Esters-buliding-blocks

Du, Xu published the artcileOxidative Catalytic Fractionation and Depolymerization of Lignin in a One-Pot Single-Catalyst System, Safety of Dimethyl itaconate, the publication is ACS Sustainable Chemistry & Engineering (2021), 9(23), 7719-7727, database is CAplus.

It has been known that the yield of lignin monomers during lignin depolymerization is limited by the irreversible condensations of lignin in the fractionation and/or depolymerization process. In this study, we report a new oxidative catalytic fractionation (OCF) process with a simple and effective one-pot but two-step approach to depolymerize lignin to lignin-derived chems. (LDCs) using polyoxometalate (POM) as the only catalyst. First, the POM effectively catalyzed the methoxylation of the active α-OH groups of lignin in a methanol and water mixture at low temperature (100°C), and 96% of the stabilized lignin in the lignocellulose sawdust was extracted to the solution simultaneously. Then the lignin solution was heated to an elevated temperature (140°C) in the same solvent. As a result, 74.0 weight % of the lignin (based on the weight of the Klason lignin in the wood) was converted to LDCs, including 45.9 weight % aromatic monomers.

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, Safety of Dimethyl itaconate.

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

Sisti, Laura published the artcileChain extender effect of 3-(4-hydroxyphenyl)propionic acid/layered double hydroxide in biopolyesters containing the succinate moiety, Synthetic Route of 627-93-0, the publication is New Journal of Chemistry (2020), 44(24), 10127-10136, database is CAplus.

The 3-(4-hydroxyphenyl)propionic acid intercalated in Mg2Al/layered double hydroxide has been used as a filler in biopolyesters containing the succinate moiety, such as poly(propylene succinate) (PPS), poly(butylene succinate-co-butylene adipate) (PBSA) and poly(butylene succinate) (PBS), with the aim of inducing an effect similar to that of an increment of the mol. weight of the matrixes. The composites (1, 5 and 10 weight% of filler) have been prepared by a simple melt blending procedure. X-ray diffraction anal. revealed the presence of intercalated structures in the composites. From melt rheol. measurements, a chain extender effect of the filler, towards PBS, PPS and to some extent PBSA, was evident and proportional to the composition, producing a reinforcing role of the filler towards the polymeric chains. Moreover, no gel-like structure was produced. Such findings can be useful in widening the processing window of biopolyesters, in order to design multifunctional materials with adapted properties.

New Journal of Chemistry 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 C25H23NO4, Synthetic Route of 627-93-0.

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

Agnol, Lucas Dall published the artcileThermoplastic polyurethane/butylene-styrene triblock copolymer blends: an alternative to tune wear behavior, Quality Control of 31570-04-4, the publication is Polymer Bulletin (Heidelberg, Germany) (2022), 79(7), 5199-5217, database is CAplus.

This work presents an interesting alternative for improving thermoplastic polyurethane’s (TPUs) tribol. properties by incorporating styrene-ethylene/butylene-styrene triblock copolymer (SEBS) via melt blending. Two TPUs with different molar masses, two compatibilizers SEBS-g-MA (C1) and SEBS-b-TPU (C2) and paraffinic oil were used in the formulated blends. The raw materials’ effect on the morphol., rheol., phys.-mech. and tribol. performance of TPU/SEBS blends was monitored. The phase morphol. achieved depended on the addition of mineral oil and compatibilizer agent type. The rheol. anal. showed a pseudo-liquid viscous behavior for all samples. However, this behavior was related to the compatibilizer type and molar mass of the TPU. No significant changes were observed between the compatibilizers C1 and C2 concerning the physicomech. properties. The fact that mineral oil is preferentially contained in the SEBS phase is the fundamental point to explain the blends phase morphol. and their rheol. and phys. behaviors. The swollen state SEBS modifies the TPU’s performance. It also allows tuning properties such as abrasion and increasing the friction coefficient, enabling promising applications for these thermoplastic elastomers blends.

Polymer Bulletin (Heidelberg, Germany) published new progress about 31570-04-4. 31570-04-4 belongs to esters-buliding-blocks, auxiliary class Mono-phosphine Ligands, name is Tris(2,4-di-tert-butylphenyl) phosphite, and the molecular formula is C42H63O3P, Quality Control of 31570-04-4.

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

Prosperini, Luca published the artcileDeterminants of COVID-19-related lethality in multiple sclerosis: a meta-regression of observational studies, Safety of Dimethyl fumarate, the publication is Journal of Neurology (2022), 269(5), 2275-2285, database is CAplus and MEDLINE.

To identify risk factors for an increased lethality of COVID-19 in patients with multiple sclerosis (MS). The author searched scientific databases to identify cohort studies with the number of deaths in patients with MS. The author fitted inverse-variance weighted meta-regressions with random-effects models to identify potential moderators (determinants) of COVID-19-related lethality (outcome). After an independent screening, 18 articles satisfied the eligibility criteria; all data were collected before anti-SARS-COV-2 vaccination was available. Out of 5,634 patients, 111 died, yielding a pooled death rate of 1.97% (95% confidence intervals 1.61-2.33). There was a substantial heterogeneity between the included studies (Q₁₇ = 66.9, p < 0.001; I² = 77.5%), but no relevant publication bias (p = 0.085). Higher lethality was observed in studies including older patients (β = 0.80, p = 0.025) and in studies with higher proportions of patients with comorbidity (β = 0.17, p = 0.046), progressive disease course (β = 0.15, p = 0.027), and current treatment with anti-CD20 agents (β = 0.18, p < 0.001). Otherwise, higher proportions of patients treated with interferon beta (β = – 0.16, p < 0.001) and teriflunomide (β = – 0.11, p = 0.035) were associated with lower lethality. These estimates did not change even in both multivariable meta-regressions including adjustment variables and leave-one-out sensitivity analyses. Except for age and comorbidities, risk factors in common with the general population, the author identified MS-specific determinants influencing the lethality of COVID-19. Our findings suggest the implementation of a risk mitigation plan for patients with progressive MS and for those treated with anti-CD20 agents.

Journal of Neurology published new progress about 624-49-7. 624-49-7 belongs to esters-buliding-blocks, auxiliary class Inhibitor,Natural product, name is Dimethyl fumarate, and the molecular formula is C6H8O4, Safety of Dimethyl fumarate.

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

Kuwabe, Shin-itsu published the artcilePalladium-Catalyzed Intramolecular C-O Bond Formation, HPLC of Formula: 115314-17-5, the publication is Journal of the American Chemical Society (2001), 123(49), 12202-12206, database is CAplus and MEDLINE.

A number of oxygen heterocycles were synthesized using the palladium-catalyzed intramol. etherification of aryl halides by employing di-tert-butylphosphinobiaryl ligands. The reaction proceeds under mild conditions using weak bases such as Cs₂CO₃ or K₃PO₄. A variety of functional groups are tolerated in the reaction, and enantioenriched alcs. can be coupled without erosion of optical purity. The mildness of the reaction conditions allows for the use of polyfunctionalized substrates. This method was used as the key step in the synthesis of MKC-242, an antidepressant currently in clin. trials. The synthesis of MKC-242 was achieved in 40% overall yield from com. available sesamol and acrylonitrile.

Journal of the American Chemical Society published new progress about 115314-17-5. 115314-17-5 belongs to esters-buliding-blocks, auxiliary class Epoxides,Chiral,Nitro Compound,Sulfonate,Benzene, name is (R)-Oxiran-2-ylmethyl 3-nitrobenzenesulfonate, and the molecular formula is C9H9NO6S, HPLC of Formula: 115314-17-5.

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

Vielhaber, Thomas published the artcileManganese-catalyzed homogeneous hydrogenation of ketones and conjugate reduction of α,β-unsaturated carboxylic acid derivatives: A chemoselective, robust, and phosphine-free in situ-protocol, Synthetic Route of 103-26-4, the publication is Applied Catalysis, A: General (2021), 118280, database is CAplus.

A user-friendly and glove-box-free catalytic protocol for the manganese-catalyzed hydrogenation of ketones RC(O)R¹ (R = Ph, 2-chlorophenyl, pyridin-3-yl, etc.; R¹ = Me, Et, Ph, etc.; RR¹ = -(CH₂)₅-, -(CH₂)₄-), 3-methylcyclohexan-1-one, isophorone and 1-indanone and conjugated C=C-bonds of esters and nitriles R²C(R³)=C(R⁴)R⁵ (R² = Ph, 4-bromophenyl, 3-cyanophenyl, etc.; R³ = H, Ph; R⁴ = methoxycarbonyl, (prop-2-en-1-yloxy)carbonyl, Ph, etc.; R⁵ = H, ethoxycarbonyl, CN) was communicated. The resp. catalyst is readily assembled in situ from the privileged [Mn(CO)₅Br] precursor and cheap 2-picolylamine. The catalytic transformations were performed in the presence of t-BuOK whereby the corresponding hydrogenation products were obtained in good to excellent yields. The described system offers a brisk and atom-efficient access to both secondary alcs. (RCH(OH)R¹, cyclohexanol, 3,5,5-trimethylcyclohex-2-en-1-ol and 1-indanol) and saturated esters R²(R³)CHCH(R⁴)R⁵ avoiding the use of oxygen-sensitive and expensive phosphine-based ligands.

Applied Catalysis, A: General published new progress about 103-26-4. 103-26-4 belongs to esters-buliding-blocks, auxiliary class Alkenyl,Benzene,Ester,Protease,Tyrosinase,Natural product, name is Methyl 3-phenyl-2-propenoate, and the molecular formula is C6H10O3, Synthetic Route of 103-26-4.

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

Wang, Guang published the artcilePreparation of Azobenzene-Containing Amphiphilic Diblock Copolymers for Light-Responsive Micellar Aggregates, Computed Properties of 135529-02-1, the publication is Macromolecules (2004), 37(24), 8911-8917, database is CAplus.

Diblock copolymers composed of a side-chain liquid crystalline azobenzene-containing polymethacrylate and poly(tert-Bu acrylate) (PAzoMA-b-PtBA) were prepared using atom-transfer radical polymerization (ATRP). After subsequent selective hydrolysis of PtBA yielding poly(acrylic acid) (PAA), amphiphilic diblock copolymers of PAzoMA-b-PAA were obtained. Aggregation of either PAzoMA or PAA block occurs in solvents selective for one of the blocks. Adding water into dioxane solution of PAzoMA-b-PAA forms micellar aggregates due to the hydrophobic PAzoMA block. Under alternating UV and visible light illumination, reversible changes in micellar aggregates, for both core-shell micelles and vesicles, took place as a result of the reversible trans-cis photoisomerization of azobenzene mesogens in PAzoMA.

Macromolecules published new progress about 135529-02-1. 135529-02-1 belongs to esters-buliding-blocks, auxiliary class azo,Alkenyl,Benzene,Ester,Ether, name is 6-(4-((4-Methoxyphenyl)diazenyl)phenoxy)hexyl methacrylate, and the molecular formula is C8H11NO, Computed Properties of 135529-02-1.

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

Han, Dehui published the artcileCyclic Azobenzene-Containing Side-Chain Liquid Crystalline Polymers: Synthesis and Topological Effect on Mesophase Transition, Order, and Photoinduced Birefringence, Formula: C23H28N2O4, the publication is Macromolecules (Washington, DC, United States) (2010), 43(8), 3664-3671, database is CAplus.

A cyclic side-chain liquid crystalline polymer (SCLCP) bearing azobenzene mesogens, namely, poly{6-[4-(4-methoxyphenylazo)phenoxy]hexyl methacrylate} (PAzoMA), was successfully synthesized by using “click” cyclization of the linear polymer precursor with alkyne and azide end groups. Samples of cyclic-PAzoMA of various mol. weights were prepared, characterized, and studied in comparison with their linear counterparts. The results show that the topol. constraint arising from the tortuosity of the ring structure and the absence of chain ends in cyclic-SCLCPs affects profoundly the liquid crystalline (LC) phase transitions (temperature, enthalpy, and entropy) of mesogenic side groups and that this topol. effect is more prominent for smaller SCLCP rings. Moreover, the photoinduced anisotropy in films as a result of the trans-cis photoisomerization of azobenzene mesogens was investigated, and cyclic-PAzoMA was found to behave differently from linear-PAzoMA. On the one hand, the cyclic polymer exhibits a nonmonotonic rise and erasure of birefringence upon linearly and circularly polarized excitation (488 nm), resp., in contrast with the linear polymer displaying monotonic changes. On the other hand, unlike the linear polymer, the photoinduced orientation of azobenzene mesogens in cyclic-PAzoMA cannot be enhanced upon annealing in the nematic phase. All these manifestations of the topol. constraint suggest that cyclization offers a new way to change the coupling between mesogenic side groups and chain backbone of SCLCPs, and their interplay under the addnl. topol. effect may generate new behaviors that are of interest to be explored.

Macromolecules (Washington, DC, United States) published new progress about 135529-02-1. 135529-02-1 belongs to esters-buliding-blocks, auxiliary class azo,Alkenyl,Benzene,Ester,Ether, name is 6-(4-((4-Methoxyphenyl)diazenyl)phenoxy)hexyl methacrylate, and the molecular formula is C23H28N2O4, Formula: C23H28N2O4.

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

Cui, Li published the artcilePhotoactive Thermoplastic Elastomers of Azobenzene-Containing Triblock Copolymers Prepared through Atom Transfer Radical Polymerization, Computed Properties of 135529-02-1, the publication is Macromolecules (2004), 37(19), 7097-7104, database is CAplus.

Atom transfer radical polymerization (ATRP) was used to prepare a new series of ABA triblock copolymers that are photoactive thermoplastic elastomers. The samples synthesized have the same rubbery midblock of poly(Bu acrylate) (PnBA) but differ in the d.p. of the end blocks of a methacrylate-based azobenzene-containing side-chain liquid crystalline polymer (Azo-SCLCP). The coupling between elasticity, liquid crystallinity and photoactivity imparts interesting features to this type of thermoplastic elastomers. When the solution-cast film is stretched at T > T_g of the Azo-SCLCP whose microdomains act as phys. cross-links, in contrast to conventional thermoplastic elastomers (such as styrene-butadiene-styrene triblock copolymer) that lose the elasticity, liquid crystalline microdomains can support part of the elastic extension of PnBA chains and, in the same time, deform to result in a long-range orientation of azobenzene mesogens. The liquid crystal orientation is retained in the relaxed film at T < T_g, which creates a thermoplastic elastomer whose glassy microdomains contain oriented azobenzene mesogens. Moreover, the reversible trans-cis photoisomerization of the azobenzene chromophore can be used to modulate the mech. induced orientation.

Macromolecules published new progress about 135529-02-1. 135529-02-1 belongs to esters-buliding-blocks, auxiliary class azo,Alkenyl,Benzene,Ester,Ether, name is 6-(4-((4-Methoxyphenyl)diazenyl)phenoxy)hexyl methacrylate, and the molecular formula is C23H28N2O4, Computed Properties of 135529-02-1.

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

Liu, Yahui published the artcileNon-targeted identification of unknown chemical hazardous substances in infant teether toys by gas chromatography-Orbitrap high resolution mass spectrometry, Recommanded Product: Dimethyl adipate, the publication is Ecotoxicology and Environmental Safety (2021), 112676, database is CAplus and MEDLINE.

Chem. hazardous substances in teethers may migrate into infant’s body through oral exposure, resulting in a potential health risk. In recent years, researchers have performed a series of studies for detecting target chems. in teethers and other toys, but the presence of unknown chems. has not been systematically investigated yet. This paper reports the non-targeted identification of unknown chem. hazards that may have migrated from teethers to infants based on gas chromatog.-Orbitrap high resolution mass spectrometry. In view of the difficulties that may be encountered in the qual. anal. of substances, several typical cases and the corresponding reliable solutions are given from the perspective of comprehensive score and retention index, isotope-aided qual. anal., chem. ionization identification formula, and fragment ion detail comparison for distinguishing isomers. Finally, 28 substances are identified in 10 teether samples. Among them, phenol, N-methylaniline, 1,6-dioxacyclododecane-7,12-dione and cyclohexanone have higher detection rates. This study not only has valuable reference for the identification of unknown substances, but also has pos. guiding role in monitoring potential chem. hazards in toys and promoting the safety of products.

Ecotoxicology and Environmental Safety 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, Recommanded Product: Dimethyl adipate.

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