Tag: M.W=100-150

Giacomin, Wanderson R. Jr. published the artcilePhase Equilibrium Measurements and Thermodynamic Modeling of the Systems (CO2 + Ethyl Levulinate) and (CO2 + Levulinic Acid), Quality Control of 539-88-8, the main research area is phase equilibrium thermodn model system carbon dioxide ethyl levulinate.

This work reports phase equilibrium measurements and thermodn. modeling of the binary systems (CO2 + Et levulinate) and (CO2 + levulinic acid). Each composition was carried out in a high-pressure variable-volume view cell at temperatures ranging from 303.15 to 353.15 K and with CO2 mole fraction ranging from 0.4002 to 0.9751 for the system (CO2 + Et levulinate) and from 0.4083 to 0.9930 for the system (CO2 + levulinic acid). Under these conditions, only vapor-liquid phase transitions were observed The exptl. data were modeled with the Peng-Robinson cubic equation of state with the Boston-Mathias alpha function (PR-BM) and using the van der Waals quadratic mixing rule. The exptl. data of the system (CO2 + Et levulinate) were adequately represented by the thermodn. model with a unique set of binary interaction parameters, which were fitted from all isotherms. Whereas the exptl. data of the system (CO2 + levulinic acid) were only adequately represented with temperature-dependent binary interaction parameters.

Journal of Chemical & Engineering Data published new progress about Binary phase diagram. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Quality Control of 539-88-8.

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

Dutta, Saikat published the artcileRecent Advances in the Value Addition of Biomass-Derived Levulinic Acid: A Review Focusing on its Chemical Reactivity Patterns, SDS of cas: 539-88-8, the main research area is review levulinic acid biomass chem reaction.

Levulinic acid (LA) is one of the most prominent biomass-derived chem. building blocks that can be transformed into specialty chems. like fuels, solvents, monomers for polymers, plasticizers, surfactants, agrochems., and pharmaceuticals. Over the past three decades, an enormous amount of research data have been acquired on the preparation and downstream value addition of LA, and these works have been reviewed. However, considering the astonishing number of publications appearing every year on LA derivatives, the periodical review of recent works focusing on unique aspects of chem. must be undertaken to critically evaluate the achievements to date, reassess the challenges, and recognize new opportunities. This review discusses the chem.-catalytic synthesis of various derivatives of LA by focusing on its functionalities and reactivity patterns. Recent literature on some crucial derivatives such as γ-valerolactone, 4,4-diphenolic acid, and Et levulinate have been tabulated and discussed. The synthetic interconversion between various derivatives, mechanistic insights, critical anal. of the reaction parameters toward selective preparation of various derivatives, and their potential com. applications have been elaborated using predominantly heterogeneous catalysts. A critical assessment of the relative advantages and shortcomings of the existing synthetic strategies for various derivatives of LA has been presented to enkindle fresh ideas.

ChemCatChem published new progress about Biochemical reaction. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, SDS of cas: 539-88-8.

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

Chen, Cheng published the artcileAsymmetric reduction of 2-chloro-3-oxo-ester into enantiomerically high pure diltiazem precursor by a Candida ketoreductase, Application In Synthesis of 5405-41-4, the main research area is Candida ketoreductase asym reduction oxoester chiral synthon diltiazem.

Me (2R,3S)-3-(4-methoxyphenyl)glycidate [(2R,3S)-MPGM] is an advanced chiral synthon for the synthesis of the cardiovascular drug diltiazem. It can be easily accessed by cyclizing the reduction products of Me 2-chloro-3-(4-methoxyphenyl)-3-oxo-propanoate. Herein, we report an identified carbonyl reductase (CpKR) from Candida parapsilosis that displayed an excellent stereoselectivity toward the keto substituent at the C3-position of the 2-chloro-3-oxo-ester. The engineered Escherichia coli cells harboring CpKR gene were directly applied for the asym. reduction of keto ester 1a with a space-time yield of 46 g L-1 d-1, which represents the highest productivity in bio-reduction reported so far. The isolated chiral alc. products were then applied to the chem. synthesis of (2R,3S)-MPGM in 99% ee and a total yield of 76% in the two-step chemo-enzymic reactions, which far exceeded the maximum theor. yield (50%) of the existing industrial process based on a lipase-catalyzed resolution of racemic MPGM. This work provides a promising eco-friendly and cost-effective route toward industrial synthesis of pharmaceutically relevant diltiazem.

Molecular Catalysis published new progress about Candida parapsilosis. 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, Application In Synthesis of 5405-41-4.

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

Zhang, Zhi published the artcileAn alumina-coated UiO-66 nanocrystalline solid superacid with high acid density as a catalyst for ethyl levulinate synthesis, Formula: C7H12O3, the main research area is sulfate impregnated zirconia alumina catalyst preparation property; glucose dehydration ethyl levulinate.

The zirconium-containing metal-organic framework (MOF) UiO-66 was used as a cell to synthesize SO42-/ZrO2@Al2O3, a high-d. superacid with relatively strong Bronsted acidity. The UiO-66 MOF was first coated with alumina to form ZrO2@Al2O3. Impregnation with ammonium sulfate and calcination at 500°C afforded the bimetallic composite solid superacid SO42-/ZrO2@Al2O3. RESULTS : Scanning and transmission electron microscopy images confirmed that UiO-66 was successfully coated with aluminum oxide, and its octahedral structure and uniform size (400-600 nm) were retained. SO42-/ZrO2@Al2O3 had a Brunauer-Emmett-Teller sp. surface area of 301-330 m2 g-1 and average pore diameter of 9.6-10.7 nm. XPS and Fourier transform IR anal. showed that SO42-/ZrO2@Al2O3 contained S6+ and Al3+. Temperature-programmed ammonia desorption anal. showed that SO42-/ZrO2@Al2O3 contained super-strong acid sites. The total volume of desorbed ammonia reached 90-109 cm3 g-1. IR spectra of adsorbed pyridine indicated that SO42-/ZrO2@Al2O3 contained mainly Lewis acid sites and was relatively rich in Bronsted acid sites. Thermogravimetric anal. showed that the thermal stability of SO42-/ZrO2@Al2O3 was high. SO42-/ZrO2@Al2O3-3M (the impregnation concentration of ammonium sulfate was 3 mol L-1) and glucose were used to synthesize Et levulinate (EL) in ethanol. The highest EL yield of 37.5 mol% was obtained after reacting the mixture at 200°C for 5 h. An EL yield of 28.8 mol% was obtained after four consecutive reuses of the SO42-/ZrO2@Al2O3-3M catalyst.

Journal of Chemical Technology and Biotechnology published new progress about Dehydration catalysts. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Formula: C7H12O3.

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

Osminski, Wynter E. G. published the artcileProbing Catalyst Function – Electronic Modulation of Chiral Polyborate Anionic Catalysts, Formula: C4H8O3, the main research area is aziridine synthesis aziridiation electronic modulation chiral polyborate catalyst.

Boroxinate complexes of VAPOL and VANOL are a chiral anionic platform that can serve as a versatile staging arena for asym. catalysis. The structural underpinning of the platform is a chiral polyborate core that covalently links together alcs. (or phenols) and vaulted biaryl ligands. The polyborate platform is assembled in situ by the substrate of the reaction, and thus a multiplex of chiral catalysts can be rapidly assembled from various alcs. (or phenols) and bis-phenol ligands for screening of catalyst activity. In the present study, variations in the steric and electronic properties of the phenol/alc. component of the boroxinate catalyst are probed to reveal their effects on the asym. induction in the catalytic asym. aziridination reaction. A Hammett study is consistent with a mechanism in which the two substrates are hydrogen-bonded to the boroxinate core in the enantiogenic step. The results of the Hammett study are supported by a computational study in which it is found that the H-O distance of the protonated imine hydrogen bonded to the anionic boroxinate core decreases with an increase in the electron releasing ability of the phenol unit incorporated into the boroxinate. The results are not consistent with a mechanism in which the boroxinate catalyst functions as a Lewis acid and activates the imine by a Lewis acid/Lewis base interaction.

Journal of Organic Chemistry published new progress about Alcohols Role: RCT (Reactant), RACT (Reactant or Reagent). 623-50-7 belongs to class esters-buliding-blocks, name is Ethyl 2-hydroxyacetate, and the molecular formula is C4H8O3, Formula: C4H8O3.

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

Liu, Aiyao published the artcileSelectfluor-promoted twofold sulfination of alcohols for synthesis of sulfinic ester from diaryldisulfides, Name: Ethyl 2-hydroxyacetate, the main research area is diaryl disulfide alc Selectfluor oxidative sulfination; alkyl arylsulfinate preparation.

An oxidative two-fold sulfination of alc. with Selectfluor as an efficient oxidant was developed. This reaction proceeded smoothly achieving the unprecedented sulfination transformation of varieties of diaryldisulfides and alcs. under simple conditions, affording the corresponding sulfinic esters in excellent yields. The current reaction provided a new and convenient strategy for the preparation of sulfinic esters.

Youji Huaxue published new progress about Alcohols Role: RCT (Reactant), RACT (Reactant or Reagent). 623-50-7 belongs to class esters-buliding-blocks, name is Ethyl 2-hydroxyacetate, and the molecular formula is C4H8O3, Name: Ethyl 2-hydroxyacetate.

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

Song, Jinliang published the artcileHighly efficient Meerwein-Ponndorf-Verley reductions over a robust zirconium-organoboronic acid hybrid, SDS of cas: 539-88-8, the main research area is robust zirconium organoboronic acid hybrid catalyst preparation; alc preparation; aldehyde Meerwein Ponndorf Verley reduction zirconium organoboronic acid catalyst; ketone Meerwein Ponndorf Verley reduction zirconium organoboronic acid catalyst.

The Meerwein-Ponndorf-Verley (MPV) reaction is an attractive approach to selectively reduce carbonyl groups and the design of advanced catalysts is the key for these kinds of interesting reactions. Herein, a fabricated a novel zirconium organoborate using 1,4-benzenediboronic acid (BDB) as the precursor for MPV reduction The prepared Zr-BDB had excellent catalytic performance for the MPV reduction of various biomass-derived carbonyl compounds, such as levulinate esters, aldehydes and ketones R1C(O)R2 [R1 = Ph, furan-2-yl, Me, etc.; R2 = H, hexyl, Bn, etc.]. More importantly, the number of borate groups on the ligands significantly affected the catalytic activity of the Zr-organic ligand hybrids, owing to the activation role of borate groups on hydroxyl groups in the hydrogen source. Detailed investigations revealed that the excellent performance of Zr-BDB was contributed by the synergetic effect of Zr4+ and borate. Notably, this was the first work to enhance the activity of Zr-based catalysts in MPV reactions using borate groups.

Green Chemistry published new progress about Aldehydes Role: RCT (Reactant), RACT (Reactant or Reagent). 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, SDS of cas: 539-88-8.

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

Zhang, Haiyan published the artcileCobalt-catalyzed diastereo- and enantioselective allyl addition to aldehydes and α-ketoesters through allylic C-H functionalization, Recommanded Product: Ethyl 4-oxopentanoate, the main research area is homoallylic alc preparation diastereo enantioselective; aldehyde ketoester allylbenzene cobalt catalyst allyl addition.

Development of catalytic generation of allyl-metal complexes through allylic C-H cleavage of alkenes without prefunctionalization followed by site- and stereoselective carbon-carbon bond formation is of great importance in organic synthesis, providing a straightforward and step-economical approach to introduce a versatile allyl group into organic mols. Although significant advances have been achieved in enantioselective transformations of electrophilic allyl-metal complexes and allyl radicals, enantioselective reactions of nucleophilic allyl-metal intermediates furnished through allylic C-H cleavage remain undeveloped. Herein, authors identify a multi-tasking chiral catalyst derived from a com. available phosphine ligand and cobalt salt that precisely controls the chemoselective formation of the allyl-cobalt complex and the site- and stereoselective addition to carbonyls, delivering a broad scope of homoallylic alcs. with high yield and stereoselectivity. This work may establish a platform for the development of enantioselective transformations of nucleophilic organometallic complexes generated from catalytic C-H functionalization.

Cell Reports Physical Science published new progress about Aldehydes Role: RCT (Reactant), RACT (Reactant or Reagent). 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Recommanded Product: Ethyl 4-oxopentanoate.

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

Lv, Wen-Rui published the artcileSynthesis, Structure, and Catalytic Hydrogenation Activity of [NO]-Chelate Half-Sandwich Iridium Complexes with Schiff Base Ligands, Safety of Ethyl 3-hydroxybutanoate, the main research area is enaminoketonate sandwich iridium Schiff base complex preparation hydrogenation catalyst; iridium Schiff base complex catalyst hydrogenation ketone aldehyde nitro; crystal structure half sandwich iridium enaminoketonate Schiff base complex; mol structure half sandwich iridium enaminoketonate Schiff base complex.

N,O-coordinate Ir(III) complexes with a half-sandwich motif bearing Schiff base ligands for catalytic hydrogenation of nitro and carbonyl substrates were synthesized. All Ir complexes showed efficient catalytic activity for the hydrogenation of ketones, aldehydes, and nitro-containing compounds using clean H2 as reducing reagent. The Ir catalyst displayed the highest TON values of 960 and 950 in the hydrogenation of carbonyl and nitro substrates, resp. Various types of substrates with different substituted groups afforded corresponding products in excellent yields. All N,O-coordinate Ir(III) complexes 1-4 were well characterized by IR, NMR, HRMS, and elemental anal. The mol. structure of complex 1 was further characterized by single-crystal x-ray determination

Inorganic Chemistry published new progress about Aldehydes Role: RCT (Reactant), RACT (Reactant or Reagent). 5405-41-4 belongs to class esters-buliding-blocks, name is Ethyl 3-hydroxybutanoate, and the molecular formula is C6H12O3, Safety of Ethyl 3-hydroxybutanoate.

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

Doherty, S. published the artcileHighly efficient and selective aqueous phase hydrogenation of aryl ketones, aldehydes, furfural and levulinic acid and its ethyl ester catalyzed by phosphine oxide-decorated polymer immobilized ionic liquid-stabilized ruthenium nanoparticles, Formula: C7H12O3, the main research area is hydrogenation aromatic ketone aldehyde polymer immobilized ruthenium nanocatalyst.

Impregnation of phosphine-decorated styrene-based polymer immobilized ionic liquid (PPh2-PIIL) with ruthenium(III) trichloride resulted in facile reduction of the ruthenium to afford Ru(II)-impregnated phosphine oxide-decorated PIIL (O=PPh2PIIL). The derived phosphine oxide-decorated polymer immobilized ionic liquid-stabilized RuNPs (RuNP@OPPh2-PIILS) catalyze the highly efficient and selective aqueous phase reduction of the carbonyl group in aryl and heteroaryl ketones and aldehydes, including furfural, as well as the hydrogenation of levulinic acid and its Et ester to afford γ-valerolactone (GVL). While this is the first report of RuNPs stabilized by a phosphine oxide-modified support, there appear to be several recent examples of similar serendipitous oxidations during the synthesis of RuNPs by impregnation of a phosphine-decorated polymer with ruthenium trichloride; as these were either misinterpreted or not recognized as such we have carried out a detailed characterization and evaluation of this system. Reassuringly, RuNP@OPPh2-PIILS generated from phosphine oxide-decorated polymer immobilized ionic liquid (OPPh2-PIIL) impregnated with ruthenium trichloride is as efficient as that prepared directly from RuCl3 and PPh2-PIIL. Incorporation of PEG into the polymer support improved catalyst performance and the initial TOF of 2350 h-1 obtained for the aqueous phase hydrogenation of acetophenone is among the highest to be reported for a ruthenium nanoparticle-based catalyst. Under optimum conditions, RuNP@OPPh2-PEGPIILS recycled ten times with only a minor reduction in activity and no detectable change in selectivity. High yields and excellent selectivities were also obtained for hydrogenation of the CO across a range of substituted aryl and heteroaryl ketones. Complete hydrogenation of the aromatic ring and CO could also be achieved by increasing the pressure and temperature accordingly. The same system also catalyzes the aqueous phase hydrogenation of furfural under mild conditions with an initial TOF of 3160 h-1 as well as the selective hydrogenation of levulinic acid and its Et ester to γ-valerolactone (GVL); reaction times for the latter could be reduced quite significantly by addition of either butyric acid or Amberlyst H-15.

Catalysis Science & Technology published new progress about Aldehydes Role: RCT (Reactant), RACT (Reactant or Reagent). 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Formula: C7H12O3.

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