second peak related to fermentable carbohydrates (e.g., alginate and fucoidan) and an increase of third peak related to non-fermentable carbon sources. The calculated apparent activation energy of the SJFRs ranged from 20.21 to 295.46 kJ/mol, depending on the conversion rate of 5-80%. Between 10 and 40% conversion at 225-310°C, the apparent activation energies of the SJFRs on each conversion decreased with increasing the fermentation time (1-6 day). The bubbling fluidized-bed pyrolysis of the SJFR-4D and -6D showed the high bio-oil yield of 39.86 and 40.12 wt%, resp. at 375°C and 4.0 × U_mf, and the HHVs of the organic bio-oils were 28.95-29.34 MJ/kg. The characteristics of the bio-oil derived from SJFRs were analyzed by GC-MS and the TG-based simulated distillation The fractions of gas oil and heavy gas oil were increased, whereas the one of gasoline decreased with increasing fermentation time. It is attributed to a decrease of the fermented carbohydrates (e.g., alginate and fucoidan) related to the gasoline fraction. In the experiment, the researchers used many compounds, for example, Methyl2-methylbutyrate (cas: 868-57-5Safety of Methyl2-methylbutyrate).

Methyl2-methylbutyrate (cas: 868-57-5) 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. 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 Methyl2-methylbutyrate

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

Assessment of fresh Alpinia galanga (A. galanga) drying techniques for the chemical composition of essential oil and its antioxidant and biological activity was written by Ge, Xiangzhen;Liang, Qiuhong;Long, Yao;Shen, Huishan;Zhang, Qian;Sun, Zhuangzhuang;Li, Wenhao. And the article was included in Food Chemistry in 2022.Category: esters-buliding-blocks This article mentions the following:

This study evaluated drying characteristics, structure and essential oil chem. composition, and biol. activity of A. galanga by hot air drying (HAD), vacuum drying (VD), freeze drying (FD). The results showed that HAD had the shortest drying time while FD could better maintain the microstructure and showed a higher essential oil yield than HAD and VD. In addition, E-nose, HS-GC-IMS and HS-SPME-GC-MS could effectively distinguish the essential oil chem. composition of the four samples because different drying methods induced the changes in the profile and content of the compounds HS-SPME-GC-MS detected 43 compounds, of which alcs., alkenes, and esters were the main substances in fresh and dry samples. In comparison, HS-SPME-GC-IMS detected 80 compounds, including alcs., aldehydes, ketones, esters, alkenes. Overall, the FD samples showed more outstanding advantages by evaluating antioxidant properties and antibacterial activities. FD was more suitable for A. galanga drying as it maintains appearance and biol. activity. In the experiment, the researchers used many compounds, for example, (E)-3,7-Dimethylocta-2,6-dien-1-yl acetate (cas: 105-87-3Category: esters-buliding-blocks).

(E)-3,7-Dimethylocta-2,6-dien-1-yl acetate (cas: 105-87-3) 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. 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.Category: esters-buliding-blocks

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