Tag: M.W=150-200

Pospelova, Violetta published the artcileDoes the structure of CuZn hydroxycarbonate precursors affect the intrinsic hydrogenolysis activity of CuZn catalysts?, Category: esters-buliding-blocks, the publication is Catalysis Science & Technology (2020), 10(10), 3303-3314, database is CAplus.

A comparative study of the properties and hydrogenolysis activity of catalysts derived from single-phase CuZn precursors was carried out to elucidate the effect of the precursor structure on the catalyst activity in hydrogenolysis and to examine their potential to replace the classical CuCr catalysts. Three CuZn catalysts were prepared by co-precipitation aiming at Cu/Zn ratios of 0.7, 5.0 and 1.6 to obtain single-phase aurichalcite, zincian malachite and a mixture of both phases, resp. The catalyst precursors were calcined at temperatures of 300 and 450°, reduced in situ and tested in di-Me adipate hydrogenolysis. The properties of the precursors and catalysts were analyzed using in situ XRD, TGA-MS, TPR-H₂, N physisorption and N₂O chemisorption methods. Data, aurichalcite-derived catalysts had superior structural properties to zincian malachite-derived catalysts: smaller Cu crystallites, larger total and Cu surface areas, and stable surface areas during the experiment Consequently, aurichalcite-derived catalysts outperformed catalysts prepared from zincian malachite in the studied range of phase and elemental CuZn compositions The calculated intrinsic hydrogenolysis activity of surface Cu sites (TOF) was similar for all 3 catalysts.

Catalysis Science & Technology published new progress about 627-93-0. 627-93-0 belongs to esters-buliding-blocks, auxiliary class Ploymers, name is Dimethyl adipate, and the molecular formula is C8H14O4, Category: esters-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Pospelova, Violetta published the artcileTowards efficient Cu/ZnO catalysts for ester hydrogenolysis: The role of synthesis method, Category: esters-buliding-blocks, the publication is Applied Catalysis, A: General (2021), 118320, database is CAplus.

Cu/ZnO catalysts represent an environmentally friendly alternative to Adkins catalysts used for ester hydrogenolysis. Cu/ZnO are mostly synthesized by co-precipitation (COP); however, other synthesis methods may help to obtain small highly dispersed Cu crystallites advantageous for catalyst activity. A comparative study on the effect of synthesis method on Cu/ZnO catalysts properties and activity is missing. Thus, the authors synthesized 8% Cu/ZnO catalysts by 5 methods (COP, deposition-precipitation (DP), chemisorption-hydrolysis (CH), incipient wetness (IWI) and wet impregnation (WI)), characterized and tested them in di-Me adipate hydrogenolysis. The CH-prepared catalyst was prone to Cu sintering, which impaired its performance. IWI led to large Cu nanoparticles, pore blocking and poor catalytic performance. COP and DP resulted in the smallest Cu nanoparticles (13-14 nm), largest Cu surface area (3.9-4.2 m² g^-1_cat) and sp. surface area (40-43 m² g^-1_cat) reflected in their superior catalytic activity making DP a good alternative to COP to prepare active Cu/ZnO catalysts.

Applied Catalysis, A: General published new progress about 627-93-0. 627-93-0 belongs to esters-buliding-blocks, auxiliary class Ploymers, name is Dimethyl adipate, and the molecular formula is C8H14O4, Category: esters-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Bohre, Ashish published the artcileSingle-Step Production of Bio-Based Methyl Methacrylate from Biomass-Derived Organic Acids Using Solid Catalyst Material for Cascade Decarboxylation-Esterification Reactions, Application In Synthesis of 617-52-7, the publication is ACS Sustainable Chemistry & Engineering (2021), 9(7), 2902-2911, database is CAplus.

This study shows the direct chem. conversion of a widely available carbohydrate-derived itaconic acid/methanol into the Me methacrylate (MMA) ester via cascade decarboxylation/esterification reactions has been accomplished as a first-time occurrence over solid catalysts. The state-of-the-art Pt/Al₂O₃ catalytic processing displayed an optimum MMA compound selectivity (38.2 mol %) in the presence of an aqueous solution mixture with an alk. base substance. To eliminate issues associated with the utilization of precious-metal materials, corrosive water-dissolved hydroxides, and deactivation, hexaaluminate was introduced for active stable decomposition in the production of MMA. Since defined acidic/basic sites are necessary to promote intermediates, barium hexaaluminate, calcium hexaaluminate and lanthanum hexaaluminate were prepared by tuning their phys. properties. To shed light on reactivity, the catalysts were characterized by extensive microscopic and spectroscopic techniques. Barium hexaaluminate (BHA) was found to have the highest turnover frequency (TOF) among all tested values. Detailed exptl./structural investigations indicated that a medium-strength Bronsted/weak Lewis boundary along with peculiar layered structure, surface defects, and characteristic area are strongly correlated with the activity/stability of BHA. A plausible elementary mechanism for this step transformation was also hypothesized, detailing protonated surface-bonded reactive precursor species.

ACS Sustainable Chemistry & Engineering published new progress about 617-52-7. 617-52-7 belongs to esters-buliding-blocks, auxiliary class Alkenyl,Aliphatic hydrocarbon chain,Ester, name is Dimethyl itaconate, and the molecular formula is C7H10O4, Application In Synthesis of 617-52-7.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Bampidis, Vasileios published the artcileSafety and efficacy of a feed additive consisting of an essential oil from the flowers of Cananga odorata (Lam.) Hook.f. & Thomson (ylang ylang oil) for use in all animal species (FEFANA asbl), Quality Control of 5205-11-8, the publication is EFSA Journal (2022), 20(2), e07159, database is CAplus and MEDLINE.

Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of an essential oil from the flowers of Cananga odorata (Lam.) Hook.f. & Thomson (ylang ylang oil), when used as a sensory additive in feed and water for drinking for all animal species. The FEEDAP Panel concluded that the essential oil under assessment is safe up to the maximum proposed use levels in complete feed of 1 mg/kg for chickens for fattening, 1.5 mg/kg for laying hens, turkeys for fattening and rabbits, 2 mg/kg for piglets, 2.5 mg/kg for pigs for fattening, 3 mg/kg for sows, 4.5 mg/kg for cattle for fattening, sheep, goats and horses, 5 mg/kg for veal calves (milk replacer), fish, dogs and ornamental fish. For cats, the calculated safe concentration in complete feed is 1 mg/kg feed. The FEEDAP Panel considered that the use in water for drinking is safe provided that the total daily intake of the additive does not exceed the daily amount that is considered safe when consumed via feed. No concerns for consumer safety were identified following the use of the additive up to the maximum proposed use level in feed. The essential oil under assessment should be considered as irritant to skin and eyes, and as a skin and respiratory sensitizer. The use of the additive in animal feed under the proposed conditions of use was not expected to pose a risk for the environment. Ylang ylang oil is recognized to flavor food. Since its function in feed would be essentially the same as that in food, no further demonstration of efficacy is considered necessary.

EFSA Journal published new progress about 5205-11-8. 5205-11-8 belongs to esters-buliding-blocks, auxiliary class Alkenyl,Benzene,Ester, name is 3-Methylbut-2-en-1-yl benzoate, and the molecular formula is C12H14O2, Quality Control of 5205-11-8.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Noji, Masahiro published the artcileProton-accelerated Lewis acid catalysis for stereo- and regioselective isomerization of epoxides to allylic alcohols, Recommanded Product: 3-Methylbut-2-en-1-yl benzoate, the publication is Chemical Communications (Cambridge, United Kingdom) (2021), 57(58), 7104-7107, database is CAplus and MEDLINE.

The isomerization of epoxides to allylic alcs. was developed via proton-accelerated Lewis acid catalysis. The addition of tBuOH as a proton source was the key to the efficient catalytic cycle. Trisubstituted epoxides, including enantioenriched derivatives, were selectively converted to secondary-allylic alcs. without loss of enantiopurity.

Chemical Communications (Cambridge, United Kingdom) published new progress about 5205-11-8. 5205-11-8 belongs to esters-buliding-blocks, auxiliary class Alkenyl,Benzene,Ester, name is 3-Methylbut-2-en-1-yl benzoate, and the molecular formula is C12H14O2, Recommanded Product: 3-Methylbut-2-en-1-yl benzoate.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Bosch, Joan published the artcileStereoselective Syntheses of the Antihistaminic Drug Olopatadine and Its E-Isomer, Application of Methyl 2-(3-formyl-4-hydroxyphenyl)acetate, the publication is Journal of Organic Chemistry (2012), 77(14), 6340-6344, database is CAplus and MEDLINE.

Practical stereoselective synthetic routes to the antihistaminic drug olopatadine (I) and its E-isomer have been developed, the key steps being a trans stereoselective Wittig olefination using a nonstabilized phosphorus ylide and a stereoselective Heck cyclization. The stereoselectivity of the Wittig reaction depends on both the phosphonium salt anion and the cation present in the base used to generate the ylide.

Journal of Organic Chemistry published new progress about 61874-04-2. 61874-04-2 belongs to esters-buliding-blocks, auxiliary class Benzene,Phenol,Ester,Aldehyde, name is Methyl 2-(3-formyl-4-hydroxyphenyl)acetate, and the molecular formula is C10H10O4, Application of Methyl 2-(3-formyl-4-hydroxyphenyl)acetate.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Ucar, Guenes published the artcileVolatile needle and wood extracts of oriental spruce Picea orientalis (L.) Link, COA of Formula: C12H14O2, the publication is Flavour and Fragrance Journal (2003), 18(5), 368-375, database is CAplus.

Volatile needle and wood extracts of oriental spruce obtained from trees grown naturally in eastern Black Sea regions and in an cultivated stand near Istanbul were analyzed by GC-MS. Despite considerable differences in both tree-to-tree and natural-to-cultivated aspects, the needle and wood extracts exhibit characteristic compounds, which might be of chemotaxonomic interest. The monoterpenes δ-3-carene, limonene and bornyl acetate dominate in the needles, whereas the appreciable amounts of labdadienol isomers and high content of diterpenoids characterize the wood extracts

Flavour and Fragrance Journal published new progress about 5205-11-8. 5205-11-8 belongs to esters-buliding-blocks, auxiliary class Alkenyl,Benzene,Ester, name is 3-Methylbut-2-en-1-yl benzoate, and the molecular formula is C10H15NO, COA of Formula: C12H14O2.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Chen, Gong published the artcileDirhodium-Catalyzed Chemo- and Site-Selective C-H Amidation of N,N-Dialkylanilines, Safety of Ethyl 4-dimethylaminobenzoate, the publication is Synlett (2021), 32(7), 728-732, database is CAplus.

A method for dirhodium-catalyzed C(sp³)-H amidation of N,N-dimethylanilines was developed. Chemoselective C(sp³)^–H amidation of N-Me group proceeded exclusively in the presence of C(sp²)-H bonds of the electron-rich aromatic ring. Site-selective C(sp³)-H amidation proceeded exclusively at the N-Me group of N-methyl-N-alkylaniline derivatives with secondary, tertiary, and benzylic C(sp³)-H bonds α to a nitrogen atom.

Synlett published new progress about 10287-53-3. 10287-53-3 belongs to esters-buliding-blocks, auxiliary class Amine,Benzene,Ester, name is Ethyl 4-dimethylaminobenzoate, and the molecular formula is C11H15NO2, Safety of Ethyl 4-dimethylaminobenzoate.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Celeiro, Maria published the artcileEvaluation of chemicals of environmental concern in crumb rubber and water leachates from several types of synthetic turf football pitches, Application of Dimethyl adipate, the publication is Chemosphere (2021), 128610, database is CAplus and MEDLINE.

Nowadays concern exists about the safety for both football players and the environment of recycled tire rubber used as infill in synthetic turf football pitches. In this study 40 target compounds, including polycyclic aromatic hydrocarbons (PAHs), plasticizers, antioxidants and vulcanization agents were determined in 50 synthetic football pitches of diverse characteristics to estimate environmental risks. This is the first study of crumb rubber sport facilities in Portugal. Analyses were performed by ultrasound-assisted extraction followed by gas chromatog.-tandem mass spectrometry (UAE-GC-MS/MS). To evaluate the transfer of the target chems. from the crumb rubber to the runoff water, water leachates collected from several football pitches were analyzed by solid-phase microextraction (SPME-GC-MS/MS). In addition, lab-scale runoff simulation experiments were performed to assess whether a persistent inflow of the target compounds from the football pitches into the runoff water wcould exist. Results revealed the presence of most of the target PAHs in crumb rubber at total concentrations up to 57μg g-1, next to a high number of plasticizers and vulcanization agents. Runoff water collected from the football pitches contained up to 13 PAHs as well as other chems. of environmental concern. In addition, continuous leaching of chems. from the crumb rubber to the surrounding water was demonstrated. The transfer of target chems. into the runoff water poses a potential risk for the aquatic environment.

Chemosphere published new progress about 627-93-0. 627-93-0 belongs to esters-buliding-blocks, auxiliary class Ploymers, name is Dimethyl adipate, and the molecular formula is C8H14O4, Application of Dimethyl adipate.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Celeiro, Maria published the artcileHazardous compounds in recreational and urban recycled surfaces made from crumb rubber. Compliance with current regulation and future perspectives, Quality Control of 627-93-0, the publication is Science of the Total Environment (2021), 755(Part_1), 142566, database is CAplus and MEDLINE.

Crumb rubber obtained from scrap tires is greatly employed for the construction of different facilities for sport, recreational and other uses. However, in recent years the concern about their safety and the related adult and children exposure to these surfaces is growing. This study aims a thorough chem. characterization encompassing 42 hazardous compounds, including polycyclic aromatic hydrocarbons (PAHs), phthalates, adipates, antioxidants and vulcanization agents in a wide range of crumb rubber from different surfaces. For the extraction of the target compounds, a method based on ultrasound-assisted extraction followed by gas chromatog.-tandem mass spectrometry (UAE-GC-MS/MS) was validated. Forty crumb rubber samples coming from synthetic turf football pitches, outdoor and indoor playgrounds, urban pavements, com. tiles and granulates, and scrap tires, were analyzed. In addition, green alternative materials, such as sand and artificial turf based on cork granulate infill were included to compare the levels of the target compounds with those of crumb rubber. Most of the analyzed recycled surfaces meet the recent limits proposed by the European Commission for rubber granulates and mulches, although they exceed in several cases the maximum levels allowed for rubber consumer products. Besides, most of the other target compounds, including several of them considered as endocrine disruptors, were detected in the analyzed samples, reaching ppm concentrations

Science of the Total Environment published new progress about 627-93-0. 627-93-0 belongs to esters-buliding-blocks, auxiliary class Ploymers, name is Dimethyl adipate, and the molecular formula is C8H14O4, Quality Control of 627-93-0.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics