Tag: M.W=150-200

Padwa, Albert published the artcileEfficient Construction of the Oxatricyclo[6.3.1.00,0]dodecane Core of Komaroviquinone Using a Cyclization/Cycloaddition Cascade of a Rhodium Carbenoid Intermediate, Formula: C9H16O2, the main research area is oxatricyclododecane core komaroviquinone preparation cyclization cycloaddition cascade rhodium carbenoid.

The rhodium(II)-catalyzed cyclization/cycloaddition cascade of a o-carbomethoxyaryl diazo dione is described as a potential route to the oxatricyclo[6.3.1.00,0]dodecane substructure I (R = H, Me) of the icetexane diterpene komaroviquinone. The initially formed carbonyl ylide dipole prefers to cyclize to an epoxide at 25 °C but can be induced to undergo cycloaddition across the tethered π-bond at higher temperatures

Organic Letters published new progress about Cyclization. 86549-27-1 belongs to class esters-buliding-blocks, name is Ethyl 2,2-dimethylpent-4-enoate, and the molecular formula is C9H16O2, Formula: C9H16O2.

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

Padwa, Albert published the artcileA Rh(II)-catalyzed cycloaddition approach toward the synthesis of komaroviquinone, Safety of Ethyl 2,2-dimethylpent-4-enoate, the main research area is komaroviquinone icetexane core synthesis cyclization cycloaddition rhodium catalyzed.

Using a rhodium(II)-catalyzed cyclization/cycloaddition sequence as the key reaction step, the icetexane core of komaroviquinone (I) was constructed by an intramol. dipolar-cycloaddition of a carbonyl ylide dipole across a tethered π-bond. The ylide was arrived at by cyclization of a rhodium carbenoid intermediate onto a proximal ester group. Efforts toward the preparation of the required precursor for elaboration to the natural product are discussed.

Tetrahedron published new progress about Cyclization. 86549-27-1 belongs to class esters-buliding-blocks, name is Ethyl 2,2-dimethylpent-4-enoate, and the molecular formula is C9H16O2, Safety of Ethyl 2,2-dimethylpent-4-enoate.

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

Beckwith, Athelstan L. J. published the artcileReactions of methyl-substituted 5-hexenyl and 4-pentenyl radicals, Category: esters-buliding-blocks, the main research area is hexenyl radical cyclization kinetics; methyl group hexenyl cyclization; pentenyl radical cyclization kinetics.

Relative and absolute kinetic data were determined for cyclization of Me-substituted 5-hexenyl radicals: 2-, 3- and 4-Me- and 2,2-, 3,3- and 4,4-diMe-substituted radicals, generated by interaction of Bu3SnH with the corresponding bromides. Each radical undergoes regiospecific or highly regioselective 1,5-cyclization more rapidly than the unsubstituted radical. The rate enhancements, which arise mainly from lowering of the activation energy, can be rationalized in terms of the gem-di-Me effect. 1,5-Cyclizations of monosubstituted species are stereoselective: 2- and 4-methyl-5-hexenyl radicals give mainly trans products, whereas 3-methyl-4-hexenyl radical gives mainly the cis. This behavior reflects the effect of the substituent on the stabilities of cyclic transition complexes in chair-like conformations. Cyclization of 2,2- or 3,3-dimethyl-4-pentenyl radical could not be detected.

Australian Journal of Chemistry published new progress about Cyclization. 86549-27-1 belongs to class esters-buliding-blocks, name is Ethyl 2,2-dimethylpent-4-enoate, and the molecular formula is C9H16O2, Category: esters-buliding-blocks.

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

Li, Song published the artcileOne-pot hydrodeoxygenation of biomass furan derivatives into decane under mild conditions over Pd/C combined with phosphotungstic acid, Safety of Methyl decanoate, the main research area is furan hydrodeoxygenation decane production palladium carbon combined phosphotungstic acid.

One-pot hydrodeoxygenation (HDO) of biomass furan derivatives into long-chain alkanes remains unclear owing to the complicated reactions at high temperatures Here, Pd/C combined with phosphotungstic acid (HPW), a strong Bronsted solid acid promoter, was developed to produce decane under mild conditions through the one-pot HDO of δ-furfurylidenelevulinic acid (FDLA). A 93.16% sum yield of alkanes including 89.53% yield of decane was obtained under 3 MPa H2 at 170°C for 4 h. The ring-opening and HDO of furans are accomplished at preheating stage, which enable to clarify the complicated reaction pathway. In addition, exptl. validations and catalytic characterizations confirm that the synergistic effect of active acid-metal sites plays a critical role in the generation of alkanes via the formation and hydrogenolysis of lactone intermediates to aldehyde/alc. This work provides guidance for the one-pot HDO of biomass furan derivatives via the combination of metal catalyst and strong Bronsted solid acid under mild conditions.

Green Chemistry published new progress about Deoxidation. 110-42-9 belongs to class esters-buliding-blocks, name is Methyl decanoate, and the molecular formula is C11H22O2, Safety of Methyl decanoate.

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

Zhou, Zi-Wei published the artcileThe Dynamic Change in Fatty Acids during the Postharvest Process of Oolong Tea Production, Application of Methyl decanoate, the main research area is oolong tea linolenic linoleic acid dynamic change; LOX; fatty acids; manufacturing process; oolong tea.

As important factors to oolong tea quality, the accumulation and dynamic change in aroma substances attracts great attention. The volatile composition of oolong tea is closely related to the precursor contents. Fatty acids (FAs) and their derivatives are basic components of oolong tea fragrance during the postharvest process. However, information about the precursors of FAs during the postharvest process of oolong tea production is rare. To investigate the transformation of fatty acids during the process of oolong tea production, gas chromatograph-flame ionization detection (GC-FID) was conducted to analyze the composition of FAs. The results show that the content of total polyunsaturated FAs initially increased and then decreased. Specifically, the contents of α-linolenic acid, linoleic acid and other representative substances decreased after the turn-over process of oolong tea production The results of partial least squares discrimination anal. (PLS-DA) showed that five types of FAs were obviously impacted by the processing methods of oolong tea (VIP > 1.0). LOX (Lipoxygenase, EC 1.13.11.12) is considered one of the key rate-limiting enzymes of long-chain unsaturated FAs in the LOX-HPL (hydroperoxide lyase) pathway, and the mech. wounding occurring during the postharvest process of oolong tea production greatly elevated the activity of LOX.

Molecules published new progress about Leaf. 110-42-9 belongs to class esters-buliding-blocks, name is Methyl decanoate, and the molecular formula is C11H22O2, Application of Methyl decanoate.

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

Petronilho, Silvia published the artcileRevealing the usefulness of aroma networks to explain wine aroma properties: a case study of Portuguese wines, Synthetic Route of 106-32-1, the main research area is Arinto white Bical Baga Castelao wine aroma network; aroma network; aroma sensory analysis; gas chromatography; monovarietal wines; volatile compounds.

Wine aroma is the result of complex interactions between volatile compounds and non-volatile ones and individual perception phenomenon. In this work, an aroma network approach, that links volatile composition (chromatog. data) with its corresponding aroma descriptors was used to explain the wine aroma properties. This concept was applied to six monovarietal wines from Bairrada Appellation (Portugal) and used as a case study. A comprehensive determination of the wines’ volatile composition was done (71 variables, i.e., volatile components), establishing a workflow that combines extraction techniques and gas chromatog. anal. Then, a bipartite network-based approach consisting of two different nodes was built, one with 19 aroma descriptors, and the other with the corresponding volatile compound(s). To construct the aroma networks, the odor active values were calculated for each determined compound and combined with the bipartite network. Finally, the aroma network of each wine was compared with sensory descriptive anal. The anal. of the specific aroma network of each wine revealed that Sauvignon Blanc and Arinto white wines present higher fruity (esters) and sweet notes (esters and C13 norisoprenoids) than Bical wine. Sauvignon Blanc also exhibits higher toasted aromas (thiols) while Arinto and Bical wines exhibit higher flowery (C13 norisoprenoids) and herbaceous notes (thiols), resp. For red wines, sweet fruit aromas are the most abundant, especially for Touriga Nacional. Castelão and Touriga Nacional wines also present toasted aromas (thiols). Baga and Castelão wines also exhibit fusel/alc. notes (alcs.). The proposed approach establishes a chem. aroma fingerprint (aroma ID) for each type of wine, which may be further used to estimate wine aroma characteristics by projection of the volatile composition on the aroma network.

Molecules published new progress about Wine. 106-32-1 belongs to class esters-buliding-blocks, name is Ethyl octanoate, and the molecular formula is C10H20O2, Synthetic Route of 106-32-1.

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

Zhang, Lei published the artcileA reduced reaction mechanism of biodiesel surrogates with low temperature chemistry for multidimensional engine simulation, Product Details of C11H22O2, the main research area is biodiesel surrogate multidimensional engine simulation reduced reaction mechanism.

A reduced biodiesel mechanism composed of 156 species and 589 reactions is reduced from an original complex mechanism (3299 species and 10806 reactions) based on MD, MD9D, and n-heptane as the surrogates. The mechanism reduction is conducted using the path flux anal. method, which considers multiple reaction path generations in the anal. of species interactions, and isomer lumping. These reaction states cover the high-pressure and low-temperature operating conditions of future engines using advanced combustion technologies characterized by fuel-air premixing and auto-ignition. The fidelity of the resulting reduced mechanism with low-temperature chem. is examined using a variety of applications. Close agreements between the reduced and original mechanisms are obtained in the predictions of ignition delay, history of mixture temperature, and species mole fraction during homogeneous auto-ignition and the temperature profile in PSR. The reduced mechanism, further integrated with a nitrogen oxides chem. and a two-step soot model, is implemented into the KIVA/CHEMKIN program for the 3D simulation of biodiesel spray combustion. The predicted liquid and vapor penetrations agree with the exptl. data in a non-reactive biodiesel spray simulation, indicating an accurate estimation of biodiesel phys. properties. In the simulation of biodiesel spray combustion, predicted spatial distributions of hydroxyl radical and soot also agree with the corresponding exptl. data.

Combustion and Flame published new progress about Air. 110-42-9 belongs to class esters-buliding-blocks, name is Methyl decanoate, and the molecular formula is C11H22O2, Product Details of C11H22O2.

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

Gonzalez Viejo, Claudia published the artcileChemical characterization of aromas in beer and their effect on consumers liking, SDS of cas: 106-32-1, the main research area is chem aroma beer; Beer acceptability; Beer aromas; Fermentation; Gas chromatography; Volatiles.

Identification of volatiles in beer is important for consumers acceptability. In this study, triplicates of 24 beers from three types of fermentation (top/bottom/spontaneous) were analyzed using Gas Chromatograph with Mass-Selective Detector (GC-MSD) employing solid-phase microextraction (SPME). Principal components anal. was conducted for each type of fermentation Multiple regression anal., and an artificial neutral network model (ANN) were developed with the peak-areas of 10 volatiles to evaluate/predict aroma, flavor and overall liking. There were no hops-derived volatiles in bottom-fermentation beers, but they were present in top and spontaneous. Top and spontaneous had more volatiles than bottom-fermentation 4-Ethyguaiacol and trans-β-ionone were pos. towards aroma, flavor and overall liking. Styrene had a neg. effect on aroma, flavor and overall liking. An ANN model with high accuracy (R = 0.98) was obtained to predict aroma, flavor and overall liking. The use of SPME-GC-MSD is an effective method to detect volatiles in beers that contribute to acceptability.

Food Chemistry published new progress about Ale. 106-32-1 belongs to class esters-buliding-blocks, name is Ethyl octanoate, and the molecular formula is C10H20O2, SDS of cas: 106-32-1.

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

Deng, Yang published the artcileComposition and biochemical properties of ale beer enriched with lignans from Schisandra chinensis Baillon (omija) fruits, Product Details of C10H20O2, the main research area is Schisandra ale beer schisandrin gomisin phenol viscosity oxidative stability; Antioxidant capacity; Beer; Lignans; Schisandra chinensis; Sensory characteristics.

To develop a beverage with high antioxidant capacity and desirable sensory characteristics, Schisandra chinensis (omija) fruits were added to ale type beer at different time points of the brewing process. The phenolic compounds contents in beer were found to be dependent at the moment of the addition of omija fruit. Addition of omija fruits at the initiation of boiling imparted highest oxidative stability to beer and resulted in highest total phenolic and flavonoid contents in ale beer (606.82 mg GAE/L and 406.75 mg QE/L, resp.). The amounts of schisandrin, gomisin A and gomisin B in beer were 12.10 mg/mL, 3.12 mg/mL and 0.86 mg/mL, resp. Taken together, it is hypothesized that the addition of omija fruits to traditional brewing process can improve the development of value-added beer products.

Food Science and Biotechnology published new progress about Ale. 106-32-1 belongs to class esters-buliding-blocks, name is Ethyl octanoate, and the molecular formula is C10H20O2, Product Details of C10H20O2.

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

Ishiguro, Takako published the artcileThe use of enteric capsules for releasing a fragrance over an extended period of time, Related Products of esters-buliding-blocks, the main research area is hypro mellose acetate succinate enteric capsule releasing fragrance; delayed release; enteric capsule; fragrance; pH adjustment; time lag.

A system for releasing a fragrance, citral (CR) over an extended period of time using three types of enteric capsules is reported. The L- and M-type capsules released CR into media with a pH above 6, while the H-type capsule released CR at a pH above 7. The pH of the releasing medium was controlled by sodium borate (SB), i.e., by adding SB-methylcellulose (MC) prepared in different weight ratios (SB-MC 1 : 2, 1 : 1 and 2 : 1) to tablets and by compressing them at different pressures. The tablet containing a large amount of SB and that was pressed at higher pressures permitted the pH of the releasing medium to be changed from 5 to 9, at 4-5 h after the addition of SB to the tablets, while negligible changes were observed for tablets containing low amounts of SB and which were compressed at lower pressures. Reflecting these pH changes, CR was released after different periods of time when SB-MC tablets and capsules containing CR were simultaneously added to the releasing medium. When enteric capsules containing CR and the pH adjusting tablets were simultaneously added to a benzyl acetate (BA) solution, BA was released at a constant rate, while CR was released for different periods of time depending on the type of capsule used. The results suggest that fragrances could be released over different time frames by using enteric capsules and pH adjusting agents, for example, the release of fragrances with sedative effects at night time and with stimulating effects in the morning.

Chemical & Pharmaceutical Bulletin published new progress about pH. 140-11-4 belongs to class esters-buliding-blocks, name is Benzyl acetate, and the molecular formula is C9H10O2, Related Products of esters-buliding-blocks.

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